Category: hydroponic agriculture

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Consolidation occurring at the food manufacturing level has progressed rapidly for some time

The farm share for fruits and vegetables tends to be much lower and does not differ much between fresh and processed fruits and vegetables.The second major measure of food marketing costs in the U.S. is the marketing bill, which is calculated as the difference between what consumers spend for domestically produced farm foods and what farmers receive. In 2001 the farm share of the food marketing bill was 19 percent. This measure of the farm share has also been declining steadily over time, falling from 41 percent in 1950 to 31 percent in 1980 and then to 24 percent in 1990. The marketing bill takes account of food expenditures both at home and in restaurants. The proportion of the U.S. food dollar spent outside the home has been rising rapidly. In 2002, such expenditures accounted for 46 percent of the food budget compared to 37 percent in 1990 and 32 percent in 1980.While the overall U.S. food market is characterized by slow growth, eating habits are becoming more diverse. Demographic and psychographic trends, such as ethnic diversity and new attitudes about food consumption as it relates to self-identity and well-being, have contributed to a much more segmented market. Food marketers must increasingly target specific consumer segments rather than employing mass marketing strategies. More retailers are looking to their suppliers to assist them in understanding and better serving different types of consumer segments. In response, many suppliers are becoming involved in new types of marketing services, including consumer research and category management. The latter is designed to help retailers improve net profitability for a category of products through efficient assortment, pricing, promotion and shelf-space management. For suppliers the aim is to focus on identifying and servicing the evolving needs of specific accounts as a preferred supplier,nft channel rather than marketing more homogeneous products with fewer support services on a spot market basis. The U.S. retail industry is dominated by chain stores. In 2002, retail chains accounted for 83 percent of supermarket industry sales vs. 58 percent in 1954 .

The remainder of sales is by independent stores, although the vast majority of these stores are affiliated to buying groups, either voluntary chains such as Supervalu or to a lesser extent retailer cooperatives such as Associated Wholesale Grocers. In 2002 there were 32,981 supermarkets including all format types. Firms in the U.S. food-marketing sector often view a large market share, including, if possible, the position of market leader, as a key requisite to success. Pursuit of market share has led to a dramatic consolidation in the U.S. food chain at all levels, ranging from the farm through food retailing. Due to the difficulty of capturing sizable market share from rival firms, many U.S. food marketers have pursued share growth through mergers and acquisition of rivals. Mergers and acquisitions in the food sector occurred at a rapid pace in the 1980s, temporarily peaked in 1988 at 573 mergers, declined and then reached an all-time high of 813 in 1998, since declining to 415 in 2003 . Although the growth in merger activity has temporarily abated, cumulative activity in recent decades has likely had important implications for the structure of competition in the U.S. food sector.About 16,000 food and tobacco processing companies operate in the U.S., but in 1997 about 75 percent of sales were by the 100 largest of these firms. The largest sales growth, fueled mostly by mergers and acquisitions, has been recorded by the top 20 of these 100 firms, which in 1997 were estimated to account for about 50 percent of value added in food manufacturing . Most of the 53 food and tobacco industries surveyed in the U.S. Census of Manufacturing have experienced increasing concentration over time. The average market share held by the four largest firms in these industries has risen from 43.9 percent in 1967 to 53.3 percent in 1992, the most recent year for which data are available. In contrast to the food manufacturing sector, over the decade 1987-97 retail concentration ratios were quite stable with the share of U.S. food sales accounted for by the top 4, 8 and 20 retailers at about 20, 30, and 40 percent, respectively. During this decade new players were emerging in the U.S. food system, including value oriented retailers such as Wal-Mart with its fast expanding super center and club store formats, specialty food retailers like Trader Joe’s, European entrants into U.S. food retailing, and other mass and drug store merchandisers entering the food business.

This phenomenon is called channel blurring and continues with the recent emergence of “Dollar Stores,” on-line food shopping and the on-going competition from the food service sector for the consumer food dollar. This challenging marketplace motivated many conventional retailers to become larger in hopes of improving their competitiveness. From 1997-1999, in particular, mergers occurred between several already large retail chains, beginning to induce important and still unfolding changes in relationships between buyers and suppliers. By 2002 the estimated share of U.S. food sales accounted for by the top 4, 8 and 20 retailers had reached 31, 45, and 57 percent, respectively. This means that in 2002 suppliers faced a market where only 20 retail firms sold at least $276 billion in food. Despite the mergers, the United States has no truly national supermarket chains. In 2002 only eight chains had over 1,000 stores, and only one of these has over 2,000 outlets. Given the large geographic size of the United States, chains tend to be regional in focus. However, the recent high merger activity has contributed to much larger chains than ever before, with five surpassing $25 billion in sales in 2002, and four with stores in over half of the country. Still, many local and regional chains remain quite competitive by staying in close contact with their customers and implementing highly targeted marketing strategies. The regional,hydroponic nft ethnic and demographic diversity of U.S. consumers leads some to predict that small to mid-size chains may have an important role to play for some time to come. Within the retail channel the super center concept has emerged as a major industry force, which further concentrates buying power in the hands of a few very large new players. Super centers are a type of mass merchandising format combining a full-line supermarket with a full-line discount department store and range up to 24,400 square meters in size , compared to 4,900 square meters for the average supermarket. Total 2002 grocery-equivalent sales of super centers were estimated at $45.5 to $50.3 billion with total super center sales reaching $116.7 billion . The largest entrant to this format is Wal-Mart, with an estimated $29.3 billion in U.S. grocery-equivalent 2002 food sales, a 75 percent share of national super center sales and 1,333 super centers as of mid-2003. Already the largest retailer in the world, operating in ten countries, Wal-Mart is opening over 200 new super centers per year in the U.S. alone, and is fast becoming the dominant global player in grocery retailing with $244.5 billion in 2002 global sales among all its store formats, including large discount stores and warehouse club stores .

Wal-Mart has also entered the conventional grocery-retailing sector in the U.S. with 52 neighborhood markets in 2002, and growing. Wal-Mart’s immense buying power combined with its approach of driving non value-adding costs out of the food system appears to have raised the competitive benchmark for conventional retailers. It emphasizes supply chain management via covendor managed automatic inventory replenishment procurement systems. Vendors have shared responsibility for growing the category and have real-time access to data on sales of their products via Wal-Mart stores. In exchange, they provide special services, packs and support, such as category management, tailored to the needs of the Wal-Mart account. Even for volatile fresh produce items Wal-Mart tends to operate on a seasonal or annual contract basis with a small number of preferred suppliers per product or category. Other retailers are also developing closer linkages with preferred suppliers, gradually causing a shift away from the spot market, the traditional modus operandi in fresh produce procurement. Another factor contributing to greater food retailer market power is the intensifying battle for their limited shelf-space by food marketing firms. During 2003, food-marketing firms introduced 11,574 new food products . Since the average supermarket carries about 30,000 product codes, competition among firms introducing new products has led to the common practice of retailers charging fees known as “slotting allowances” for allocating shelf space to new products. Supermarket space allocations and the competition for display areas are critically important to California marketing firms. Until recently, fresh produce was exempt from slotting allowances, but these fees entered the produce department in the latter half of the 1990s with the introduction of branded fresh-cut produce. These items, like other consumer packaged goods commonly subject to slotting allowances, require dedicated shelf-space year-round. While bulk produce items are still not usually subject to slotting allowances, payment of other types of fees has increased marketing costs for growers and shippers . Increased retail buying power is influencing supplier strategies and inducing marketing alliances and joint ventures at the shipper level. Shippers have increasingly sought to come closer to matching the scale of the fewer, larger buyers. Marketing alliances between shippers appear to be the mechanism of choice as they allow each party to maintain its own growing, packing and cooling operations. This seems important for fresh produce shippers, most of which are family-owned and not publicly traded even if their businesses are structured as corporations. The larger scale obtained from marketing alliances helps firms to make greater investments in marketing systems and services, since they can be spread over a higher sales volume. Each year more suppliers are offering category management services, broadening their product lines, and becoming year-round, either via domestic or international diversification of supply sources. This greater vertical coordination can enable both suppliers and retailers to plan more effectively and reduce transaction costs, thereby improving the horizontal competitiveness of each party.U.S. food demand trends reflect the preferences of an older, wealthier, more ethnically diverse and more educated population today than 20 years ago. The entrance of more women into the workforce, in conjunction with higher incomes, has led to an increased demand for convenience in food preparation and consumption. In general, lifestyle and demographic trends have stimulated demand for eating out as well as for more value added, higher-quality, specialty and convenient food products sold in retail establishments. In response to decades of market share erosion to food service, food retailers increasingly seek to compete by providing ready-to-eat home meal replacement offerings. This implies greater retail recognition that their offerings have traditionally been “ingredients to prepare” while consumers have increasingly sought“meals to eat.” Food suppliers are actively assisting retailers in launching these more convenient new products. More and more, differentiated, specialty food products may also be organically grown, as both growers and marketers seek points of difference to compete in a saturated food marketing system. Organic foods are estimated to account for around 2 percent of U.S. retail food sales, about $9-9.5 billion in 2001 . As the nation’s largest producer of organically grown commodities California producers are major participants in the growth of this sector . Fruits and vegetables have benefited from many demographic and lifestyle trends occurring over the last 25 years, a plus for California’s horticultural-reliant agriculture. For example, higher-income households on average consume more fresh produce than do lower-income households; in 2000 households earning more than $70,000 per year on average spent $496 dollars on fresh produce annually, compared to $302 for households in the $15,000 to $29,999 range . Hispanic households, the most rapidly growing segment of the population, consume more fresh produce than do non-Hispanic Whites or African Americans . Hispanics currently represent around 13 percent of the population and are projected to reach 18 percent by 2020. However, despite the forces favoring healthful diets, U.S. consumers have become more overweight, with two-thirds of adults estimated by USDA to be overweight in 2000, including one-third obese. According to ERS’s loss-adjusted annual per capita food supply series, average daily calorie consumption was 12 percent, or roughly 300 calories, above the 1985 level .

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The co-op could also help increase demand by advertising and developing new markets

The wage differentials with traditional producing countries in the Mediterranean Basin were much larger, with California farmers paying roughly 4 to 8 times more. Moreover, most fruit and nut crops were characterized by high labor-to-land ratios. For example, the U.S. Department of Agriculture estimated that in 1939 producing almonds on the Pacific Coast required 96 hours per bearing acre, dates 275, figs 155, grapes 200, prunes 130, and walnuts 81 hours; this compared with only 6.6 hours of labor per acre of wheat.Underlying the Hechsher-Ohlin analysis is the notion that wheat farmers competed directly with fruit and nut growers for the labor and land. But this notion needs to be qualified in ways that help explain the success of California fruit producers. On the Pacific Coast, the labor requirements of both activities were highly seasonal and their peak harvest demands did not fully overlap. In California, for example, the wheat harvest was typically completed by early July whereas the raisin and wine grape harvest did not commence until September and continued through late October. Hence, a worker could, in principle, participate fully both in the grain and grape harvests. Rather than conceiving of the different crops as being competitive in labor, we might be better served by considering them as complimentary. As an example, in the lush Santa Clara Valley harvest workers would migrate from cherries to apricots to prunes to walnuts and almonds over a roughly six month season. Adding other semi-tropical crops, such as cotton and navel oranges, stretched the harvest season in large sections of California into the winter months. By filling out the work year and reducing seasonal underemployment, the cultivation of a range of crops in close proximity increased the attractiveness to labor of working in Pacific Coast agriculture. The succession of peak-load, high-wage periods allowed California workers more days of high-intensity and high-pay work in a year than was possible in most other regions.It is also important to recognize that the land used for grain and fruit crops was largely “non-competing.” Prime quality fruit lands,led grow lights with the accompanying climatic conditions, were so different from the lands that remained in grain production that they constituted a “specific input.”

