NITROGEN FIXATION OF DRY BEANS BRED FOR HILLSIDE AND MARGINALLAND PRODUCTION IN HONDURAS

摘要

Dry beans (Phaseolus vulgaris L.) have a beneficial nutritional profile and are an affordable source of protein making them a dietary staple in developing economies. Beans are an important crop in Honduras, however yields are low averaging 717 kg ha"1(Reyes et al, 2016). Seventy percent of Honduran farmers are subsistence, farming steep hillside plots (15-30°) with nutrient-poor soils, and with limited access to crop inputs including N fertilizers. Dry beans form symbiotic associations with Rhizobium spp. which convert atmospheric nitrogen into useable plant forms, a process termed symbiotic nitrogen fixation (SNF). The capacity for SNF could be exploited to ensure yields in production systems where alternative sources of N are not accessible. Inthe early 1990s, farmer participatory research was initiated with farmer groups (CIALs) who identified dry beans as a crop to improve through participatory plant breeding (PPB). In this study, we collaborated with the Fundacion para la Investigacion Participativa con Agricultores de Honduras (FIPAH), an NGO which works with a large group of CIALs on PPB. Our objectives were to evaluate a panel of bean genotypes for SNF capacity, to determine genetic relatedness among the panel, and to identify promisinggenotypes for use in breeding to enhance SNF performance.