Project Number: 2090-21000-034-017-I
Project Type: Interagency Reimbursable Agreement
Start Date: Oct 1, 2018
End Date: Aug 31, 2022
Organic farmers use legume cover crops to provide nitrogen to subsequent crops and other important ecosystem services. Legume cover crops can help farmers reduce soil erosion, improve soil health, and avoid excessive applications of phosphorus from manure or compost. Despite the array of benefits that legume cover crops provide to organic farmers, legume cover crop breeding and cultivar development research has been extremely limited. Due to a lack of germplasm development efforts, most farmers use unimproved varieties or seed that is not adapted to their farm or region. Moreover, winter legume cover crops suffer late maturity, seed dormancy, winterkill, and indeterminate flowering. The objective of this project is to develop improved cultivars of legume cover crops for organic farming and a network for distributing seed of these improved cultivars to growers.
Legume cover crop germplasm, segregating populations, breeding lines, and varieties will be evaluated across multiple locations throughout the U.S. for improved performance and targeted agronomic characteristics of special interest to organic farmers, including stand establishment and vigor, disease resistance and forage yield. Seed of segregating populations will be provided to organic growers for testing and selection. Seeds from selected lines/plants will be increased in a counter season nursery and evaluated for potential use as a cover crop based on several traits including leaf type, internode length, and biomass production. Seed produced in counter-season nurseries will be treated, packaged, and sent to collaborating organic growers for subsequent evaluation in replicated yield trials.