Differences in the land values help bring these points home. According to R. L. Adams’ 1921 California farm manual, the market value of “good” wheat land in the state was approximately $100 per acre in the period immediately before the First World War.“Good” land for prune production was worth $350 even before planting and valued at $800 when bearing. The “best” land for prunes had a market value of $500 not planted and $1000 in bearing trees. Similarly, “good” land for raisin grape production was worth $150 raw and $300 in bearing vines; the “best” sold for $250 not planted and $400 bearing. Focusing on physical labor-to-land ratios in comparing wheat and fruit production can be seriously misleading because the acreage used for fruit cultivation was of a different quality than that used for grains.A further reason why horticultural crops could compete was that, unlike the key agricultural staples, many fruit and nut products enjoyed effective tariff protection during the late-19th and early-20th centuries. Tariffs almost surely sped up the growth of Mediterranean agriculture in the United States and were strongly supported by domestic producers, railroads, and packers.One of the recurrent justifications for tariffs offered by domestic growers was to help offset high transportation differentials. Almost across the board, Mediterranean producers enjoyed lower freight rates to the key markets of the northeastern United States than their American rivals did. For example, circa 1909, shipping currants from Greece to New York cost 17 cents per hundred weight while the freight on an equivalent quantity of California dried fruit averaged about one dollar.For the Pacific Coast fruit industry, the cost of transportation remained an important factor, shaping production and processing practices. This is reflected in an observation that has entered textbook economics, that the best apples are exported because they can bear the cost of shipping. It also helps explain one of the defining characteristics of the region’s fruit industry, its emphasis on quality. Local producers and packers devoted exceptional efforts to improving grading and quality control, removing culls, stems and dirt, reducing spoilage in shipment, and developing brand names and high quality reputations. This focus makes sense given the high transportation cost that western producers faced in reaching the markets of the U.S. Atlantic Coast and Europe. To a large extent, the ability of Californians to compete with the growers in southern Europe depended on capturing the higher end of the market.With only a few exceptions, California dried fruits earned higher prices than their European competition because the state’s growers gained a reputation for quality and consistency.

As an example, the U.S. produced far higher quality prunes than Serbia and Bosnia, the major competitors, and as a result American prunes sold for roughly twice the price of the Balkan product in European markets. Not only were California prunes larger, they also enjoyed other significant quality advantages stemming from the state’s better dehydrating, packing, and shipping methods.Similar quality advantages applied virtually across the board for California’s horticultural crops. It is interesting to note that at least some of California’s current problems with foreign competition stem directly from the ability of others to copy the state’s methods. After the California horticultural industry established its strong market presence, the message eventually got through to other producers. The extensive efforts that producers in other New Areas and in Europe made to copy the California model provides another indicator of the importance of superior technology and organization in establishing California’s comparative advantage.California agriculture was uncommonly successful with collective action. By the 1930s, the state’s farmers supported a powerful Farm Bureau, organized labor recruitment programs, numerous water cooperatives and irrigation districts,vertical grow system and a vast agricultural research establishment. Here we will focus on the state’s experience with cooperatives designated to provide farmers with an element of control over the increasingly important marketing, middleman, and input supply functions. One of the most notable was the California Fruit Growers Exchange organized in 1905. By 1910 it marketed 60 percent of the citrus shipped from California and Arizona under its Sunkist label; in 1918 it marketed 76 percent of all shipments, and for most years between 1918 and 1960 Sunkist accounted for over 70 percent of citrus shipments.The Exchange also entered the farm supply business through its subsidiary, the Fruit Growers Supply Company. In the late 1920s it was purchasing for its members $10,000,000 a year worth of nails, tissue wraps, fertilizer, orchard heaters, box labels, orchard stock and the like. The company also controlled 70,000 acres of California timber land and manufactured huge quantities of boxes.Other co-ops emerged catering to California’s specialized producers. After more than 20 years of unsuccessful experiments, raisin growers banded together in the California Associated Raisin Company in 1911. Between 1913 and 1922 the CARC handled between 87 percent and 92 percent of the California raisin crop, successfully driving up prices and members’ incomes. But success brought Federal Trade Commission investigations and an anti-trust suit, which the CARC lost in 1922. In 1923 CARC was reorganized into Sun Maid Raisin Growers of California.

Although that brand name still survives, the co-op was never again as successful as it was in its first decade. Co-ops potentially offered their members several services. First, they could help counteract the local monopoly power of railroads, elevators, packers, banks, fertilizer companies and the like by collectively bargaining for their members; or as in the case of the California Fruit Growers Exchange, the co-op could enter into the production of key inputs and offer its own warehouses, elevators, and marketing services. Several coops representing various specialized crops have developed very successful marketing campaigns that have significantly increased consumer awareness and consumption. While perhaps providing countervailing power and overcoming market imperfections on the output side, many co-ops strove to introduce their own imperfections by cartelizing the markets for agricultural goods. A leader in this movement was a dynamic lawyer, Aaron Sapiro, who had worked with several of California’s co-ops in the early twentieth century. His plan was to convince farmers to sign legally binding contracts to sell all of their output to the co-op for several years. If a high percentage of producers in fact signed and abided by such contracts, then the co-op could act as a monopolist limiting supply and increasing prices. Since the demand for agricultural products is generally thought to be highly inelastic, farm income would rise. The surpluses withheld from the market would either be destroyed or dumped onto the world market.The whole scheme depended on: avoiding federal anti-trust actions like that which hit the raisin growers between 1919 and 1922; preventing foreign producers from importing into the high priced American market; and overcoming the free rider problem. Even if these problems could be solved in the short-run, the longer-run problems of controlling supply in the face of technological change and increasing productivity in other countries would still exist. The first two problems were fairly easily dealt with. The cooperative movement received federal encouragement in the form of highly favorable tax treatment and considerable exemption from anti-trust prosecution with the passage of the Capper Volstead Act in 1922. Subsequently, the Cooperative Marketing Act of 1926 and the Agricultural Marketing Act of 1929 further assisted the cooperative movement by helping to gather market information , and by helping co-ops enforce production and marketing rules. In addition, the 1929 Act provided up to $500 million through the Federal Farm Board to loan to cooperatives so they could buy and store commodities to hold them off the market. The federal government also provided a shot in the arm to the cooperative movement through a series of tariff acts that separated the domestic and foreign markets. The tariffs were in large part endogenous because co-op leaders and California legislators lobbied furiously for protection. But overcoming the “free rider” problem was a harder nut to crack. Every farmer benefited from the co-op’s ability to cut output, and every farmer would maximize by selling more. There was thus a tremendous incentive to cheat on the cartel agreements or to not sign up in the first place. The early California fruit co-ops were successful in large part because they dealt with crops grown in a fairly small geo-climatic zone for which California was the major producer. Many growers were already members of cooperative irrigation districts and thus linked by a common bond. These factors made it much easier to organize and police the growers, and it reduced the chance that higher prices would immediately lead to new entrants who would, in a short time, drive the price level down. The fact that most output was exported out of the state via relatively few rail lines also made monitoring easier. If California raisin prices increased, it was not likely that Minnesota farmers would enter the grape market; but if Kansas wheat farmers banded together to limit their output, farmers in a dozen states would gladly pick up the slack. For these reasons the success of cooperatives in California was seldom matched elsewhere in the United States.California agriculture defies simple, accurate generalizations. This chapter gives the reader two of many possible cross-sectional views of the state’s agriculture to portray the diversity and complexity which make simple descriptions impossible. California’s agriculture has always been sufficiently different from farming and other related activities found elsewhere in the United States, or in the world for that matter, to befuddle visitors and the uninformed. When discussing farming with visitors from the other 49 states, and places even more afield, my father, a life-long Yolo County farmer, always proudly stated, “Anything that can grow anywhere, can grow somewhere in California!” He was right, of course. The state’s agriculture, founded on self-sufficiency goals of early Alta California missions, developed in less than two centuries from a predominantly livestock grazing economy, providing wealth to large, Rancho land holdings from the sale of hide and tallow products in the early 1800s, to today’s agriculture which includes highly capitalized, intensively managed firms as well as a large number of “small” and part-time farming operations.

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Collected specimens that were damaged were identified to the closest identifiable morphospecies

Existing literature on the effects of urbanization on species occurrence, abundance, and diversity often relies on urban-rural gradient studies . These studies generally find that increased urbanization decreases the diversity of organisms . Confirming these findings are an abundance of patch-matrix literature suggesting that the quality of the habitat patch itself, its size, and the composition of the matrix surrounding it are determining factors for species occurrence in fragmented landscapes . Specific to UA, higher imperviousness surrounding urban farms has been related to decreased parasitoid abundance and richness , decreased predator abundance and richness , and even decreased predation on sentinel prey . To better understand PH richness and abundance in urban farms and associated biological control services, we conducted an in-situ survey at urban community farms in the East Bay of the San Francisco Bay Area, USA. Eleven farms participated in 2018 and ten farms in 2019. Farms were asked to participate in research based on two factors: 1. farm size, to ensure a comparative sample of small, medium, and large farms, and 2. high or low levels of surrounding impervious surface per the National Landscape Cover Database . Landscape factors and APM practices of farms were measured. APM practices included area of non-crop usage , area of production, crop plant abundance , crop richness, floral richness,plastic plant pot sizes and percent of farm surface with complex ground covers including mulch and leaf litter. Landscape factors included percent of impervious surface at 200-, 500-, and 1000-meter radii. Sampling iterations occurred from May to mid-October each year. On-farm non-crop area was defined as a not actively managed area of the farm occupied by non-crop flora. Farm size in m2 was calculated through Google Earth Pro and ground-proofed during on-farm spatial measurements. Brassica abundance was determined by counting all brassicas on the farm when sampling occurred.

Crop plant richness was determined by eight meter transects measured perpendicular to garden beds three times during the growing season. Different cultivars of the same species were counted separately when measuring crop richness. Floral richness was surveyed three times per growing season by completing a comprehensive count of each flowering plant at each survey site. Randomized 4m2 quadrats were used to estimate percent of and type of cover . Ground cover quadrats were measured across crop and non-crop areas. Percent of surrounding impervious surface for each farm was measured using the NLCD at 8m resolution .Collection of PH was accomplished by using an insect vacuum on Brassica oleracea cultivars, including broccoli, kale, collards, and tree collards. Each sampled plant was randomly selected and was only sampled if it was standing free of other herbaceous cover and flowering plants. A total of nine plants of each cultivar present were sampled per visit. Vacuum sampling occurred monthly from May to October. Vacuuming of each plant lasted for five seconds. For this work, we assume that sampled wasps were performing foraging or host-seeking behaviors on selected plants . Each sample was frozen until processed by extracting all PH and identifying them to the lowest taxonomic level possible per previous literature . PH identification was accomplished using Hymenoptera of the World . Chalcidoidea were identified with the Annotated keys to the Genera of Nearctic Chalcidoidea , and Braconidae using the Manual of the New World Genera of the Family Braconidae .Cabbage aphids, Brevicoryne brassicae were visually identified and abundance was assessed by doing a total count on three random leaves on nine brassicas per cultivar, including counts of apterous, alate, and parasitized aphids. Aphid abundance counts were performed monthly from May to October on non-vacuum sampling days to reduce PH disturbance. Parasitism rates were calculated as number of parasitized aphids divided by number of total aphids on each leaf.

