Nutrient Cycling in Organic Field Crops in Canada and the United States

• DOI: 10.2134/agronj2019.04.0275
• Publication Date: 2019-09-05T19:30:20Z
• Authors: Patrick M. Carr; Michel A. Cavigelli; Heather Darby; Kathleen Delate; Jed O. Eberly; Greta G. Gramig; Joseph R. Heckman; Ellen B. Mallory; Jennifer R. Reeve; Erin M. Silva; David H. Suchoff; Alex L. Woodley
• Keywords: Nutrient Management; Nutrient cycle; Crop Rotation

Organic farmers have identified soil fertility and weed management as the two highest research priority areas. No review exists of on nutrient in organic field crop systems. We conducted a comprehensive to identify principles factors governing management, knowledge gaps, future needs grain other systems Canada United States. compared results from different climates, soils, rotational sequences. Results indicate that (i) dual‐use cover/green manure crops and/or animal are most common sources plant available N nutrients systems; (ii) deficiencies can develop through sole reliance crops; (iii) dependence lead P excesses; (iv) conventional testing procedures may not accurately predict needs; (v) greater microbial processes cycling is needed; (vi) better understanding impact weeds create synergies. Knowledge gaps include lack how biomes influence nutrient‐use efficiency diversity rotations fertility, sustainability, resilience Likewise, interactions between weeds, crops, strategies poorly understood. Core Ideas Soil, climate, sources, land use strategies. Cover/green manures used maintain farms. Conventional be ideally suited Tracking temporal changes improve plans. More community structure/function production needed.