Location: New England Plant, Soil and Water Research Laboratory
2022 Annual Report
Accomplishments
1. Cover crop and soil amendment impacts on soil properties, yield, and disease development in organic vegetable production.. Sustainable organic vegetable farming faces many production challenges, including maintaining adequate soil health and fertility, management of weeds, pests, and diseases, and balancing multiple different vegetable crops. ARS researchers in Orono, Maine, evaluated the impacts of two different cover crop (CC) strategies, as well as compost, silicon (Si), and biocontrol (BC) soil amendments on soil chemical and biological properties, crop development and yield, and disease and pest issues in organic vegetable production, as represented by legume (green snap bean), cucurbit (green zucchini squash), and solanaceous (sweet pepper) vegetable crops, in a three-year field trial. A multi-species CC mixture (6 crops, including legumes, grasses, and brassicas) resulted in lower biomass and ground cover relative to winter rye CC, but had no effect on crop development or yield. Compost amendments increased yields of bean, zucchini, and peppers, as well as increased soil pH, organic matter, and nutrient contents relative to a fertilizer-only treatment. Additions of Si reduced powdery mildew on squash and leaf necrosis of beans, and BC also provided some reductions in foliar diseases. These results help define specific management practices to improve organic vegetable production and provide useful information and options for growers.
Review Publications
Larkin, R.P., Griffin, T.S., Honeycutt, C.W., Olanya, O.M., He, Z. 2021. Potato cropping system management strategy impacts soil physical, chemical, and biological properties over time. Soil and Tillage Research. https://doi.org/10.1016/j.still.2021.105148.
Larkin, R.P. 2021. Use of crop rotations, cover crops and green manures for disease suppression in potato cropping systems. Review Article. https://doi.org/10.15377/2409-9813.2021.08.12.
Curland, R.D., Mainello, A., Perry, K.L., Hao, J., Charkowski, A.O., Bull, C.T., McNally, R.R., Johnson, S.B., Rosenzweig, N., Secor, G.A., Larkin, R.P., Gugino, B.K., Ishimaru, C.A. 2021. Species of Dickeya and Pectobacterium isolated in 2015-2016 from potatoes with soft rot disease in Northeastern and North Central United States. Microorganisms. https://doi.org/10.3390/microorganisms9081733.