Generalized linear mixed models were constructed using the MASS R package to explore whether APM practices or landscape factors affected PH abundance on common brassicas. Each response variable: All PH, PH super family, family, and subfamily abundance, overall site PH diversity, and rates of aphid parasitism were modeled with both local and landscape factors. Local factors include the percent of mulch ground cover, floral and crop richness, production, and non-crop area. Landscape factors include percent impervious surface at 200, 500, and 1000m radii, and farm size. Seasonal factors included both year and season and were assessed as categorical variables: early-season , mid-season , and late-season . The fitdistrplus package in R was used to find appropriate distributions for modeling . A negative binomial or Poisson distribution with a log link function was selected as appropriate given the zeroinflation of the count data. Models were fitted with the glmer.nb or glmer function in R package MASS . Preliminary models with all measured local and landscape factors were constructed for each response variable. Explanatory variables of low importance for all response variables were excluded from subsequent models. Final models were assessed for fit using the Akaike Information Criterion and diagnosed for over or under-dispersion by comparing observed residuals with expected residuals using the DHARMa package in R. Poorly fitted models were excluded from the results . Partial regression plots for final models were developed using the “effects” package in R and are reported in Results . The slope of the line in these plots represents the association between a single explanatory variable and a response variable accounting for the effects of each other variable within the fitted model.To test the local and landscape effects on the enemies hypothesis vis-a-vis APM on populations of PH in urban agroecosystems, we collected data from twelve urban farms in the San Francisco Bay Area over a period of two growing seasons. Participating farms were selected to represent a continuum of size, spatial composition, and surrounding imperviousness.

Non-crop area was a significant predictor for all PH, cynipoid, and braconid wasps. Effects of APM practices were varied, but increased crop richness and mulch coverage were associated with increased abundance of all Chalcidoidea, including the Aphelinidae. Increases in crop richness also showed an increase in parasitism rates of aphids on brassica crop plants. Unexpectedly, Floral richness showed a negative relationship to the abundance of all PH, as well as chalcids, and all Braconidae. All PH showed a significant decline in abundance during the late season of 2019. All measures of impervious surface surrounding urban farms had no effect on PH abundance or aphid parasitism on the urban farms. Landscape effects to arthropod mediated ES continue to have mixed results and this research supports previous findings in urban agriculture which show both negative and positive effects to natural enemy abundance and diversity . Non-crop areas identified in this research are difficult to identify explicitly as either managed or unmanaged and existed on a spectrum that was often difficult to quantify in interviews or through survey work. However, these areas most frequently had been improved with flowering perennials or annuals, medicinal or “native” flora, and farmers typically stated the purpose as providing a resource for wildlife or beneficial insects. Previous research supports farmer efforts. Structural diversity has been found to elicit positive responses with regard to diversity and abundance of predators and PH in previous UA studies . These areas may provide critical over-wintering habitat in annual cropping systems,blueberry plant container additional hosts or prey, shelter, floral nectar resources for nectarivorous insects . Our findings suggest that these non-crop areas have the potential to influence agroecosystem function in UA, and may be an important part of APM practices, even in highly fragmented landscapes. Moreover, floral richness had little effect on PH abundance, or parasitism of aphids, signaling that increase in PH abundance were not due to floral nectar within these non-crop areas. Another mechanism that may be of importance are the spatial composition of the agroecosystem. Our research did not take into account the overall distribution of non-crop area within the farm, which may have failed to account for spatial heterogeneity that has been found to illicit positive and negative biological control responses in agroecosystems . Future research on urban farms should account not only for the proportion of non-crop areas, but also spatial heterogeneity to further explore these effects. Overall, APM practices, such as increased mulch coverage and crop plant richness were important predictors of PH abundance, and increased aphid parasitism rates. The connection between mulch, complex ground covers, and increased abundance and diversity of parasitic wasps has been previously observed in urban agroecosystems , a variety of natural habitats, and rural agroecosystems . It is unlikely that mulch would provide a direct resource for PH, but PH may benefit from mulch as a potential overwintering habitat or it may provide habitat for potential hosts. Many of the collected PH were parasitoids of dipteran larvae; these larvae are herbivorous but complete part of their life cycle in soils. I suggest that the overall biodiversity of urban farms with increased mulch coverage may create a bottom-up trophic cascade that increases overall soil arthropod diversity benefiting PH populations. Floral richness had a negative effect on PH abundance in all models. Floral richness was chosen as an explanatory variable as it has previously been found to increase PH abundance in UA . The vast majority of PH are nectarivorous, and this additional nectar resource has been suggested frequently as a strategy for increasing populations, potentially leading to increased parasitism . However, conflicting data raises questions about this on farm manipulation and whether PH seek hosts in the same area they feed, or they disperse to increase fecundity . A large proportion of our overall sample of PH were cynipoids, potentially from the genus Alloxysta, known hyperparasitoids of both dominant primary aphid parasitoids in our sample, Aphidiinae, and Aphelinidae . These reductions in primary aphid parasitoid populations may be due to direct or indirect negative effects from this hyperparasitoid that also feeds on floral nectar . In urban agroecosystems, floral provisioning as a habitat manipulation may be complicated by the inherent fragmentation and quality of the urban matrix.

For floral resources to be an effective APM practice, this resource must be limited. Potential concentrations of alternate off-farm floral resources may complicate this affect. While this research expanded upon previous findings and can be of utility for urban agroecosystem management, many questions remain. Firstly, the effects of hyperparasitism on biological control in UA. Our third most collected taxon was Cynipoidea, many of which are often hyperparasitoids of aphid parasitizing wasps . Given that these cynipoids were collected from plant foliage in close proximity to many primary aphid parasitoids, there is some anecdotal evidence that these cynipoids were engaging in host-seeking behavior. If some of the measured on-farm management practices, such as increased non-crop areas also increase abundance of Cynipoidea, this could result in decreased biological control services. In this case, floral provisioning may potentially be acting as an ecosystem disservice . Unfortunately, we were unable to collect parasitized aphids and rear any hyperparasitoids during this research, but these findings suggest that hyperparasitism in fragmented UA landscapes may be a mechanism affecting APM strategies in UA. Crop plant richness positively affected the abundance of all Chalcidoidea and the subfamily Aphelinidae. Crop richness was also a predictor of greater parasitism rates of cabbage aphids on sampled brassica. Similar findings in rural and urban agroecosystems, including increased PH abundance and biological control services in relation to increased crop diversity have been previously documented . Given that intercropping is commonly practiced in UA, these results validate the efficacy of the practice, and offer an opportunity to investigate the extent of the effect in future research efforts. 4.3 Seasonal factors Seasonal effects on PH abundance were mixed, but many affects were measured in the second year of our sampling. Of note, in 2019, we had fewer sampling events as one farm was unable to participate in our study, but more PH were collected in that year despite the smaller sampling pool. Rates of aphid parasitism were significantly decreased between mid- and late season in 2019. It is unknown what drove these effects, but notable that such a significant difference could occur between sampling seasons. Future research efforts should consider seasonal differences and weather when drawing conclusions about on-farm or landscape factors to PH abundance or diversity or associated biological control services.

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Do Plants Grow Faster Hydroponically Or In Soil

Plants can grow faster hydroponically under certain conditions compared to traditional soil-based cultivation. Hydroponics is a method of growing plants without soil, using a nutrient-rich water solution as the growing medium. There are several reasons why plants can grow faster in growing hydroponically:

  1. Nutrient availability: In hydroponics, plants receive a balanced nutrient solution directly, allowing them to access essential nutrients in optimal concentrations. This eliminates the need for plants to expend energy searching for nutrients in the soil. Consequently, plants can allocate more energy towards growth and development.
  2. Water and oxygen availability: Hydroponic systems provide a constant supply of water and oxygen to the plant roots. This ensures that the roots receive an ample amount of both elements, promoting efficient nutrient uptake and faster growth.
  3. Reduced disease and pest pressure: By eliminating soil, hydroponic systems can reduce the risk of soil-borne diseases and pests that can hamper plant growth. The controlled environment of hydroponics also allows for better disease and pest management.
  4. Increased control over growing conditions: Hydroponics allows growers to have precise control over environmental factors such as light, temperature, humidity, and pH levels. Optimizing these conditions to suit plant growth requirements can result in faster growth rates.

However, it’s important to note that the actual growth rate can vary depending on the specific plant species,blackberry cultivation the hydroponic system used, and the level of expertise of the grower. Some plants may exhibit better growth in soil-based systems due to their specific nutrient requirements or adaptation to soil environments. Ultimately, the choice between hydroponics and soil-based cultivation depends on the specific goals, resources, and expertise of the grower.

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Costs added along the marketing chain to the final consumer often add as much or more than farm costs

That means crops Flexibility and resourcefulness by California farmers have minimized drought-induced supply reductions for tree, vine and vegetable crops, for which California has large market shares and for which retail prices would be sensitive to California disruptions. Water is being shifted away from field crops that enter the food supply indirectly and for which California is not a dominant producer. These facts mean that even a severe drought is having only slight impacts on supplies to consumers and thus only slight impacts on consumer food prices. Of course, the longer the drought lasts, the larger the impacts. grown in the Central Valley have been more subject to government mandated water cuts than crops grown in regions with a higher reliance on groundwater or local deliveries. Crops such as fresh vegetables, berries, avocados, and high-priced wine grapes are grown mostly in regions that have faced fewer mandated cuts in water supplies. Crops such as tree nuts and tree fruit, lower-priced wine grapes, and field crops tend to be grown in the Central Valley where they have been subject to more surface water cutbacks . Second, when droughts occur, farmers have strong incentives to shift water to crops with higher net revenue per acre-foot of water in order to minimize economic losses. Forage crops such as hay, corn silage, irrigated pasture, grain crops, and other field crops have much lower revenue per acre and require more acre-feet of water than tree and vine crops or vegetables . During a drought year, multi-crop farms have strong incentives to reallocate their water to crops that generate more potential profit or at least minimize losses—including losses of capital invested in orchards and vineyards. A farm growing say, grapes and wheat, will naturally leave the wheat field unirrigated to save water and keep vines alive and productive. And, farms that have the physical and legal ability to shift water to others, hydroponic grow systems will naturally be more willing to transfer water away from low revenue per acre field crops and toward other farms, either nearby or, often, much further south, that use water for tree nuts, fruits, or vegetables.

