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Campylobacter and pathogenic Escherichia coliillnesses have been attributed to the consumption of fresh produce. The leafy green, kale, is increasingly consumed raw. In comparison to other leafy greens, kale has a longer shelf-life. Due to the extended shelf-life of kale, it is warranted to examine the survival of pathogenic Campylobacter jejuni and E. coli O157:H7 inoculated on the surface of kale stored in a controlled environment at 4 ± 1.4°C, and average humidity of 95 ± 1.9% over a 23-day period. At predetermined time points (days 0, 1, 2, 3, 5, 7, 9, 11, 13, 15, 17, 19, and 21), inoculated kale was destructively sampled and the surviving bacteria determined by serial dilution and plating onto Tryptic soy agar, Charcoal cefoperozone deoxycholate agar, and Eosin methylene blue for total aerobic bacteria, C. jejuni, and E. coli O157:H7, respectively. Enrichment and PCR were used for detection when pathogens were not detected using serial dilution and plating. Aerobic heterotrophic bacteria increased over the 23-day period, in contrast, significant declines in the inoculated pathogens were observed. Inoculated E. coli O157:H7 survived longer on kale (up to 19 d); in comparison, C. jejuni was undetectable by day 13 using enrichment and PCR or plating. In conclusion, C. jejuni and E. coli O157:H7 declined on fresh kale over time when held at refrigerated temperatures but were still detected during the majority of the time when the kale would likely still be considered edible by consumers.

Though the existing literature does not provide evidence to suggest that genetically modified foods are worse for humans and the environment than organically grown foods, a general tone exists from the public expressing primarily distrust and negativity towards genetically modified organisms (GMOs), pesticides, and growth hormones. This can result in fear/distrust around food, damage to the agriculture industry, and misinformed nutrition advice, leading to further negative outcomes. The purpose of this project was to formally understand the consumer’s attitudes and perceived risk in relation to their knowledge about common agricultural practices, specifically genetic engineering of food. Additionally, the project aimed to identify if there is a correlation between the occurrence of disordered eating/dieting and knowledge, attitudes, and perceived risk of genetically modified organisms. One hundred thirty participants volunteered to take a survey which gathered basic demographic information, prevalence of dieting/disordered eating and eating disorder diagnosis, general knowledge of GMOs and their attitudes and perceived risk in relation to human health, nutrition, and environmental impact. The results provide trends of high self-confidence in knowledge about GMOs, moderate-to-low actual knowledge, neutral-to-negative overall attitudes, and moderate-to-high overall perceived risk. The trends suggest that increasing levels of inaccurate knowledge on the topic of GMOs correlate with increasing negative attitudes towards GMOs. Those diagnosed with an eating disorder reported the highest prevalence of fear of GMOS, followed by those who engaged in dieting or disordered eating. The evidence gives way to the idea that individuals who have a higher involvement in following diets or engaging in disordered eating behaviors are more likely to feel fearful of agriculture- and food-related practices. Based on the findings of this study, a call for improved education dissemination

Specialists on the Virginia Vegetable Team are committed to assisting growers, regardless of business size, with obtaining the freshest, highest quality, and most efficiently produced vegetables with the idea of safety and economic viability in mind. Please reach out to your local Cooperative Extension agent and/or vegetable team specialist to answer any vegetable related questions important to Virginia growers. Please click on the specialist’s name to be directed to their university’s webpage. The team routinely conducts applied research, presents information to growers and industry, publishes farmer friendly fact sheets, and works towards training Agriculture and Natural Resource (ANR) Extension agents and governmental employees through in-service trainings to ensure information is disseminated to the masses.

Outbreaks of Salmonellosis have been traced to contaminated tomato. The produce production environment poses a risk for Salmonella contamination; however, little is known about the effects of pest management practices on Salmonella during production. The study objective was to evaluate pesticide application on the inactivation of Salmonella on tomato leaves. Thirty greenhouse-grown tomato plants were inoculated with S. enterica serovars Newport or Typhimurium. Inoculation was performed by dipping tomato leaves in an 8-log CFU/mL Salmonella suspension with 0.025% (vol/vol) Silwet L-77 surfactant for 30 s, for a starting concentration of 6–7 log CFU/mL. Plants were treated with one of four pesticides, each with a different mode of action [acibenzolar- S-methyl, copper-hydroxide, peroxyacetic acid (PAA), and streptomycin]. Pesticides were applied at manufacturers' labeled rate for plant disease management with water as a control treatment. Salmonella was enumerated at 0.125 (3 h), 2, 6, and 9 days post-inoculation (dpi), and counts log-transformed. Growth of Salmonella was not observed. At 2 dpi, PAA and streptomycin significantly reduced surface Salmonella concentrations of inoculated tomato leaves (0.7 and 0.6-log CFU/g, respectively; p ≤ 0.05), while significant Salmonella log reduction occurred in the ground tomato leaves after copper hydroxide treatment (0.8-log CFU/g; p ≤ 0.05), compared to the control. No significant differences in Salmonella populations on tomato leaf surface and in ground leaves were observed from 2 to 9 dpi, regardless of pesticide application. These findings suggest single in-field pesticide applications may not be an effective mitigation strategy in limiting potential Salmonella contamination. Future research, including multiple in-field pesticide applications, or pesticide use in combination with other mitigation strategies, may offer intriguing management practices to limit possible preharvest contamination.

