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Sweetpotatoes are a major crop in California, ranking sixth in value among organic commodities in the state. In recent years, there has been growing consumer interest in diverse specialty varieties, particularly purple types and those associated with Asian American and Pacific Islander (AAPI) communities, some of which are currently imported into the state. In this study, we screened 45 diverse sweetpotato varieties and breeding lines under California organic conditions in a preliminary characterization of their agronomic performance. We then conducted culinary evaluations with a tasting panel of students primarily identifying as Asian/Asian American to determine the preference for each type in terms of flavor and culinary appeal. Our results indicated that major tradeoffs exist among existing germplasm, with no variety or line excelling across all agronomic and culinary traits. These results suggest that sweetpotato breeding could be an effective mechanism to combine superior agronomic traits of major commercial classes with the high culinary quality of diverse materials that are not adapted to California organic production. These results provide a strong justification for the value of sweetpotato breeding to ultimately promote a more profitable, sustainable, and just food system in the region. [ABSTRACT FROM AUTHOR]

Simple Summary: In 2019, California accounted for approximately 40% of organic products in the US, and dairy products and milk were the top organic commodity in the state. The objective of this study was to describe organic dairy cattle farmers' management practices and perceptions of diseases in California. A questionnaire on farm history and demographics, animal diseases, parasite problems, housing and pasture management, and organic education, was mailed to 160 organic dairy farms, of which 36 responded. Respondents were more likely to report mastitis in cows, pinkeye in heifers, and digestive problems in calves, as issues affecting their stock "often" or "almost always" in the last 12 months. Although most farmers vaccinated their cattle against Bovine Viral Diarrhea and Escherichia coli mastitis, they still described that these diseases frequently impacted their animals. Over half of the farmers did not perceive gastrointestinal parasites or biting flies to be a problem and did not observe signs of lice and mites. According to the results, the management of disease in all age classes is a concern; options and efficacies of alternative therapeutic methods, as well as preventive measures for organic dairies need to be further explored. In 2019, California accounted for approximately 40% of organic products in the US, and dairy products and milk were the top organic commodity in the state. The objective of this study was to describe organic dairy cattle farmers' management practices and perceptions of diseases in California. A survey inquiring about farm history and demographics, animal diseases, parasite problems, housing and pasture management, and organic education, was mailed to 160 organic dairy farms, of which 36 (22.5%) responded. Among respondents, the majority (83.9%) were located in Northern California; median farm size was 310 cows, and the dominant breed was Holstein (60.0%). Respondents were more likely to report mastitis in cows (45.2%), pinkeye in heifers (31.3%), and digestive problems in calves (47.0%), as issues affecting their stock "often" or "almost always" in the last 12 months. Although most farmers vaccinated their cattle against Bovine Viral Diarrhea (86.1%) and Escherichia coli mastitis (80.6%), they still described that these diseases frequently impacted their animals. Over half of the farmers did not perceive gastrointestinal parasites or biting flies to be a problem and did not observe signs of lice and mites. According to the results, the management of disease in all age classes is a concern; options and efficacies of alternative therapeutic methods, as well as preventive measures for organic dairies need to be further explored. [ABSTRACT FROM AUTHOR]

Background: For the successful adoption of organic farming especially under protected cultivation conditions there is a dire need to enrich and fortify the different composts for meeting out the requirements of crops. Experiments were conducted at Model Organic Farm, Department of Organic Agriculture and Natural Farming, CSKHPKV, Palampur and at farmers field in Akrot, Una and Rajol Kangra of HP with an objective to evaluate different enriched composts under protected organic farming conditions. Methods: The experiments were conducted with 9 treatments viz. Matka khad (M) + Rock phosphate (RP), Matka khad + Gypsum (G), Matka khad + Patent kali (PK), Matka khad + Lime (L), Matka khad + control, Matka khad + Combination of RP,G,PK,L + Tricoderma + Rhi/Azoto + PSB, Panchgavya + Combination of RP,G,PK,L + Tricoderma + Rhi/Azoto + PSB, Jeevamrit + Combination of RP,G,PK,L + Tricoderma + Rhi/Azoto + PSB and Vermicompost. These treatments were selected after preparation of enriched and fortified FYM and its evaluation by microbial and nutrient analysis. Pea crop variety Pb-89 and Capsicum crop variety California wonder were selected for the experiments under polyhouse at research farm and at farmer's field. Result: Results showed that inoculation of biomass with matka khad along with additives i.e. rock phosphate, gypsum, patent kali and lime @ of 1% and fortification with Tricoderma, suitable biofertilizer (Rhizobium/Azotobacter) along with PSB increased the yield of Pea crop more than 40% at organic farm and farmers fields, whereas in case of capsicum the increase in yield was to the tune of 14% at model organic farm and more than 40% at two different sites of farmers field. [ABSTRACT FROM AUTHOR]