Geography and irrigation infrastructure reinforces the tendency for concentrating supply reductions on field crops. The primary regions for growing fresh vegetables and berries in California include the central and southern coastal valleys and Imperial County. Imperial County receives irrigation water from the All American Canal and the Colorado River system, thus insulating the region from this California drought. The coastal valleys have had low precipitation but rely primarily on local groundwater aquifers that have not been under as much pressure during this drought as those in the Central Valley. Table 1 lists lettuce as the representative fresh vegetable crop, but the Central Coast is also home to most production of crops such as celery, broccoli, and spinach. The Central Coast, from Santa Cruz County down the coast to Ventura County, also produces most of the strawberries and raspberries. The high revenue per acre and per acre-foot of water for crops such as strawberries and lettuce also provide great incentives to apply the irrigation water needed to sustain production. Irrigation water per acre varies widely by crop and region, from around one acre-foot per acre for winter and spring vegetables grown in cool coastal regions with ample humidity, up to perhaps five acre-feet per acre for some trees and alfalfa in the hot and dry southern San Joaquin Valley. Of course, crop yields are also high where irrigation use is high. Water costs per acre-foot also vary widely from lows of $20 to $50 per acre-foot for surface water in the north, in places where water has been plentiful or where groundwater tables are near the surface. Regular pumping costs or delivery costs can exceed $1,000 per acre-foot in some regions and during drought periods. In general, however, it is clear that where physically feasible and allowed by regulation, farms will tend to use available water on tree, vine, and a few other crops while shifting water away from field crops. The drought affects California production of livestock commodities mainly through impacts on forage crop output. Poultry, egg, dairy, and finished beef production relies mostly on grains shipped in from other states. But, California-produced hay, silage, and irrigated pasture are important for cattle. Hay and silage, mostly produced in California, comprise about 20% of California milk production costs.

Therefore, a 50% increase in costs of hay and silage due to the drought would increase milk production costs at the farm by a bit less than 10%. Many observers point to the large share of California produce in the nation’s supply. Table 2 indicates California’s large share of U.S. production for tree, vine, and vegetable crops. These are the crops for which the current drought is not causing large supply cuts. California has smaller market shares for livestock and field crops where California supply reductions are large. These facts mean that even when California supply falls significantly, say for wheat, rice or hay, the amount in the U.S. or relevant global market falls by a much smaller percentage. Two caveats affect the interpretation of these production shares. First, for some important crops, the relevant markets are global. For example, Table 2 indicates that about two thirds of California almonds and about half of California rice are exported. Global market share is crucial. For almonds, California also has a large share of the global market so if supply were to fall , price would indeed rise. Exports are also important for dairy products, processing tomatoes, and rice. Markets for each of these commodities faces particular conditions. In the case of milk and tomatoes, California ships processed products into competitive national and global markets. For rice, California is a tiny part of global markets, but produces a specialized style of rice for which California production shortfalls do affect price somewhat. Finally, in the case of wine, imports matter as well as exports. While California dominates U.S. wine production, the market is quite competitive— especially in the case of wine from Central Valley grapes that are most likely to be affected by drought.Of course, farm price changes are not the only driver of retail prices.For example, the farm share of retail cost for strawberries or lettuce is 30% but only about 7% for bread. These relationships mean that even if prices rise at the farm, the percentage impact for retail consumers is generally muted—and more muted for processed products and those subject to costly and specialized marketing and transport. Flexibility by retailers and consumers also moderates price impacts.

Given that drought has slowly evolving impacts with substantial warning, wholesale and retail buyers have ample time to plan ahead and source products from where they are most available. Finally, many consumers are willing to substitute across products such as types of melons or lettuce, or from table grapes to some other fruit if relative prices change. California produces about 20% of the U.S. milk supply,hydroponic channel which can be processed into cheese. The farm share of the retail price for cheese is about 30%. That is, the price of milk before it has been processed into cheese makes up 30% of the cheese retail price. The own-price elasticity of demand for milk, a measure of the responsiveness of quantity demanded to a given change in price, is -0.3. Given the reduced hay and forage supplies to the dairy industry and associated higher prices, we estimate that California milk production may decrease by 5% due to the drought. Plugging these parameters into the equation tells us that the retail price of cheese would increase by 1%. California is the dominant supplier of fresh produce in the U.S. during much of the year, and its share of the U.S. lettuce market is about 80%. Given a 3% decrease in the quantity of lettuce supplied by California farms, retail price would increase by about 1.5%. California produces japonica rice for the U.S. and international markets. California rice accounts for about half of the relevant U.S. market, some of which uses specialized California rice and some of which uses medium grain rice produced elsewhere. The market share and demand elasticity reflect that California rice is unique for certain uses in some markets and has close substitutes for other uses. Because of severe reductions in surface water availability, California quantity of rice will likely fall by about 33%, and is therefore likely to cause a 10% increase in retail price. As a highly processed farm product, grapes account for only about 10% of the retail price of wine. We use an average elasticity of demand for wine grapes of about -0.5. We estimate that California makes up about half of the relevant market for U.S. wine sales, with imports comprising much of the rest. The reduction in grape quantity of only 1% due to the drought reflects the relatively low share of water costs in grape production costs and the limited supply flexibility for a perennial crop. These parameters imply the drought is likely to cause an increase in the retail price of California wine of about 0.10%.A convenience sample of 300 field workers was recruited from 15 farms in agricultural regions of California’s Central Valley during the summer of 2014. To gain access to the work sites, we invited employers to participate in the study through outreach at local meetings and events, flyers, and word of mouth. About 30% of the farms we approached agreed to participate in the study. Bilingual, bicultural field staff recruited employees of the farms by explaining the purpose and protocol of the study in Spanish and obtained consent. Eligible participants were 18 years of age or older, worked in the fields for at least 6 hours per day, understood Spanish and were neither pregnant nor had any impediment to swallowing the ingestible sensor .

All eligible participants who volunteered were enrolled in the study for a single day of data collection and were given a small monetary gift of appreciation. Preshift measures—A brief, preshift questionnaire was administered orally in Spanish to assess participant eligibility and to collect demographic information. A capillary blood sample was taken and analysed using the handheld i-STAT point of care test to measure serum creatinine . The i-STAT measurements are traceable to isotope dilution mass spectrometry through the standard reference material SRM967.Weight was measured in a base layer of clothing using a Seca 874 medical scale, and height was measured without shoes using a Seca model 213 stadiometer . Field staff recorded base layer clothing to ensure that the participant wore the same garments for weighing after the shift. Participants swallowed a CorTemp HT15002 ingestible wireless temperature transmitter probe . The probe transmitted core temperature at 1 min intervals.Participants were fitted with a Polar T31 ECG heart rate transmitter around the thorax which transmitted heart rate measurements at 1 min intervals. Signals from the probe and the heart rate strap were recorded using a CorTemp HT150016 Data Recorder attached to their belts. All staff involved in data collection were trained and supervised, and all equipment was regularly calibrated to ensure accuracy. Post shift measures—Following the work shift, ~7–12 hours after ingestion of the CorTemp, workers returned to the data collection station and unloaded all external equipment. They were then reweighed in the same clothing as they wore during the preshift weight, prior to ingesting any water or refreshments. A post shift questionnaire was orally administered in Spanish to obtain information on health history and possible social and behavioural risk factors, such as a personal or family history of kidney disease and work history. A second capillary blood sample was obtained to document serum creatinine, and glycated haemoglobin was measured using a Siemens DCA Vantage Analyzer . A single blood pressure was obtained in the seated position using an automated blood pressure cuff . Participants’ BMI, blood pressure, diabetes risk status and blood creatinine level were shared with them at the conclusion of the day, and participants who had abnormal results were referred to local health clinics for follow-up care.

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The coordinate system used to define the parent model was NAD83 California Albers

The Sacramento River is a vital source of water for landowners and irrigation water suppliers in the Colusa Subbasin in addition to providing 80 percent of inflow to the Sacramento-San Joaquin Delta . The Glenn-Colusa Canal originates from the Sacramento River and flows through the Colusa Subbasin into Colusa County via the local canal system, providing irrigation water for the Glenn-Colusa Irrigation District, which is the largest irrigation district in the Sacramento Valley . The only principal aquifer in the Colusa Subbasin is contained in the freshwater-bearing sediments and stream channel deposits of the Modesto Formation, Tehama Formation, Riverbank Formation and Tuscan Formation, with the majority of the fresh groundwater in the project area contained within the Tehama Formation . Soils conducive to recharge, based on the SAGBI rating, range from excellent to very poor suitability, with the most suitable soils in the project area falling within the good to poor suitability range .Hydrologic conditions of interest in the project area include a natural cone of depression in groundwater elevation levels in the middle to southern half of the parent model domain . Based on recent groundwater monitoring data from the California Department of Water Resources , seasonal variations in groundwater elevation contours show a cone of depression forming in the center of the parent model domain during the Fall 2020 season due to stresses to the aquifer, such as excessive groundwater pumping for agriculture during the summer. Groundwater levels usually recover in the springtime, depending on how much precipitation occurred during the winter, but Spring 2021 contours still show lower groundwater levels in the same area with steeper groundwater head gradients,plastic garden pot as opposed to other areas in the parent model domain. Groundwater typically flows away from topographically high areas like the foothills of the Coast Ranges in the west, away from the Sacramento River in the east, and flows towards the topographically low areas where the cone of depression forms.

This area is heavily influenced by agriculture, and high amounts of pumping for agricultural use may be the cause of groundwater level depletion and the subsequent formation of the cone of depression and areas of low groundwater elevation.In 2019 and 2020, TNC recruited several landowners into their fall season bird habitat and ag-MAR incentive program. A total of 8 field sites were enrolled in TNC’s incentive program, which are all located in Colusa County, California . The nearest major cities to the ag-MAR sites are Williams, Colusa, and Meridian. The field sites modeled in this study are located near the city of Meridian, along the western bank of the Sacramento River . The fields are part of the Davis Ranches property. This area was chosen for the child model domain because Field 2 was the only field site that participated in flooding during consecutive years . The crop type grown on these fields is rice, but the fields were fallow during the period of flooding during the fall. The SAGBI recharge rating for the area in and around Field 2 and Field 15 are good to moderately good suitability for deep percolation in the soils .The data collected and used for the two groundwater models were primarily extracted from the Sacramento Valley Groundwater-Surface Water Simulation Model , which is similar to the California Central Valley Groundwater-Surface Water Simulation Model . Both SVSim and C2VSim were developed by the California Department of Water Resources, but SVSim is more specific to the northern Sacramento Valley, while C2VSim encompasses the entire Central Valley. Other sources of data include the California DWR, the United States Geological Survey , and Davids Engineering, Inc., the consulting company hired by TNC to conduct the field methods and technical analysis of the recharge program at each field site during 2019 and 2020. The data extracted from these sources were used in the MODFLOW model development process for parameterizing the packages for the parent and child models. More information on the development and calibration of C2VSim and SVSim can be found in Brush et al., 2013, and California Department of Water Resources, 2022, respectively. Layer stratigraphy data was extracted from SVSim, as were the layer and aquifer parameters, such as specific storage , specific yield , and vertical and horizontal hydraulic conductivity .

