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Sustainable pest management requires growers and regional land managers to consider the relationships among pest management practices, pest and natural enemy communities, crop loss, and multi-scalar habitat complexity. However, the causal links among these variables, in particular potential interactions between landscape and local-scale habitat complexity, remain underexplored. In the context of organically managed strawberry crops in California’s Central Coast, we tested the independent effects of landscape and local habitat complexity gradients on arthropod communities and crop loss using a piecewise structural equation model (PSEM). We found that landscape-scale woody habitat proportion indirectly decreased crop loss through its positive effect on natural enemy abundance, while grassland proportion had the opposite effect due to its association with an important strawberry pest (Lygus spp.). We detected a pattern suggesting that on-farm diversification practices are most effective at reducing crop loss at an intermediate level (26%) of woody habitat proportion. Both organic-compliant insecticide application and tractor vacuuming negatively impacted natural enemies, and therefore had qualified effects on crop loss. Our study shows the key roles of native woodlands and natural enemy communities in reducing crop loss and highlights the importance of managing habitat complexity at both landscape and local scales.

Organic cucurbit growers face many challenges to production including insect pests, insect-vectored diseases, and non-vectored diseases. While Organic Material Review Institute (OMRI) -listed pesticides underperform at suppressing pests and diseases, some alternative pest management strategies hold promise, but little research exists on their cost-effectiveness. We compared the efficacy of mesotunnel systems (nylon-mesh netting row covers deployed over bent metal hoops) and OMRI-listed pesticides (fungicides and insecticides) on acorn squash across 2 years. During the early part of the season, before row covers were removed for pollination, we found 1.7 (2020) and 0.3 (2021) times more cucumber beetles in the uncovered plots compared to the mesotunnels. Powdery mildew incidence was 36 and 25% lower under the mesotunnels compared to the uncovered plots in 2020 and 2021, respectively. Marketable yield of acorn squash was 46–54% higher in the mesotunnels compared to the uncovered treatments. OMRI-listed pesticide treatments reduced powdery mildew incidence compared to untreated control treatments. However, for pest presence, OMRI-listed pesticide treatments did not differ from untreated control treatments in either year, nor did it differ in marketable yield in 2020. Finally, the mesotunnel-only system was 47% more profitable compared to the OMRI-listed pesticide treatment and 47% more profitable compared to the uncovered plots. These results highlight mesotunnels as an economically viable pest management strategy for organic cucurbit growers in the U.S.

Harlequin bug (Murgantia histrionica) poses a significant threat to cruciferous vegetable crops, leading to economic losses and challenges in sustainable agriculture. This 2-year field study evaluated the efficacy of exclusion netting and selected biopesticides in controlling harlequin bug populations in a field-grown broccoli crop. Treatments included an untreated control, industry standards Azera and Entrust, and ProtekNet mesh netting. Additionally, three commercial essential oil treatments including Essentria IC-3, Nature-Cide, and Zero Tolerance were tested along with two bokashi fermented composting products BrewKashi and Oriental Herbal Nutrient (OHN). During both the first and second year of the study, none of the commercially produced essential oil products or bokashi products were effective in controlling harlequin bug or preventing leaf scars. Conversely, ProtekNet consistently provided the highest level of protection against harlequin bugs of all stages as well as leaf damage scars; it also provided the largest broccoli head width and highest yield. Entrust showed similar results compared to ProtekNet, both with the control of harlequin bug life stages and with leaf scars. These findings indicate that both ProtekNet and Entrust are effective organic alternatives for managing harlequin bug on broccoli, while the selected essential oil and bokashi products do not appear to be effective.

