Traits That Matter: Meeting Farmers Needs through Improved Cover Crop Performance.

Cover crops are important components of sustainable crop production because they are multi-functional tools that provide a breadth of services. The ecosystem services they provide include both nitrogen scavenging and fixation, reduced erosion, improved soil health, weed suppression, and the provision of habitat and resources for beneficial organisms such as pollinators. When optimized, these services that cover crops provide can help address critical challenges to agricultural productivity including: adaptation to and mitigation against climate change; preservation of no-till agriculture in the face of multiple-herbicide resistant weeds; and minimize nutrient loading into our water supply.  However, the performance of legume cover crops can be quite variable; the variability in cover crop performance is largely a function of management constraints and poor performing germplasm.  Unlike cash crops, cover crops have not been bred to optimize the traits that farmers need, particularly on a regional basis. This deficiency means that modest investments in germplasm improvement could yield large benefits. In the case of legume cover crops, a national survey of farmers identified nitrogen fixation, winter hardiness, biomass production, and early vigor as the top four legume cover crop traits that need improvement through traditional and participatory breeding. As a result, we have assembled a multi-disciplinary team of scientists from government agencies (ARS, PMC, NPGS), universities, private sector companies, non-profit organizations, and farmers to breed new varieties of hairy vetch (Vicia villosa), Austrian winter pea (Pisum sativum), and crimson clover (Trifolium incarnatum) through traditional, participatory, and marker-assisted methods.