The layer stratigraphy and parameter data were used to define the aquifer parameters of all 9 groundwater model layers in both the parent and child models in their discretization packages. The uppermost layers in both models are relatively thin, with an average thickness ranging from 10 to 50 m. The lower layers are the thickest, ranging from about 50 to 200 m thick. The total thickness of all layers combined in both models is approximately 600 m . Each field site was flooded with a depth of 4 inches of water maintained for 30 continuous days during the fall, and 60 days of deep percolation data was collected , with deep percolation rates calculated for each site . These calculations were made using a mass balance approach – in which the inflows to the system are equal to the outflows – along with groundwater level measurements that were taken either periodically or continuously throughout the flooding period at groundwater monitoring wells adjacent to the field sites . Recharge took place at Field 2 during two periods, 9/18/2019-11/16/2019 and 9/17/2020-11/16/2020. Recharge took place at Field 15 during one period, 9/18/2019-11/16/2019. The average recharge rates at the three field sites ranged from 0.011 to 0.023 m/day . Deep percolation rates for all other days, or model stress periods, in the remainder of the domain are rates averaged by month from SVSim. Davids Engineering also monitored groundwater levels in four wells adjacent to the field sites . We used the groundwater level data provided by Davids Engineering for our child model’s head observation package. The average depth to groundwater between all four of the monitoring wells ranged from 5.3 to 7.7 m of depth . The software used for the models constructed for this study is the MODFLOW-2005 Three-Dimensional Finite-Difference Ground-Water Model developed by the U.S. Geological Survey . MODFLOW-2005, hereafter referred to as MODFLOW, uses packages that simulate the effects on groundwater flow processes of wells, rivers, lakes, and other relevant aspects and boundary conditions. A list of the packages used in both models is included in Table 4. MODFLOW can also vertically simulate aquifer systems with different geologic layers that may be specified as confined or unconfined. MODFLOW’s mathematical solution for simulating groundwater flow through the center of each cell in a model follows the partial-differential groundwater flow equation .The larger of the two models developed for this study was a steady state model that encompassed most of the area of Colusa County . As is the case with steady state models, all model parameters remained constant over a specified amount of time,draining pots so all input data that varied over time were averaged to one value for input.

The purpose for making the large model steady state was to have all inputs to the system equal to the outputs, stabilizing the system as a whole. This provided a more general simulation of the regional hydrologic processes , which allowed for faster model runs and processing times. The results of this large steady state model provided information on flow magnitude and direction that was used to constrain the boundaries of the child model. The domain for the large model spans an area of approximately 160,000 square meters and includes 9 layers, modeled after the layers in SVSim.The parent model has 140 rows and 113 columns, with a cell size of 400 m × 400 m. The number of stress periods, or days, is 1 since the parent model is run under steady state conditions. The boundary conditions used to define the model domain include 2 general head boundaries , 2 constant head boundaries , and the river package to simulate the effects of rivers, streams, and canals that flow through the model domain . The smaller of the two models developed for this study was a transient model that was located within the area of the parent model domain, including the ag-MAR field sites . Since the child model is transient, all data input for each package varied over time. The starting date of the child model was defined to be 8/18/2019, one month before the flooding occured, and the end date of the model is 11/16/2020, the last day of the flooding period. Like the parent model, the coordinate system used to define the child model was NAD83 California Albers. The child model has 58 rows and 58 columns, and each cell in the model has a size of 100 m × 100 m. The number of stress periods, or days, included in the child model is 456. Groundwater fluxes and directions of flow were extracted from the results of the parent model in order to inform the boundary conditions of the child model . The well package was used to simulate those fluxes. We defined the flux from each well in all model cells on the child model’s boundaries to represent the general flow that occurred in the same area of the parent model. In more specific terms, cell-by-cell flow data was extracted for each cell in every layer from the parent model, and the cell-by-cell flows were used to inform the groundwater fluxes at the boundaries of the child model. We also used the River package to represent the small part of the Sacramento River that acts as the eastern boundary of the child model. However, the RIV package is only present in the first layer of the model, so we used the GHB package for the eight layers directly below the river cells. The recharge package was used to represent the 2019 and 2020 ag-MAR field sites, with deep percolation data from Davids Engineering.Three different scenarios were run using the child model to test different parameters and their influence on the hydrologic response seen in the model outputs. The three scenarios were designed to assess whether the timing, frequency, and amount of recharge significantly influences the hydrologic results of the child model. Scenario 1 was the baseline model run, using the original and unaltered deep percolation data from Davids Engineering. No alterations or calibrations to the model inputs were made for this scenario. For Scenario 2, we increased deep percolation rates from Davids Engineering by one order of magnitude to ascertain whether we could see a significant hydrologic response. Only the deep percolation data was altered for Scenario 2; all other inputs remained the same as Scenario 1. It should also be clarified that a tenfold increase in recharge rates is not realistic. However, we wanted to test this hypothetical extreme solely to see a significant response. For Scenario 3, we increased the duration of recharge to span ten years.

We chose to use the 2019 deep percolation data, and repeated that year ten times to see how increasing the duration of recharge would affect the child model results. The 2019 deep percolation data input for Scenario 3 was unaltered; only the duration of recharge and the time discretization of the child model was increased to span ten years. Scenario 3 was designed to represent ten consecutive years of implementing ag-MAR on these field sites.The results analyzed from the steady-state parent model include model performance plots and model outputs. We assessed the performance of the parent model with a one-to-one plot of the observed heads that were input into the model, with the simulated equivalent heads that the model calculated at each groundwater monitoring well in the parent model domain . The different colors on the plot represent the binned data of the residual heads, which were calculated as the difference between the observed and simulated equivalent heads. The different bins represent different groups of residual data ranges. The gray line represents the line of equal values, or one-to-one line, between the observed and simulated equivalent heads.The same binned residual head data were plotted on a map of the parent model domain, showing the location of the groundwater monitoring wells and the residual head value . Like the residual head bins plotted in the one-to-one plot in Figure 12, the bins for the residual map were calculated from the difference between the observed and simulated equivalent head values at each groundwater monitoring well on the map.

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Trees and other types of vegetation are then planted in this new built environment

In the case of citrus, for instance, a globally important fruit crop that is often heterozygous for important trait genes, protoplast regeneration can be achieved only if protoplasts are derived from juvenile tissues. However, plants generated from juvenile citrus tissues require years to reach a mature fruit production stage, and this delay is an impediment to the efficient evaluation of gene functions in fruit and for other genes pertinent to citrus breeding programs. On the other hand, tissues from mature citrus trees, such as shoot segments, can be transformed with Agrobacterium. Jacobs et al.discussed the possibility of using Agrobacterium-mediated transient expression of Cas9 and sgRNA genes to produce non-transgenic mutant plants. Iaffaldano et al.reported the production of CRISPR/ Cas9-mediated mutant plants using Agrobacterium without any selection of stable transgenic plants. However, Iaffaldano et al.did not characterize whether their mutant plants were transgenic or non-transgenic, nor did they calculate the percentage of each type. The nontransgenic mutation rate reported in this study is lower than mutation rates for the previously reported protoplast micro-injection methods but higher than for particle bombardment methods. However, Agrobacterium can be a more versatile tool because of its ability to efficiently infect many different tissues types across most plant species, and it is the most widely used method for plant transformation. Thus, protocols for Agrobacterium infection and subsequent callus and shoot regeneration are readily available for many crop plant species. Furthermore, even when other methods are applicable, Agrobacterium infection procedures are relatively simple and easy to perform for many plant species. Thus,draining pot the method presented here provides an alternative method for the production of non-transgenic mutant plants.

Our method of using Agrobacterium to transiently express CRISPR/Cas9 genes, without the use of chemical selection such as kanamycin, also offers some other advantages. The lack of a chemical selection agent following Agrobacterium infection allows for even greater rates of plant regeneration compared to when chemical selection is used and therefore likely enhances mutant callus/shoot production. This is because selection agents, such as kanamycin, hygromycin, and various herbicides, can suppress shoot regeneration for many plant species, even when those shoots express relevant resistance genes. Furthermore, our high-throughput screening method, based on a novel DNA sequencing strategy in combination with HRM analysis, makes mutant identification fast and easy to perform. The drawback of our method is that there is a risk of creating transgenic mutant plants; however, identifying and discarding these plants does not add any significant time to the screening process. We have observed that the threshold of mutant plant detection using the Illumina sequencing method can be much more sensitive than the detection of one mutant out of 42 plants described in this study. The use of the 42-plant sample pools, therefore, assures that the presence of a mutant plant can be readily detected in pooled samples. Additionally, the threshold of HRM analysis to detect mutant plants can be as low as 1 of 19 plants, but we chose one out seven . Again, this pooling choice provides a safe margin for error by reducing the chance of missing mutant plants due to false negatives. Furthermore, a small number of false positives from the sequencing analysis of 42-plant pools are not a concern because they can be easily identified in the subsequent step of screening. Thus, our method, which combines a unique DNA sequencing strategy with HRM analysis, provides a reliable protocol to screen for CRISPR/Cas9-mediated mutant shoots from a population of shoots regenerated in the absence of selection pressure. The overall protocol for mutant identification is schematically represented in Supplementary Figure 4.

Using this protocol, it would take ~14 days to identify all mutants from 1000 independent shoots that were subjected to Agrobacterium-mediated transient expression of CRISPR/Cas9 genes. In conclusion, we have developed a highly useful method utilizing Agrobacterium-mediated transient expression of Cas9 and sgRNA genes combined with multi-step pooled screening, enabling the reliable production and efficient identification of non-transgenic mutants regenerated in the absence of selection pressure. Due to the versatility of CRISPR/Cas9 and Agrobacterium-mediated infection, as well as the ease of plant regeneration from leaf, shoot, or root explants, this method is applicable to many economically important plant species, particularly heterozygous perennial plant species that are recalcitrant to regeneration from protoplasts or following biolistic bombardment.Urban trees are garnering increasing attention in this era of interest in biodiversity and urban sustainability. There is growing recognition that urban areas are largely the result of human decisions and actions – they are constructed spaces. When cities are designed and built, for example, local vegetation is usually removed, and the earth recontoured and/or excavated to facilitate construction.The species chosen can be culturally, historically, or functionally significant, but it is logical to think that species planted are generally representative of species available from the local nursery industry at the time and may or may not draw from the native flora of a regional ecosystem . Regional nursery catalogs as a data source for urban biodiversity have not been evaluated prior to this research. Yet, the horticultural industry has been shown to be an important contributor to regional biodiversity with regard to invasive species distributions . This paper contributes to the literature on urban biodiversity by suggesting that plants offered by nurseries are a source of yetto-be-explored diversity in cities. We hope that this research will encourage the further consideration of the role of nurseries in urban biodiversity. The significant historical legacy of tree introductions by European and Eastern U.S. settlers in California likely accounts for the initial urban tree diversity of Los Angeles and Southern California. The early 17th-century missionaries came with a culture of planting both crop-yielding and ornamental trees and this tree palate was substantially supplemented with the advent of the intercontinental railroad and increased oceanic traffic connecting Southern California with the world in the 19th Century.