Surface water environments are inherently heterogenous, and little is known about variation in microbial water quality between locations. This study sought to understand how microbial water quality differs within and between Virginia ponds. Grab samples were collected twice per week from 30 sampling sites across nine Virginia ponds (n = 600). Samples (100 mL) were enumerated for total coliform (TC) and Escherichia coli (EC) levels, and physicochemical, weather, and environmental data were collected. Bayesian models of coregionalization were used to quantify the variance in TC and EC levels attributable to spatial (e.g., site, pond) versus nonspatial (e.g., date, pH) sources. Mixed-effects Bayesian regressions and conditional inference trees were used to characterize relationships between data and TC or EC levels. Analyses were performed separately for each pond with ≥3 sampling sites (5 intrapond) while one interpond model was developed using data from all sampling sites and all ponds. More variance in TC levels were attributable to spatial opposed to nonspatial sources for the interpond model (variance ratio [VR] = 1.55) while intrapond models were pond dependent (VR: 0.65–18.89). For EC levels, more variance was attributable to spatial sources in the interpond model (VR = 1.62), compared to all intrapond models (VR < 1.0) suggesting that more variance is attributable to nonspatial factors within individual ponds and spatial factors when multiple ponds are considered. Within each pond, TC and EC levels were spatially independent for sites 56–87 m apart, indicating that different sites within the same pond represent different water quality for risk management. Rainfall was positively and pH negatively associated with TC and EC levels in both inter- and intrapond models. For all other factors, the direction and strength of associations varied. Factors driving microbial dynamics in ponds appear to be pond-specific and differ depending on the spatial scale considered.

The heterogeneity of produce production environments complicates the development of universal strategies for managing preharvest produce safety risks. Understanding pathogen ecology in different produce-growing regions is important for developing targeted mitigation strategies. This study aimed to identify environmental and spatiotemporal factors associated with isolating Salmonella and Listeria from environmental samples collected from 10 Virginia produce farms. Soil (n = 400), drag swab (n = 400), and irrigation water (n = 120) samples were tested for Salmonella and Listeria, and results were confirmed by PCR. Salmonella serovar and Listeria species were identified by the Kauffmann-White-Le Minor scheme and partial sigB sequencing, respectively. Conditional forest analysis and Bayesian mixed models were used to characterize associations between environmental factors and the likelihood of isolating Salmonella, Listeria monocytogenes (LM), and other targets (e.g., Listeria spp. and Salmonella enterica serovar Newport). Surrogate trees were used to visualize hierarchical associations identified by the forest analyses. Salmonella and LM prevalence was 5.3% (49/920) and 2.3% (21/920), respectively. The likelihood of isolating Salmonella was highest in water samples collected from the Eastern Shore of Virginia with a dew point of >9.4°C. The likelihood of isolating LM was highest in water samples collected in winter from sites where <36% of the land use within 122 m was forest wetland cover. Conditional forest results were consistent with the mixed models, which also found that the likelihood of detecting Salmonella and LM differed between sample type, region, and season. These findings identified factors that increased the likelihood of isolating Salmonella- and LM-positive samples in produce production environments and support preharvest mitigation strategies on a regional scale. IMPORTANCE This study soug