Aims. To investigate the healing process and nickel release of the Hyperion occluder (Comed BV, Netherlands), as compared to the Amplatzer septal occluder (ASO) (St. Jude Medical Inc., St. Paul, MN, USA) in a chronic swine model. Background. Some long-term complications occurring after percutaneous atrial septal defect (ASD) closure may be partially associated with an inappropriate healing of the device and increased nickel release. There is no direct comparative study of different occluders for healing and nickel release. Methods. After percutaneous ASD creation, 12 pigs were implanted with 15 mm Hyperion (n = 6) and 15 mm ASO (n = 6) devices. After 1 month (n = 3 for each device) and 3 months (n = 3 for each device) of follow-up, device explantation was performed and healing was assessed using histopathological workup. Systemic and tissular nickel release was performed. Results. Implantation was successful in 100% without complications. Device coverage was observed as early as 1 month after implantation and was almost complete after 3 months. A granulation tissue with a predominantly mononuclear inflammatory reaction was observed in contact with nitinol wires while an inflammatory reaction was seen in contact with textile fibers. We found no statistically significant difference between the 2 devices whether for histological grading scores or systemic nickel release, regardless to follow-up duration. Conclusions. In this preclinical study, we demonstrated that Amplatzer septal occluder and Hyperion occluder were not significantly different for device healing and nickel release processes.

California's Central Coast rose to national food safety prominence following a deadly 2006 outbreak of Escherichia coli O157:H7 that was traced to spinach grown in this intensive agricultural region. Since then, private food safety protocols and subsequent public regulations targeting farm-level practices have developed extensively, aiming to avert future foodborne illness crises. However, amidst sweeping reforms in prescribed best practices for food safety, growers were pressured to take precautionary approaches to control pathogenic contamination—suppressing wildlife near fields, removing habitat, restricting biological soil amendments (e.g., compost, manure), and most recently, chemically treating irrigation water—that may generate negative unintended consequences for environmental and social sustainability. We synthesize socio-ecological data from three qualitative, interview-based studies to examine grower perceptions and experiences of food safety reforms in California's Central Coast region and explore the effects of food safety regulations on environmental and socio-economic sustainability. We identify three disjunctures between food safety requirements and farming realities in practice: (1) Growers perceive that some food safety practices legitimately mitigate risk, while others fail to reduce or even accentuate risk; (2) Food safety requirements can create contradictions in the co-management of food safety and environmental sustainability; and (3) Food safety requirements may foster impediments to regional food systems socioeconomic sustainability. We argue that these disjunctures warrant changes in food safety policy, implementation, and/or food safety education. We provide concrete suggestions for shifting the focus of food safety reform away from the narrow surveillance of individual grower compliance and toward an integrated perspective on regional risk, vulnerability, and resilience.

Brassicaceous leafy greens are an important crop for small growers but are difficult to produce due to damage by flea beetles. Flea beetles are problematic for growers as they chew many small holes through leaves rendering produce unmarketable. We tested the efficacy of several essential oils, the woven-mesh row cover ProtekNet, and the spunbonded row cover Agribon, compared to organic and conventional insecticides and no spray controls in the spring and fall of 2019. We found that the two row cover treatments (Agribon and ProtekNet) provided the best control of flea beetles and associated damage. Thyme oil was highly phytotoxic and killed the crop entirely and rosemary and neem essential oils caused mild phytotoxic burns. Organic insecticides rarely performed better than the no spray control. While conventional insecticides controlled most flea beetles, the crop was often still too highly damaged to sell. The results of our study suggest row covers offer producers an effective method of flea beetle control that reduces their dependence on insecticides for conventional and organic production.

Fine-mesh exclusion netting is a potential alternative to organic and conventional insecticide application to control numerous pests of fruit crops. We tested whether fine-mesh exclusion netting would reduce pest abundance and increase marketable yield compared to organic spinosad insecticide sprays in an organically managed blackberry field. At the completion of flowering, we covered blackberry rows with fine-mesh exclusion netting (ProtekNet) and treated alternating rows with an organic spinosad insecticide (Entrust™). Fine-mesh exclusion reduced green June beetle (Cotinus nitida Linnaeus) and bird presence and marginally reduced Japanese beetle (Popillia japonica Newman) presence on blackberry canes compared to organic spinosad insecticide treatment. Exclusion netting reduced the capture of spotted-wing Drosophila (Drosophila suzukii Matsumara; “SWD”) in baited traps in the fourth week of exclusion and reduced the overall number of SWD adults emerging from harvested blackberry fruits. Marketable yield in the fine-mesh exclusion treatments was two times higher than the organic spinosad insecticide treatment. These results suggest that fine-mesh exclusion netting is a functional pest control alternative to insecticide treatment for organic blackberry production.