An innovative horticultural industry emerged in California which both catered to, and shaped the tastes of, settlers . Today Los Angeles has an exceptionally diverse tree assemblage where the imprint of this early period can still be detected. Referred to as the Garden of Eden, Paradise, and the Garden of the Hesperides throughout its relatively young history, images from this region spread worldwide . There are a number of historical and social factors that can shape and influence tree species composition and diversity in cities beyond biophysical ones such as climate, environment, and ecological factors . Cultural factors , and factors related to symbolic and representational associations of trees are also important. However, one possible critical factor in the planting and distribution of trees in the urban environment that has not been investigated previously, and is certainly related to the factors above, is the selection of tree species available from the nursery industry of the region. People obtain trees from purveyors,round plastic planters and thus this article examines the evolution of the selection of trees available from tree nurseries and seed availability. If there is no stock or seeds locally available, the burden of finding a desired tree is much higher. Thus we suggest that a window into which trees are found in the urban fabric may be by examining nursery catalogs over time. This paper describes results from a longitudinal study of nursery offerings of tree species from 1900 to 2010. Los Angeles County has around 6 million trees in a bio-region that naturally supported trees only along riparian corridors and along the foothills of the cityregion . As Schoenherr and Rundel and Gustafson have documented, in pre-colonial cismontane Southern California was dominated by chaparral and coastal sage scrub. Trees were mostly found in riparian corridors and along the foothills and included 14 native species. To understand the role of the landscape nursery industry in influencing diversity of the tree canopy cover, we developed three main areas of inquiry. First, we examined whether there has been a significant change in the number of tree genera and species offered by tree nurseries over time. Second, we asked whether there have been significant changes in the functional classifications of trees offered over time. Finally, due to the size of the data set we were curious to know whether some species had been offered consistently from the early 1900s to 2011.The limited historical documentation available from the California Department of Food and Agriculture was supplemented with archival catalogs. We located two nursery catalog collections in the region: Collection of Nursery Catalogs in the Department of Special Collections located in the Charles E. Young Research Library, University of California, Los Angeles, and the collection of catalogs available at the Los Angeles County Arboretum and Botanic Garden Library. The 2009 and 2011 catalogs of West Covina Nurseries and Monrovia Nurseries, both large and well known nurseries in the region, were accessed on the company’s websites respectively . We exclusively utilized catalogs of nurseries located in Los Angeles County. Data collection involved manually transcribing tree species information from each catalog into a database for further analysis. Species that were 12 feet and taller were classified as trees in this analysis. Images of the catalog pages were scanned and converted to text using optical character recognition software. The location of the nursery, the year of the catalog, scientific name, and names of varieties were recorded. Information was also collected for commercial fruit trees but is not included in this analysis. In order to classify the tree as deciduous or evergreen, native or non-native , angiosperm or gymnosperm, we used the Sunset Western Garden Book . Gymnosperms were classified as tree species belonging to Araucariaceae, Cupressaceae, Ginkgoaceae, Pinaceae, Podocarpaceae, Sciadopitayaceae, and Taxaceae families .

Tree fern species were classified as ferns. Catalogs were chosen to represent every decade from the 1900s to the 2010s. This 110-year period was split into four periods of 30 years each in order to conduct the statistical analysis, because the numbers of catalogs represented in each time period was different . A total of 18 unique nursery catalogs were sampled for this research. The number was restricted by availability in the archival collections. The number of catalogs sampled in each time period differed such that period one had three catalogs, period two had four catalogs, period three had six catalogs, and period four had five catalogs. We streamlined the study design by sampling at least one nursery catalog to represent each decade . While it is likely that having more catalogs, and in turn, having a larger sample size, especially in the earlier decades, would have yielded more robust trends and results for the earlier decades, it is unlikely this would have changed the overall results.The large data set was then analyzed using both Microsoft Excel 2011 and MATLAB 10. MATLAB was used to obtain specific numerical information . Using a statistical count model we were able to predict the number of species offered in each time period; we suspect that the difference in number of catalogs sampled would have little to no effect on the actual number of species offered, thus the overall result would still not change. The entries were optimized manually to account for spelling errors, alternative names, and repeats. In order to compare the time periods and the different numbers of catalogs sampled in each time period, we employed a negative binomial regression count model. This allowed for comparison between time periods by predicting the number of species offered in each time period. One goal of the analysis was to identify whether there was a statistically significant difference in the number of species throughout the time period, and we found there was with a 95% confidence interval. A polynomial contrast was used to detect linear and quadratic trends with time. An exponential model was also used to analyze the same data. However, unlike the count model, the exponential model did not take into consideration the difference in the number of catalogs used in each time period. While the results indicated that both models fit the data, we chose to use the negative binomial regression count model because it took into consideration the differences in the number of catalogs used in each time period.We also found that there were fifteen species offered consistently in every decade.We used the nursery catalogs to identify wholesale and retail nurseries, and city websites to identify cities that had municipal arborists.

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Sustainable development is now globally accepted as a supreme long-term goal of humanity

The recent publication of two almond reference genomes and the increasing availability of quality genomic data opens opportunities to complement our study and obtain more complete and accurate pedigrees based on genomic variability. This kind of studies can be useful even when some genotypes were discarded due to breeding process, as is the case in our almond pedigree work. Although almond showed a higher genetic variability than other Prunus species, the historical expansion of almond from the Mediterranean region to California and from California to Australia could have caused a bottleneck effect in the breeding population under study. Different studies have reported a high genetic relatedness between Australian and Californian cultivars, possibly caused by the introduction of a limited number of cultivars from Europe to these countries. In addition, breeding programs worldwide have used cultivars from French origin as main founders as Aï, Princesse, Ardechoise, Nonpareil, IXL, Ne Plus Ultra, or Nikitskij. This situation could have led to an underestimation of relatedness and inbreeding. The use of large-scale genomic data would provide most valuable information in this respect,plastic pots plants expanding the almond pedigree beyond breeding records.Man’s interaction with nature is rapidly becoming more complex due to a multitude of activities that directly or indirectly cause a disturbance in the natural system. The deeper interactions between human activities and natural ecosystems call for an interdisciplinary approach to natural resources management, while the inputs from multiple disciplines need to be effectively utilized in achieving it. This prudent natural resources management will enable sustainable development of a region without losing the resource base. Sustainable development essentially aims to reconcile conflicting objectives of economic development and improvement in human welfare, and ecological sustenance and functioning of ecosystems.

The term sustainable development is defined by the Brundtland Commission as “the development that constitutes meeting needs of the current generation without compromising the ability of meeting needs of future generations” .Sustainable utilization of natural resources is essential for sustainable development. It follows that the sustainability of renewable natural resources in general and common property resources in particular assumes importance in both developed as well as developing countries because of the finite capacity of the resource base and the increasing demand for its exploitation. The technical definition of the term sustainability is given as, “the ability of a natural resource system to produce a socially optimum level of output that is necessary to meet the needs and aspirations of the people dependent on the system perpetually without any detrimental effects on the resource system itself and the physical environment, and with no imposition of significantly greater risks on future generations” . This might be comprehensive and deep rooted, but in other words, sustainability implies not only conserving natural resources but also maintaining ecological functions and the supply of natural resource products, which are essential to the livelihoods of local people. Sustainability in this sense is a dynamic concept that reflects changing levels of output corresponding with changing human needs and production technologies over time.Natural resources discussed here are broadly covered under land, water, and biomass . These three resources are crucial for production under various systems namely, agriculture, horticulture, silviculture, pisciculture, and animal husbandry. Management of these three major resources is crucial for making production in these systems sustainable and enhanced. Sustainability of these systems can be threatened due to disruption in the linkages between these resources. This may assume various forms, for example, increased soil erosion resulting in nutrient loss rendering it unfit for use in the case of land; soil water deficiency or excessiveness affecting its productivity and degradation in the case of water resources; decline in vegetation density and diversity leading to reduction in soil and water conserving properties in the case of biomass or vegetation resources, and so forth. A more detailed discussion of these follows.

Soil productivity can be defined as those properties of soil that influence crop production. The increased yields from better-managed soils are due to increased inputs and improved practices rather than with improvements in the basic fabric of soil . In recent years the sediment derived from soil erosion has been the major non-point source of pollution in surface water bodies while loss of in-situ topsoil has caused reduction in productivity. Erosion reduces long-term production potential and seldom improves the immediate capacity of eroded soil to sustain plant growth or produced crops . Results of recent studies show that soil physical and biological properties seem to be the predominant constraints to maximizing plant production on eroded soil, compared with chemical and fertilizer constraints. For example, Rosenberry, Knutson, and Harmon suggested that yields generally decline as soils shift from one erosion phase to another, even with increased fertilizer. This is attributed to surface soil physical and biological properties. However, in addition to irrigation, other water management techniques, such as surface mulching, can also be applied for amelioration of eroded soil. Crop productivity is also affected by moisture availability in soil. In the post-green revolution, particularly in the 1980s, instability in crop productivity increased on account of the rise in sensitivity of output to variations in rainfall in India . This increasing vulnerability of agricultural output to variations in rainfall, particularly during droughts when the soil moisture is scarce, is attributed to inadequate expansion of irrigation by these same authors. It is minor irrigation, which is not given priority that can be part of the strategy under watershed development. Similarly, decline in water quality has affected crop productivity in saline and alkaline lands that were created by excessive irrigation or polluted water in northern parts of India. At the same time, vegetation adds much to resource endowment and has crucial linkages with soil and water. Good vegetation cover functions as a soil and water-conserving agent, whereas, lack of vegetation will make the soil vulnerable to erosion and allow water to flush off the sediments. Biological diversity of vegetation is crucial in the survival of the vegetation itself and the sustenance of the ecosystem in that region. In fact, planning based on land use can effectively conserve soil as well as water. This is little elaborated under Production Systems Planning .

A distinction, however, needs to be made between the goals of attaining sustainability and of increasing productivity. While higher productivity may be required to achieve the sustainability goal, the requisite increase in productivity must be achieved in a manner that will not jeopardize the ability of a natural resource system to meet future needs. In other words, it is possible to achieve increases in productivity through unsustainable short-term approaches . The term watershed denotes the area defined by natural boundaries characterized by terrain , soils, and drainage delimitations. Watershed is an appropriate unit for environmental planning for sustainable management of natural resources of a region. Watershed Management is a practice of conserving soil, water, and biological resources using scientific principles,plastic nursery pots traditional and systems knowledge, and local resources with an objective of increasing crop productivity. It involves rational utilization of land and water resources for optimum production with minimum hazards to national resources. It essentially relates to soil and water conservation in the watershed which means land use according to land potential, protection of land against all kinds of deterioration, building and maintaining soil fertility, conserving water for farm use, proper management of water for drainage, flood protection, sediment reduction, and increasing productivity for all kinds of land uses . Watershed management has come into focus in India with the advent of productivity fluctuations with rainfall, necessitating micro-irrigation in drier parts, and also with the advent of space technology tools, which are useful in the micro-level planning. Land water related management projects and schemes have been implemented under various programs since the beginning of the Five Year plans. In particular, the third Five Year plan introduced the watershed as the basic hydrological unit for soil conservation planning and execution . Increased emphasis on watershed development programs for dry land plain regions in India, inter alia, is a manifestation of the shifting priorities in the agricultural sector, which until recently concentrated mainly on crops and regions with assured irrigation . Successful case studies of Ralegaonsiddhi, Myrada, are well known . In the sequence of evolution of natural resources management using the watershed approach for sustainability of these resources, thrust is on the productivity of natural systems. It is the productivity of natural systems that needs to be conserved through planning so that the needs of an increasing population are met and the threat to their renewability is thwarted. The watershed approach is an ideal approach to carry out a planning operation, and its planning framework shall fit well under the implementation and execution activities. Central to the success of the process is the participation of the population during the crucial implementation. Production systems planning is a method of planning for the use of natural resources under the watershed approach with a focus on ecological characteristics. It essentially involves spatial allocation of land use for various production systems, namely, agriculture, horticulture, and animal husbandry, by which conservation goals are met through better decision-making. PSP is similar to regional land use planning, but it differs from it in that it depends on ecological characteristics at the watershed level rather than activities at the regional level. However, in both cases land use is an important element.