The contamination of ready-to-eat produce with Listeria monocytogenes (LM) can often be traced back to environmental sources in processing facilities and packinghouses. To provide an improved understanding of Listeria sources and transmission in produce operations, we performed whole-genome sequencing (WGS) of LM (n = 169) and other Listeria spp. (n = 107) obtained from 13 produce packinghouses and three fresh-cut produce facilities. Overall, a low proportion of LM isolates (9/169) had inlA premature stop codons, and a large proportion (83/169) had either or both of the LIPI-3 or LIPI-4 operons, which have been associated with hypervirulence. The further analysis of the WGS data by operation showed a reisolation (at least 2 months apart) of highly related isolates (,10 hqSNP differences) in 7/16 operations. Two operations had highly related strains reisolated from samples that were collected at least 1 year apart. The identification of isolates collected during preproduction (i.e., following sanitation but before the start of production) that were highly related to isolates collected during production (i.e., after people or products have entered and begun moving through the operation) provided evidence that some strains were able to survive standard sanitation practices. The identification of closely related isolates (,20 hqSNPs differences) in different operations suggests that cross-contamination between facilities or introductions from common suppliers may also contribute to Listeria transmission. Overall, our data suggest that the majority of LM isolates collected from produce operations are fully virulent and that both persistence and reintroduction may lead to the repeat isolation of closely related Listeria in produce operations. IMPORTANCE Listeria monocytogenes is of particular concern to the produce industry due to its frequent presence in natural environments as well as its ability to survive in packinghouses and fresh-cut processing facilities over time.

Salmonella enterica contamination of low water activity foods (LWAFs) has resulted in recalls of spices, herbs, and seeds and outbreaks of salmonellosis. To improve the safety of these ready-to-eat products, new treatment methods, including fumigation with chlorine dioxide (ClO2) or hydrogen peroxide (H2O2) gas are being explored, and effectiveness determined. To prevent overestimation of treatment effectiveness, it is vital that recovery methods should accurately quantify all viable cells, even those injured. This study evaluated different media and supplements for the recovery of multiple strains of S. enterica and Enterococcus faecium NRRL B2354, from ClO2 or H2O2 treated black peppercorns, dried basil leaves, and chia seeds. Also, this study aimed to compare the log reduction of these two microorganisms to evaluate E. faecium NRRL B2354, as a surrogate for S. enterica. On average, recovery of S. enterica was improved by 1 log CFU from ClO2 and H2O2 treated LWAFs when a non-selective but differential media containing tryptic soy agar with yeast extract, ammonium iron citrate and sodium thiosulfate (MTSAYE) was used, when compared to plating on XLD (p < 0.05). Furthermore, addition of sodium pyruvate, ferrous sulfate, or 3’3’-thiodiproionate supplements to MTSAYE did not show increased recovery of either S. enterica or E. faecium NRRL B2354 (p > 0.05). On each treatment and LWAF combination tested, there was no significant difference between the log reduction of S. enterica

This copy of the 2022/2023 Mid-Atlantic Commercial Vegetable Production Recommendations replaces all previous editions of the Commercial Vegetable Production Recommendations published individually for Delaware, Maryland, New Jersey, Pennsylvania, Virginia, and West Virginia. Information presented in this publication is based on research results from the University of Delaware, the University of Maryland, Rutgers - The State University of New Jersey, The Pennsylvania State University, Virginia Polytechnic Institute and State University, West Virginia University, and the U.S. Department of Agriculture, combined with industry and grower knowledge and experience. This publication will be revised biennially. In January 2023, a Critical Update with important updates for this publication will be communicated through local Extension Agents and Vegetable Specialists. The editors welcome constructive criticism and suggestions from growers and industry personnel who may wish to help improve future editions of this publication. These recommendations are intended for the commercial vegetable grower who has to make numerous managerial decisions. Although the proper choices of variety, pesticides, equipment, irrigation, fertilizer, and cultural practices are the individual vegetable grower’s responsibility, it is intended that these recommendations will facilitate decision-making. Recommended planting dates will vary across the six-state region. Local weather conditions, grower experience, and variety may facilitate successful harvest on crops planted outside the planting dates listed in this guide. This can be evaluated in consultation with the local agents and state specialists. Government agencies and other organizations administrating crop insurance programs or other support programs should contact local Extension agents and/or vegetable specialists for guidance. Not to be used by home gardeners.