This research examines the role of government mandated marketing programs in promoting certified organic produce in California. Data were gathered from public documents, interviews, focus groups, and an industry-wide survey. We find that most California mandated marketing programs minimally address organic production. Regarding the value of generic promotion, slightly more than one-third of the survey respondents indicated that they believed that their mandated marketing program's promotion efforts increased the sales of their organic products. Two options were highly ranked as alternatives to promote organic products, setting aside a representative amount of the marketing program's funds for the promotion of organic produce and establishing a non-governmental producer association to promote all organic produce. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing Escherichia coli O157: H7 has been implicated in many foodborne illnesses. In this study, survival of E. coli O157: H7 in 32 soils from California ( CA) and Arizona ( AZ) was investigated. Our goal was to correlate the survival time of E. coli O157: H7 in soils with 16S r RNA pyrosequencing based bacterial community composition. Kohonen self-organizing map of survival and associated soil chemical, physical and biological variables using artificial neural network analysis showed that survival of E. coli O157: H7 in soils was negatively correlated with salinity ( EC), but positively correlated with total nitrogen ( TN) and water soluble organic carbon ( WSOC). Bacterial diversity as determined by the Shannon diversity index had no significant ( P = 0.635) effect on ttd, but individual bacterial phyla had different effects. The survival of E. coli O157: H7 was positively correlated with the abundances of Actinobacteria ( P < 0.001) and Acidobacteria ( P < 0.05), and negatively correlated with those of Proteobacteria and Bacteroidetes ( P < 0.05). Our data showed that specific groups of bacteria correlate with the persistence of E. coli O157: H7 in soils thus opening new ways to study the influence of certain bacterial phyla on persistence of this pathogen and other related pathogens in complex environments. [ABSTRACT FROM AUTHOR]

This article compares the pest management practices of organic and conventional citrus growers in California, using a 2010 survey of growers. The survey results indicate that, on average, organic growers make less use of biological and cultural controls than conventional growers. This result is surprising because organic growers often rely heavily on these types of controls due to organic restrictions on chemical control. For some organic growers, a lack of farming experience, the smaller scale of their operations, and less financial reliance on citrus production may explain these results. [ABSTRACT FROM PUBLISHER]

Abstract: In California, USA, agricultural fumigant use regulations hinder the complete transition from methyl bromide (MB) to alternative fumigants. Alternative fumigants such as 1,3-dichloropropene (1,3-D) and chloropicrin (Pic) are being used on approximately half of California conventional strawberry production fields. Geographic use limits and buffer zones set by the California Department of Pesticide Regulation for 1,3-D + Pic restrict a more complete replacement of MB. Due to the regulatory constraints and public resistance to fumigant use, it is necessary to develop fumigant-free strawberry production systems. Trials were conducted during the 2007/2008 and 2008/2009 strawberry growing seasons at Salinas and Watsonville, California. Non-fumigant treatments including steam, mustard seed meal (MSM), Muscodor albus, and furfural, fertilizers including Mustard Products & Technologies fertilizer and stabilised urea, and fungicide treatments including AG3(NP), fludioxonil + mefenoxam (mfx), and mfx + thiophanate-methyl were evaluated for weed control and strawberry fruit yield, and compared to MB + Pic (MBPic) standard soil fumigation and an untreated control. Steam treatment applied pre-plant to achieve soil temperature of ≥70 °C for 20 min up to 25 cm soil depth consistently provided weed control similar to the MBPic standard soil fumigation. Use of oxyfluorfen herbicide prior to fungicide applications in 2008/2009 also controlled weeds similar to the MBPic standard soil fumigation. Strawberry yields in steam-treated plots with the exception of steam alone in 2007/2008 at Salinas, were comparable to MBPic. At Watsonville in 2008/2009, treatment effect on strawberry yields was insignificant. Yields in furfural and MSM treatments were comparable to MBPic only in some years or sites. With the exception of steam, none of the treatments can be considered viable replacement to MB. [ABSTRACT FROM AUTHOR]