The role of production systems in soil and water conservation is evident from the water and soil losses of catchments under such production systems such as mentioned by Mallik . Fruit development is mediated by plant growth regulators that control its major developmental processes. As grape berries develop, they exhibit a double sigmoid growth curve separated by veraison that marks the beginning of ripening. Cell division and expansion are the major events during the first phase and are accompanied by synthesis and accumulation of organic acids, methoxypyrazines, and phenolic compounds such as proanthocyanidins and hydroxycinnamates. This phase of berry growth is under the control of auxins, gibberellins, and cytokinins. Auxins and gibberellins are mostly produced by the seeds while the source of cytokinins in fruits is less established and it is likely to be imported from the plant. The number of seeds in the berry can determine berry size, and the lack of seeds or the presence of unfertilized ovules in sternospermocarpic berries can be partly complemented by external gibberellin. Schematic representation of the levels of PGRs during development suggests that auxin levels are high at berry set and decrease during phase 1 while cytokinins and gibberellins peak during phase. The second phase, verasion, marks the beginning of major processes in grapes ripening, berry softening and anthocyanins accumulation in colored varieties. There are reports of a small peak of ethylene preceded by a large peak of abscisic acid which coincide with veraison. Brassinosteroids increase at veraison and participate in ripening, possibly by modulation of ethylene content. On the other hand, auxin treatments retard sugar andanthocyanin accumulation and prevent the decrease in acidity and chlorophyll concentration, and also cause a delay in the usual ripening-associated increase in the levels of ABA. The third phase in berry development is ripening which is characterized by accumulation of glucose and fructose, as well as a decrease in the levels of organic acids. Volatile compounds that are produced by grape berries during development and ripening include fatty acid derivatives that are the most abundant group, monoterpenes that are prominent flavor compounds in Muscat flflavored grapes, sesquiterpenes, C13 norisoprenoids, volatile sulfur compounds, and methoxypyrazines. Some volatile compound types such as methoxypyrazines and sesquiterpenes, C13 norisoprenoids and volatile fatty acid derivatives accumulate in the berry before veraison while volatile monoterpenes and volatile sulfur compounds accumulate during ripening . Physiological studies on the role of PGRs in fruit development often rely on external applications of the hormones or their agonist followed by observations of the changes in fruit development. In table grapes there is a plethora of applicative studies aimed at increasing the berry size in ‘seedless’ varieties and the color of red varieties grown in hot regions. The effect of GA was studied from the late 1950s with timing and concentration being major factors. In ‘seedless’ grapes, application of GA to increase berry size is performed at a fruitlet diameter of 4–6 mm because earlier application can have negative impacts on fruit-set and berry shot and later application is less effective.

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Enhancing tree nutrition has also been reported to increase fruit set rates

In the post-independence period India relied on Green Revolution technologies to increase production of staple cereals such as wheat and rice. This historical approach to ensuring food security has repercussions for contemporary conversations about hunger. Namely, my interlocutors considered national food insecurity to be an issue of the past. As an official in the Karnataka Department of Horticulture told me, India has now achieved food security due to the impact of Green Revolution technologies. He said that after independence, India was most concerned with becoming self-sufficient in food grains, and was unconcerned with the long-term effects of inputs like pesticides and hybrid seeds: India was “not concerned with [food] quality” because quantity was the most critical concern. However, in the 1980s, he suggested, the Indian government began thinking about how to provide “high-quality foods,” once the “rush to feed more people was lessening.” Between the production plateau of the 1990s and the increased knowledge about the effects of pesticides on human health, he said, India must now think more about food quality than quantity. This narrative—of achieving national food security and turning to other concerns—is linked with a broader understanding of the changing economic landscape in post-liberalization India. The majority of my interlocutors were preoccupied with two problems in this context: the “agrarian crisis,” and rising food safety and health concerns. While these problems affect diverse actors, they are primarily the concerns of the middle classes. Sociologist A. R. Vasavi has shown that the agrarian crisis—characterized by debt and economic insecurity that she attributes to the individualization of risk in the post-liberalization period—most severely affects small landowners. These forms of agrarian distress do not capture the insecurities of the poorest and most marginal members of agrarian communities,garden plastic pots including landless laborers and subsistence farmers .

Efforts to address the agrarian crisis are thus focused on addressing the concerns of landowners. Similarly, as I argue in chapter 3, the farmers who benefit from the creation of new intermediary forms are neither the most privileged nor the most marginal members of their communities. Just as the concerns about agrarian distress and the projects that they motivate are anchored in the middle strata of agrarian society, efforts to ensure food safety are rooted in middle class concerns and desires. In India today, fears about food contamination and adulteration are on the rise, and food safety scares generate intense concern about food quality and health. These concerns are not restricted to the middle and upper classes—the Maggi noodles scandal in which Nestle’s immensely popular packaged noodles were found to contain undisclosed MSG additives and above-threshold levels of lead caught the attention of a wide swath of the public, likely because these noodles are consumed across class, caste, and religious divisions . However, as I show in this dissertation, companies that claim to provide “quality” fruits and vegetables—a claim that is often conveyed through third-party certification programs like organic or GLOBALG.A.P—target the urban middle and upper classes. More accurately, they cater to consumers who are members of the established middle and upper classes. They are justified, however, along the narrative of the emerging middle class and its growing appetite for global foods and awareness about food quality and health. The conversation surrounding both of these problems—the agrarian crisis and food safety concerns—offer certain solutions in favor of others, and in so doing, address some challenges and audiences rather than others. Specifically, I show that the two interventions considered in detail in this dissertation—the creation of new intermediary companies and gardening among urban professionals—are class-specific answers to class-specific problems. This point is critical because these projects establish new forms of food distribution that will replace or reconfigure Bengaluru’s supply chains. In this way, these projects are part of the same patterns of exclusion and dispossession at the heart of urban development policies that privilege middle class concerns and desires .

This dissertation offers ethnographic insight into shifting food supply chains in order to understand how changing urban and agro-environments, class structures, production methods, and consumption patterns intersect in class-specific experiences of Bengaluru’s shifting food ecologies.This is in part due to the inextricable relationship between food, the body, and place. As scholars have long identified, food is a symbolic and material force that transcends and delimits particular places and communities.Appetites and aversions are inseparable from power structures . In his essay on “gastropolitics,” Arjun Appadurai details what he calls “the biophysical propensity of food to homogenize the human beings who transact through it” . In the South Asian context, this propensity makes eating a particularly powerful, and potentially transformative, practice. Food is at the center of South Asian understandings of self and other, and, as Appadurai suggests, the limits of this distinction. The “homogenizing” qualities of food lend a particular character to concerns about food safety and health that are closely linked with place. Harris Solomon argues that experiences of ingestion are central to how urban Indians understand and mediate risk in their daily lives. He uses the framework of metabolism to consider the porous relationship between bodies and the urban environment in Mumbai, suggesting that concerns about obesity and food safety are connected with the lived experiences of life in the city. The homogenizing and porous qualities of food are realized not only through ingestion, as Appadurai and Solomon each identify, but also through supply chains, as forces that link, for example, fields, delivery trucks, store shelves, and bodies. In the processes of supply chains, objects, environments, and practices blur. For example, as sites for production and processing practices that are undetectable to the end consumer, supply chains illuminate the intimate yet often invisible relationships between actors embedded in the food commodity. It is in this porosity that supply chains illuminate the inequalities, insecurities, and aspirations that characterize shifting food ecologies.

While the majority of existing analyses of food supply chains focus on global markets and commodity networks, this dissertation analyzes the regional fresh fruit and vegetable supply chain that connects urban consumers in Bengaluru with nearby farmers. Focusing on the regional fresh fruit and vegetable supply chain opens up a critical issue that speaks to larger questions about what makes food “good”: the proximity between producers and consumers. In India today, managing the circulation of highly perishable commodities remains a challenge—refrigerated transportation is rare, as are infrastructures such as ripening chambers, and basic utilities such as electricity remain sporadic. These limitations mean that highly perishable food is necessarily local. Given the rising influence of the local food movement that envisions local supply chains as an answer to the ills of the industrial food system , India offers an interesting case study to understand the potential manifestations and effects of highly localized supply chains. It also opens up new ways to interrogate the discourse of locality shaped by the local food movement: How do the geographic mobilities and temporal rhythms of the supply chain change between perishable and non-perishable food commodities? What different understandings of locality, quality,raspberry plant pot and authenticity are produced in a place where supply chains are largely restricted by the inefficacies of infrastructure rather than the desire to “go back” to localized food networks? What relationships between farmers and urban consumers emerge in this context? The last question gets at a key dynamic at the heart of this dissertation: the changing relationship between the country and the city in the context of a rapidly expanding cityscape. The relationship between the city and its outlying communities has consequences for ecologies and economies that transcend the categories of urban and rural. Supply chains help us envision the interconnections that complicate the urban-rural dualism. William Cronon’s Nature’s Metropolis: Chicago and the Great West sheds historical light on how Chicago’s hinterland was critical to its creation as a metropolis. By following wheat, lumber, and meat into the city, and tracing how urban markets in turn changed the countryside, Cronon argues that the distinctions between nature and culture and rural and urban are artificial. Rather, the natural resources of the countryside are instrumental to the city-building process. Similarly, this dissertation follows fruits and vegetables to trace the interconnections among agrarian and urban communities. I show that urban consumers’ insecurities and desires are inextricably connected with those of peri-urban producers, highlighting the spaces and practices of overlap between the city and its agrarian countryside. However, my goal in so doing is not to refute the lived reality of the rural-urban divide. For the people who occupy spaces categorized as urban or rural, the inequalities embedded in this distinction are very much real, with concrete manifestations in their daily lives. This dissertation engages with these categories and the lived experiences of overlap and divergence in order to explore how city residents and nearby farmers understand and experience the effects of the rapidly expanding cityscape on their present lives and possible futures.

For each, food offers a narrative locus, embodied experience, and site of intervention into the ambiguities of urban development.Alongside the shifting materialities of food ecologies are changing ethical understandings and practices of food and agriculture. In Bengaluru today, the term “market” is used extensively among English- and Kannada-speakers, villagers and city residents alike. For the majority of my interlocutors, the market represents both the problem and solution—access to the urban market provides an opportunity for higher incomes among farmers, but is also a source of widening disparities within and between agricultural communities. Among urban consumers, the market is seen as both the source of contamination and generative of better options. This attention to the market both reflects and informs a wide variety of changes to Indian agricultural commodity markets and their linkages . In India today, the market is understood to be anchored in the laws of supply and demand. However, this coexists with the belief that the government can and should intervene to make the market fairer and more effective. I heard from many farmers, for example, that the government should support them by better connecting them with the market. This approach to the market defies any easy separation between political context, social responsibility, and market forces. Despite the language of the “free market” that sets economic forces apart from the sociopolitical landscape, scholars have demonstrated that markets are in fact performed and produced . Rather than existing in a sphere separate from social norms, markets become sites to contest moral grievances .Grower attention has been focused on increasing orchard yields for decades and research efforts have been aimed at improving almond orchard productivity through the optimization of all variables involved in nut production. Fundamentally, almond tree yields are the product of the number of kernels produced per tree and kernel weights. Of these two factors, the number of kernels is the most important since kernel weight is generally not a factor of paramount importance for growers . The reproductive process in almond trees involves two years from flower bud induction to fruit set and fruit maturity. In this process the number of flowers borne and the number of flowers that set fruit determines the final kernel yield per tree. Fruit set in almond is strongly influenced by presence of pollinizer cultivars, insect pollinators and by climatic conditions affecting pollen viability, germination and pollinator activity in addition to general tree health. In 1959, Kester and Griggs stated that “the question often arises as to whether or not the fruit set for specific almond orchards could be increased by using more bees and pollinizers to effect more complete cross pollination”. Mean relative fruit set in almond has been reported to be about 30% but there is large year-to year variability that can make it range as low as 5% and as high as 40% . These relatively low fruit set percentages offer a potential margin for almond crop improvement. Accordingly, almond orchards are planned and managed to improve relative fruit set by planting pollinizer rows on either side of the main cultivar rows to increase availability of compatible pollen . The use of bees in almond orchards during flowering increases the likelihood of movement of pollen among trees .

