Page Banner

United States Department of Agriculture

Agricultural Research Service

Related Topics

Research Project: BIOLOGICAL NITROGEN FIXATION OF LEGUMINOUS CROPS GROWN ON DEGRADED SOILS IN UGANDA, RWANDA, AND TANZANIA

Location: Sugarbeet and Bean Research

Project Number: 3635-21430-009-06
Project Type: Reimbursable

Start Date: Jan 01, 2010
End Date: Sep 30, 2012

Objective:
To identify, study, and develop common bean germplasm with improved nitrogen fixation potential for use in Rwanda, Uganda, and Tanzania. To examine the relationship between nitrogen fixation and seed quality, including seed sugars and antioxidant levels.

Approach:
Germplasm Screen: Common bean germplasm will be screened in 2 field sites in Rwanda under high and soil N levels and+/- Rhizobium inoculums. Superior N fixers will be identified via measurement of seed N levels in combination with nodule number and nitrogenase activity (acetylene reduction). Germplasm will be locally adapted and will be of the two important growth habit types for the region, determinate bush and climbing bean. Germplasm will also be screened in US using same methods, but adapted to U.S. and with type II and type III growth habits. Seed antioxidant activity and total flavonoids for all lines will be measured. Molecular mapping: A preexisting common bean RIL populations will be identified to use to map traits related to BNF. The population will be planted in MI for 2 years in two environments: low soil N and high soil N. Traits to be measured include seed total N, plant N, nodule number, nodule nitrogenase activity, seed antioxidant and total flavonoids. SSR markers will be added to the RIL population if necessary. QTL analysis will be conducted with phenotypic and molecular data.

Last Modified: 9/21/2014
Footer Content Back to Top of Page