Californians recently passed Proposition 2, barring the use of cages in egg production in the state. Because most consumers are unknowledgeable of egg production practices, the appearance of Proposition 2 likely served as an information shock that potentially affected consumer demand. In this paper, we use scanner data to investigate the market effects of Proposition 2 by studying whether and how consumer demand for eggs changed in the months leading up to the vote in San Francisco and Oakland. Results indicate that demand for the types of eggs associated with higher animal welfare standards, cage free and organic, increased over time and in response to articles on the proposition whereas demand for other types of eggs fell. These results coupled with the finding that cage free and organic egg demand was virtually unchanged in a location unaffected by the vote, Dallas, suggests that Proposition 2 had a significant effect on consumer preferences for eggs – increasing demand for cage free and organic eggs by 180% and 20%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Soil food webs cycle nutrients and regulate parasites and pathogens, services essential for both agricultural productivity and ecosystem health. Nematodes provide useful indicators of soil food web dynamics. This study was conducted to determine if nematode soil food web indicators and crop yield can be enhanced by combinations of cover crops in a conservation tillage system. The effects of three cover crop treatments (vetch/pea, oat/wheat and oat/wheat/pea/vetch) with low, medium and high C:N and a bare fallow control were investigated in Davis, CA. Nematode fauna, soil properties and plant productivity were measured. Soil food web indices, including the Enrichment Index (EI), Structure Index (SI), Basal Index (BI), and Channel Index (CI), based on the composition of nematode assemblages, were calculated to infer soil food web condition. Cover cropped tomato/corn rotations had twice the number of enrichment opportunist bacterial feeding nematodes, active participants in nitrogen mineralization, than fallowed tomato/corn rotations (opportunist bacterial feeders=163 versus 98). In winter fallowed plots food webs were basal, common in disturbed, nutrient-poor conditions (BI=37). Total number of enrichment opportunist nematodes, soil NH4-N levels, and inferred nitrogen mineralization, were higher in cover crop treatments with low to mid C:N ratios. Omnivore and predator nematodes were scarce, averaging less than 6 nematodes 100g−1 in all treatments. In year one, plant productivity was highest after fallow. In contrast, in year two productivity was highest after cover crops with high nitrogen content and productivity significantly correlated with the structure of the soil fauna. Monitoring the abundance of enrichment opportunists may provide managers with a new tool to evaluate soil food web nitrogen mineralization and plant productivity. [Copyright &y& Elsevier]

Abstract: Studying the management strategies suited to large-scale organic production, particularly during the mandated 3-year transition period from conventional management, is a unique research challenge. Organic production traditionally relies on small, diverse plantings and complex management responses to cope with soil fertility and pest pressures, so research should represent decision-making options of an organic grower at the farm scale. This study analyzes crop, soil, pest and management changes during the organic transition period on two ranches (40 and 47ha) in the Salinas Valley, California in cooperation with a large conventional vegetable producer, Tanimura and Antle, Inc. Permanent transects were established across the two ranches at the onset of adoption of organic practices, and soil and plants were sampled at harvest of almost all crops, while all management operations were recorded by the co-operator. The ∼10ha blocks were divided into many small plantings, and 17 different cash crop and cover crop species were planted during the transition period. Management inputs consisted of a range of organic fertilizers and amendments, sprinkler and drip irrigation, cultivation and hand-hoeing, and several types of organic pesticides. Results from the 3-year period followed these general trends: increase in soil biological indicators (microbial biomass and arbuscular mycorrhizae), low soil nitrate pools, adequate crop nutrients, minor disease and weed problems, and sporadic mild insect damage. Multivariate statistical analyses indicated that some crops and cultivars consistently produced higher yields than others, relative to the maximum yield for a given crop. Multi-factor contingency tables showed clear differences in insect and disease damage between crop taxa. Although Tanimura and Antle, Inc. used some of the principles of organic farming (e.g., crop diversity, crop rotation, and organic matter (OM) management), they also relied on substitution-based management, such as fertigation with soluble nutrients, initially heavy applications of organic pesticides, and use of inputs derived from off-farm sources. Their initial production of a large number of crop taxa in small plantings at staggered intervals proved to be an effective strategy for avoiding risks from low yields or crop failure and allowed them to move towards a smaller number of select, successful crops towards the end of the transition. This study demonstrates the feasibility of large-scale producers to transition to organic practices in a manner that was conducive to both production goals and environmental quality, i.e., increased soil C pools, low soil nitrate, and absence of synthetic pesticides. [Copyright &y& Elsevier]