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This interpretation correlates well with the position of three TGAT core motifs

Transcription factor binding sites were identified by consulting multiple online prediction tools which quickly found over two hundred predicted cis-motifs, many of which had low probability scores. The odds of identifying functional cis-motifs were increased in a few select cases by adding 5bp sequences on either side of the core motif, based on previously identified target sites for WUS , ARF1, and ARR1. The enlarged biding sites were then mapped to the CLV3 genomic sequence, tolerating up to 2 mis-matches in the flanking regions. In order to account for the presence of transcription factors whose cis-motifs are not currently known, MEME analysis were employed to identify motifs shared between genes that are co-expressed with CLV3. Overall, 231 potential cis-motifs and transcription factor binding sites were identified. Most were randomly distributed over the entire CLV3 genomic sequence, but irregular clusters could be recognized near the coding region. The largest cluster occurred in the upstream 500bp of the 5’ promoter, while up to three smaller clusters occurred in the 3’ enhancer region . The list of potential factors was then filtered to include those found inside the previously identified CLV3 regulatory regions, which left just 157 predictions . Many of the remaining predictions were found to have overlapping sequences, though it is unclear how well this might predict their actual function in-vivo. One notable example of this phenomenon is a predicted MYB-like binding site located at -155bp, which was predicted by four different databases. In other cases, two structurally different transcription factors were predicted to have overlapping cis-motifs, such as the bZIP/homeodomain pair Opaque-2/ALFIN-1 in the 3’ enhancer region. Interestingly,large plastic pots for plants the data also revealed four partial miR414 targets, three of which overlapped with the DNA/Mariner family transposable element At2gTE50670 in the 3’ enhancer , and the fourth occurred in the 3rd exon.

In an alternative approach to identify unknown cis-motifs, phylogenetic footprinting was used to compare CLV3 orthologous sequences from different species. In this method, functional regulatory structures can be identified by their conservation over evolutionary time, which often requires little more than performing a sequence alignment. The method is also quite robust, as previous studies found that the identified footprints matched 80 and 85% of known transcription factor binding sites. To begin this analysis, three CLV3 orthologs were identified by their syntenic relationships within the Brassicaceae using the tools in the Brassica Genome.org database. Their cDNA sequences were aligned with 27 CLE family paralogs identified in A. thaliana in order to identify features that were unique to CLV3 orthologs, before expanding the search to additional species. This analysis revealed three potentially unique traits that might be used to distinguish orthologs from the multitudes of closely related CLE genes. These included three consecutive histidines at the C terminal end of the CLE motif, a C-terminal oligo extension, and a 3-exon gene structure, all of which had been previously identified in the CLV3 sub-group. Additional orthologs were then identified using tBlastn searches against the AtCLV3 protein, for which nine species which met the criteria described above: Brachypodium distachyon, Oryza sativa, Ricinus communis, Glycine max, A. thaliana, Arabidopsis lyrata and Brassica rapa, Capsella grandiflora, and Camelina sativa. No AtCLV3 orthologs were identified in the gymnosperms, basal angiosperms, or the Asteriids using these search parameters. The Euphorbiaceae and Fabaceae each contributed one species in the closely related Eurosiids I, while the monocots are represented by two species in the Poaceae. As a result, this sampling is heavily biased towards the Brassicaceae family , which provide more than half of the total number of species. In order to footprint the promoter regions, initial sequence alignments were performed using 8kb genomic fragments, containing up to 5kb of upstream and downstream sequences on either side of the coding region. However, little or no homology was found when all nine orthologs were aligned simultaneously. This was not improved by removing monocot clade, as the two grass orthologs failed to align with each other.

Repeating this pattern, both R. communis and G. max also failed to alignment with each other, or with any of the remaining orthologs. In contrast, conserved regions became clearly visible when the five Brassicaceae species were aligned separately . This result appears to reflect the optimum degree of sequence divergence for this gene, as previous studies have found that orthologs outside of the Brassicaceae were less informative due excessive divergence, whereas sequences obtained entirely within the Brassicaceae have been found to have too little divergence . Three of the remaining species had complete genomic sequences, while the other two consisted of two contigs separated by a gap of unknown size. In the B. rapa ortholog, the gap was located in the 3’ region, and was flanked by 256 and 452 base pair sequences that did not align with any of the other Brasssicaceae orthologs, despite strong sequence conservation in the surrounding regions. This indicates the recent insertion of a large DNA fragment, potentially >700bp in size. Attempts to locate the source of the two end-fragment sequences in the B. rapa genome with BLAST searches, unexpectedly found that each was present in multiple copies, and were distributed across several different chromosomes. No evidence of transposable element sequences were found, so the flanking regions were here interpreted to be contaminating scaffold sequences from the original genome assembly. A similar gap of unknown size occurred in C. grandiflora, where one contig aligned with the CDS and 3’ UTR, while the entire 5’ upstream contig failed to align with any other ortholog. In both cases, the non-aligning sequences were removed from the analysis, providing a final alignment consisting of four orthologs in the 5’ promoter region, and five orthologs spanning the CDS and 3’ UTR. Overall, the five orthologs shared between 27% and 65% sequence similarity, and grouped into two closely related pairs. One pair contained C. grandiflora and C. sativa, and the other contained A. thaliana and A. lyrata. In contrast, B. rapa was found to be distinct from all other Brassicaceae orthologs, which accurately recapitulates its predicted evolutionary relationship with the rest of the family. Upon closer inspection, the coding regions were found to be 79-93% similar, which dropped to just 14-34% in regions with no significant alignments. The initial alignment was considerably fragmented, with many insertions, deletions, and isolated nucleotides. In many cases, the position of these features varied with the settings in the alignment software, and were here interpreted to be artifacts of the alignment procedure.

To correct such artifacts, isolated nucleotides were manually adjusted left or right to maximize local sequence alignments within ±5bp. Where variation in the length of tandem repeats was apparent, gaps were introduced into one or more ortholog sequences to accommodate the largest number of repeats present. Conserved regions were then identified by using a 5bp sliding window to identify regions with more than 60% identity. This window is unusually small compared to previous studies that have used 15-50bp sliding windows, but was chosen here to more accurately reflect the minimum size of known transcription factor binding sites. Where large contiguous conserved regions were found, the presence of small 1-3bp indels within their sequences were used to break them into smaller fragments, as disruption of these sites indicates that they do not contain functional cis-motifs. scattered in the 3’ UTR. Several predicted transcription factor sites were found within the coding regions, but these were interpreted to be non-functional, as previous GUS-reporter systems did not reveal any significant regulatory elements within this region. Among other notable features was a predicted signal peptide in the first exon, identified with signal P 4.0,blueberry pot which was almost entirely conserved and is consistent with the secretion of the mature CLV3 oligopeptide. In addition, the second exon was found to be completely conserved with no In all, 42 conserved regions were identified, ranging in size from 5 to over 111bp long. Fourteen footprints were found in the coding sequence, of which nine of were clustered around the three exons. Only one footprint was found entirely within in the 5’ UTR, and the remaining four were intervening gaps. The second exon also completely overlapped with several predicted transcription factors, including HOX2a, aswell as cytokinin and gibberellic acid responsive motifs. This suggests as-yet unrecognized functional role for the second exon, which might explain why it has been retained in a family that consists largely of single exon genes. The 3rd exon was also highly conserved, although curiously the most conserved region only partially overlapped with the CLE motif and instead included part of the C-terminal extension. In the 3’ UTR, the footprints were found to overlap with potential zinc-finger and MYB binding sites, as well as a cytokinin responsive ARR10 site. In the upstream regulatory region, the 5’ promoter contained ten conserved footprints, eight of which formed a large and nearly contiguous block near the TSS. The two isolated footprints were located at -204bp and -167bp upstream, corresponding to the palindromic Motif#2 and the redundantly predicted MYB binding site, respectively. In the remaining footprints, additional predictions were found for an overlapping AGL15/CBF site, an auxin response element, overlapping GT1 and AGAMOUS sites, and one prediction for a TATA-less promoter. The latter may be related to the position of the only recognizable TATA box-like sequence, which at – 68bp upstream, which is more than double the usual 25-35bp described for other TATA-based promoters. In contrast, the 3’ enhancer region contained seventeen footprints arranged in roughly three clusters, spanning a region nearly 600 bp long. Two of these clusters closely corresponded with the previously noted clusters of predicted transcription factor sites, while the third was distinctly isolated and had no predicted transcription factors. Together, the footprints contained one of the three known WUS binding sites , two predicted AtHB1 binding sites, a cytokinin responsive element , several bZIP motifs, a KNOX-like site, and a predicted cis-motif forNPR1. Strikingly, the majority of the footprints also overlapped with a DNA transposable element in A. thaliana, At2TE50665 . It has previously been implied that WUS controls CLV3 expression in a concentration dependent manner, which is consistent with the close proximity of two demonstrated WUS binding sites .

The region around these two sites also contains several other TAAT cores within a single stretch about 100bp long, much of which is represented by four conserved footprints, which together might form a WUS binding site cluster. However, only the +970 WUS binding site was found to be perfectly conserved, while the other TAAT cores displayed mutations or were interrupted by indel sequences in one or more orthologs. Instead, when the region around the known WUS binding sites was examined in more detail with a 5bp sliding window, a strikingly periodic pattern was observed, where four different conserved motifs were found to be regularly spaced about 15 bp apart. In order from 5’-3’, these motifs were identified as CCGTTGGG, AGTAC, TTGTCAA, and TAATTAATGG , the latter two of which correspond to a predicted W-box motif, and the +970 WUS binding site. In addition, a perfectly conserved sequence was found just 25-36 bp downstream in all orthologs, which consisted almost entirely of tandem repeats containing ATG. The ATG repeats also overlapped with a predicted ALFIN-1 homeodomain/Opaque-2 binding site, suggesting that this sequence may actually represent a modified bZIP motif, or perhaps an atypical homeodomain binding site containing a TGAT core motif. It is not clear how many potential binding sites are present in these ATG repeats, but in consideration of the size of the conserved region, it seems likely that they could accommodate up to three transcription factor proteins simultaneously.The potential functional role of the TGAT motifs is further supported by the observation that they are 4x over-represented in the surrounding 124 bp conserved region, while the TAAT cores actually are 5x under-represented. In addition, pair-wise distance measurements between the two cores revealed a skewed distribution, where few sites were found closer together than the median value of 5bp. When several median-length pairs were aligned, this corresponded to the 13bp motif TAATnnWnnTGAT. When this motif was subjected to Patmatch searches of the A. thaliana genome, it was found to be 26x over represented among the genes directly targeted by WUS. Multiple copies of the 13bp motif were also found in several target genes, including two in the 3’ enhancer of AtCLV3.