Fecal contamination of surface water has been associated with multiple enteric disease outbreaks and food recalls. Thus, it is important to understand factors associated with fecal contamination of agricultural water sources. Since fecal indicator bacteria (FIB) were used to monitor surface water for potential fecal contamination, the purpose of the present study was to characterize associations between environmental factors, and (i) FIB (E. coli, Enterococcus, and coliform) levels, and (ii) host-specific fecal marker detection. This study used data collected from 224 sites along 3 waterways, which spanned an urban-rural gradient around Syracuse, New York. Between 2008 and 2017, 2,816 water samples were collected, and E. coli, Enterococcus, and/or coliform concentrations were enumerated. Thirty-one samples were also tested for human and ruminant microbial source-tracking markers. Water quality (e.g., turbidity, nitrate) and weather data were also collected for each site. Univariable Bayesian regression was used to characterize the relationship between each microbial target and land use, water quality, and weather factor. For eachmodel, probability of direction and region of practical equivalence overlap (ROPE) were calculated to characterize the association’s direction and strength, respectively. While levels of different FIB were not correlated with each other, FIB levels were associated with environmental conditions. Specifically, FIB levels were also positively associated with temperature, nutrient and sediment levels. Log10 E. coli levels increased by 0.20 (CI = 0.11, 0.31) and log10 Enterococcus levels increased by 0.68 (CI=0.08, 1.24) for each log10 increase in salinity and nitrate, respectively. These findings may indicate that similar processes drove microbial, sediment, and nutrient contamination of the sampled watersheds. While fecal contamination was strongly associated with land use, the direction of association varied between FIBs and the buffer distanc

Fresh produce may be contaminated by bacterial pathogens, including Listeria monocytogenes, during harvesting, packaging, or transporting. A low-intensity cavitation process with air being injected into water was studied to determine the microbubbles’ efficiency when detaching L. monocytogenes from stainless steel and the surface of fresh cucumber and avocado. Stainless steel coupons (1″ × 2″), cucumber, and avocado surfaces were inoculated with L. monocytogenes (LCDC strain). After 1, 24 or 48 h, loosely attached cells were washed off, and inoculated areas were targeted by microbubbles (~0.1–0.5 mm dia.) through a bubble diffuser (1.0 L air/min) for 1, 2, 5, or 10 min. For steel, L. monocytogenes (48 h drying) detachment peaked at 2.95 mean log reduction after 10 min of microbubbles when compared to a no-bubble treatment. After 48 h pathogen drying, cucumbers treated for 10 min showed a 1.78 mean log reduction of L. monocytogenes. For avocados, L. monocytogenes (24 h drying) detachment peaked at 1.65 log reduction after 10 min of microbubbles. Microbubble applications may be an effective, economical, and environmentally friendly way to remove L. monocytogenes, and possibly other bacterial pathogens, from food contact surfaces and the surfaces of whole, intact fresh produce.

Food for thought, every year in the United States, foodborne illness accounts for notable losses of healthy life years. Given that food and water supplies are the basis for human survival, it seems likely that institutions of higher learning would be a logical place for a robust educational platform to be interjected. College students may not thrive securely as healthy, productive adults without foundational food safety skills and knowledge. Therefore, a short, interactive, engaging food safety curriculum was developed for college students working in Dining Services at Pensacola Christian College. The emphasis on collegiate dining services may exponentially mitigate the toll of foodborne illness as college campuses being one of the latter points of preparatory insertion of knowledge for building life skills and seeking advancement in education. The ultimate goal of this training is to provide a basis for food safety practices through strategic and cohesive training within the collegiate arena (in this case one university dining service team of 600-800 students).

The microbial quality of agricultural water is often assessed using fecal indicator bacteria (FIB) and physicochemical parameters. The presence, direction, and strength of associations between microbial and physicochemical parameters, and the presence of human pathogens in surface water vary across space (e.g., region) and time. This study was undertaken to understand these associations in two produce-growing regions in Florida, USA, and to examine the pathogen ecology in waterways used for produce production. The relationship between Salmonella presence, and microbial and physicochemical water quality; as well as weather and land use factors were evaluated. Water samples were collected from six sites in North Florida (N = 72 samples) and eight sites in South Florida (N = 96 samples) over 12 sampling months. Land use around each sampling site was characterized, and weather and water quality data were collected at each sampling. Salmonella, generic Escherichia coli, total coliform, and aerobic plate count bacteria populations were enumerated in each sample. Univariable and multivariable regression models were then developed to characterize associations between microbial water quality (i.e., E. coli levels and Salmonella presence), and water quality, weather, and land use factors separately for North and South Florida. The E. coli and total coliforms mean concentrations (log(10) MPN/100 mL) were 1.8 +/- 0.6 and >3.0 +/- 0.4 in North and 1.3 +/- 0.6 and >3.3 +/- 0.2 in South Florida waterways, respectively. While Salmonella was detected in 23.6% (17/72) of North Florida and 28.1% (27/96) of South Florida samples, the concentration ranged between <0.48 and 1.4 log(10) MPN/100 mL in North Florida, and E. coli levels, and if a sample was Salmonella-positive. The factors associated with Salmonella presence and log(10) E. coli levels in North Florida differed from those in South Florida; no factors retrained in multivariable regression models were the same for the North and