ENHANCING BIOLOGICAL NITROGEN FIXATION (BNF) OF LEGUMINOUS CROPS GROWN ON DEGRADED SOILS IN UGANDA, RWANDA, AND TANZANIA
2011 Annual Report
1a.Objectives (from AD-416)
Characterize inheritance of biological nitrogen fixation in dry beans and develop germplasm with improved biological nitrogen fixation.
1b.Approach (from AD-416)
Optimze biological nitrogen fixation in dry beans through genetics and plant breeding. Identify lines with high BNF and cross with lines with low BNF to devlop breeding populations. Evaluate breeding and mapping populations for BNF response and populate with markers for QTL analysis.
Three field experiments were conducted in Washington in 2011. Supporting experiments were conducted in Iowa and Tanzania. One experiment looked at the performance of 36 dry bean genotypes under three treatments: low nitrogen, high nitrogen, and with rhizobium inoculation. Fifty genotypes from the Andean gene pool and obtained from the BeanCAP project funded by NIFA were tested under low and high nitrogen. There were 45 additional accessions from the South American core germplasm collection similarly screened for biological nitrogen fixation efficiency under low and high nitrogen treatments. Soil, nodule, and plant tissue samples were collected from most plots for nitrogen and ureide analysis and isolation of endemic rhizobium strains. This agreement supports Objective 1a of the in-house project, with the goal to identify, characterize, and tag genes/QTL conditioning traits of economic importance in edible legume production, specifically those affecting biological nitrogen fixation efficiency.
This project was monitored by frequent emails and phone calls with the collaborators, and person-to-person contact at workshops, field site visits, and travel to respective countries in East Africa.