Nitrogen fixation of dry beans bred for hillside and marginal land production in Honduras

Authors: WILKER, JENNIFER - University Of Guelph; HUMPHRIES, SALLY - University Of Guelph; ROSAS, JUAN - Zamorano, Panamerican School Of Agriculture; Porch, Timothy - Tim; GOMEZ, M - Foundation For Participatory Research With Honduran Farmers; PAULS, PETER - University Of Guelph

Submitted to: Bean Improvement Cooperative Annual Report
Publication Type: Research Notes
Publication Acceptance Date: 5/18/2020
Publication Date: 5/20/2020
Citation: Wilker, J., Humphries, S., Rosas, J.C., Porch, T.G., Gomez, M., Pauls, P. 2020. Nitrogen fixation of dry beans bred for hillside and marginal land production in Honduras. Bean Improvement Cooperative Annual Report. 63: 59-60.

Interpretive Summary: Dry beans 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. 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 Nitrogen 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 Nitrogen are not accessible. In the 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 Fundación para la Investigación 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 promising genotypes for use in breeding to enhance SNF performance.

Technical Abstract: 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. 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. In the 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 Fundación para la Investigación 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 promising genotypes for use in breeding to enhance SNF performance.