Producers are interested in developing labelling schemes that go ‘beyond organic’ to address ethical criteria not included the US Department of Agriculture organic standards. However, consumer interests in labels that are not as widely available as organic in the market are poorly understood. This study reports results of focus-group research and a survey of 1000 households in the Central Coast region of California to determine which standards consumers are most interested in supporting through their purchases. The results indicate that standards for the humane treatment of animals have the highest level of support, followed by a standard for local origin, and for a living wage for workers involved in producing food. Logistic regression analysis suggests that humane is more likely to be chosen by women, European-Americans, younger people and frequent organic purchasers. Locally grown was preferred by older people and households with children. A living wage for workers involved in food production was selected more often by Latinos. Although a characterization of trends is not possible due to a cross-sectional design, the results suggest some potential directions for producers in this region who are willing to supply unmet consumer demands for ethical criteria. There are three basic directions that new and emerging labels may take with respect to US national organic standards: (1) separate from organic; (2) institutionally separate, but tightly integrated with organic; and (3) intended to supplant organic. The success of each of these strategies will depend on how much trust consumers continue to place in government oversight of organic food. The study results also suggest that the movement for a more sustainable food system would benefit from devoting more attention to issues of animal rights and social justice. [ABSTRACT FROM AUTHOR]

Abstract: The chemical composition of atmospheric particulate matter was measured at two sites near Los Angeles, California, over 3 weeks in July 2001, as part of the Gasoline/Diesel PM Split Study. Samples were composited for organic speciation analysis by day of week at each site to investigate weekly trends in chemical composition of the carbonaceous fraction of particulate matter. Observed weekly trends in elemental carbon (EC), hopanes, steranes, and polynuclear aromatic hydrocarbons (PAHs) indicate increased impacts of motor vehicle traffic on carbonaceous particulate matter concentrations on weekdays relative to weekends. Ambient average EC was approximately 4 times higher in the Friday samples than in Sunday samples at each site. Levoglucosan, a tracer species for biomass burning, and cholesterol, monopalmitin, and monostearin, tracers for food cooking operations, were all highest on Friday and lowest on Sunday. Late-week increases in aliphatic and aromatic diacids present in the particulate phase were also observed. Diacids in particulate matter have been seen to be indicators of secondary organic aerosol formation, and the day-of-week trend observed may be due to weekday increases in volatile precursor species present in the atmosphere. [Copyright &y& Elsevier]

• Hydrocarbon-bearing and aqueous fluids coexisted during formation of the McLaughlin deposit. • Carbonaceous material forms an important reservoir for Au at McLaughlin. • It is likely that hydrocarbon-bearing fluids transported metals at McLaughlin. • The role of hydrocarbons in ore-formation may be underestimated. Carbonaceous material (CM)-enriched silica is co-located with gold (Au) mineralization at the Au–Hg McLaughlin deposit, Geysers/Clear Lake area, California, U.S.A. The co-location suggests that hydrocarbons (HC) may be involved in mineralization and metal concentration processes, but little is known about the role of HC in the formation of ore deposits. Previous studies noted liquid oil inclusions in samples from the McLaughlin deposit, and proposed that the HC were liquid at the time of ore deposition. Hydrocarbon materials in the McLaughlin deposit occur as solid and liquid. Textural evidence suggests that hydrocarbon-rich and aqueous, silica-rich fluids were present simultaneously, as well as separately in alternating pulses. Synchrotron X-ray fluorescence microscopy of microscopic silica-free carbonaceous material reveals that the CM contains abundant ore metals e.g., Au, Ag, Hg, and Pb. The CM could have become metal-enriched by scavenging metals from other ore fluids, or it could have transported metals when the CM was still liquid, with subsequent in-situ degradation due to hydrothermal heat. Gold concentrations of up to 18 ppm were measured via acid digestion of solid and liquid HC material and subsequent inductively coupled plasma–mass spectrometry (ICP–MS) analyses. Hydrocarbon material with liquid to medium viscous properties bearing 10.8 ppm Au provides evidence that Au in liquid HC in the McLaughlin Au-Hg deposit is still mobile and that remobilization and/or transport of metals to the deposit by HC liquids cannot be ruled out. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing E. coli O157:H7 and non-O157 have been implicated in many foodborne illnesses caused by the consumption of contaminated fresh produce. However, data on their persistence in soils are limited due to the complexity in datasets generated from different environmental variables and bacterial taxa. There is a continuing need to distinguish the various environmental variables and different bacterial groups to understand the relationships among these factors and the pathogen survival. Using an approach called Topological Data Analysis (TDA); we reconstructed the relationship structure of E. coli O157 and non-O157 survival in 32 soils (16 organic and 16 conventionally managed soils) from California (CA) and Arizona (AZ) with a multi-resolution output. In our study, we took a community approach based on total soil microbiome to study community level survival and examining the network of the community as a whole and the relationship between its topology and biological processes. TDA produces a geometric representation of complex data sets. Network analysis showed that Shiga toxin negative strain E. coli O157:H7 4554 survived significantly longer in comparison to E. coli O157:H7 EDL 933, while the survival time of E. coli O157:NM was comparable to that of E. coli O157:H7 EDL 933 in all of the tested soils. Two non-O157 strains, E. coli O26:H11 and E. coli O103:H2 survived much longer than E. coli O91:H21 and the three strains of E. coli O157. We show that there are complex interactions between E. coli strain survival, microbial community structures, and soil parameters.

In July 2010, a horse from a rural farm (Farm A) in coastal Northern California was diagnosed with Salmonella Oranienburg infection following referral to a veterinary hospital for colic surgery. Environmental sampling to identify potential sources and persistence of Salmonella on the farm was conducted from August 2010 to March 2011. Salmonella was cultured using standard enrichment and selective plating. Pure colonies were confirmed by biochemical analysis, serotyped and compared by pulsed-field gel electrophoresis (PFGE) analysis. A total of 204 clinical and environmental samples at Farm A were analysed, and Salmonella spp. was isolated from six of eight (75%) horses, an asymptomatic pet dog, two of seven (28.6%) water samples from horse troughs, nine of 20 (45%) manure storage pile composites, 16 of 71 (22.5%) wild turkey faeces and four of 39 (10.3%) soil samples from the family's edible home garden. Well water and garden vegetable samples and horse faecal samples from a neighbouring ranch were negative. S. Oranienburg with a PFGE pattern indistinguishable from the horse clinical strain was found in all positive sample types on Farm A. The investigation illustrates the potential for widespread dissemination of Salmonella in a farm environment following equine infections. We speculate that a recent surge in the wild turkey population on the property could have introduced S. Oranienburg into the herd, although we cannot rule out the possibility wild turkeys were exposed on the farm or to other potential sources of Salmonella. Findings from the investigation indicated that raw horse manure applied as fertilizer was the most likely source of garden soil contamination. Viable S. Oranienburg persisted in garden soil for an estimated 210 days, which exceeds the 120-day standard between application and harvest currently required by the National Organic Program. The study underscores the need to educate the public about potential food safety hazards associated with using raw animal manure to fertilize edible home gardens., (© 2013 Blackwell Verlag GmbH.)