NitroGENES

Developing Country Collaboration with the International Institute for Tropical Agriculture (IITA)

Maize is a major cereal crop in West and Central Africa, accounting for more than 20% of domestic food production. Not only has maize replaced sorghum and millet as food staples, but it is fast becoming an important source of cash for smallholder farmers (Smith et al., 1997). The low N content in soils of the Western and Central African savannas, coupled with the high costs of N fertilizer, often make N the limiting nutrient for maize production. As a result, N-deficiency is common in the maize crop produced in this geographical region.

The International Institute for Tropical Agriculture (IITA), based in Nigeria, is a member of the CGIAR crop improvement centers. In an ongoing effort to improve the NUE of maize varieties adapted to West and Central Africa, IITA has operated a breeding program focused on NUE for nearly 15 years, coordinated most recently by Dr. Abebe Menkir. This breeding program is the main source of germplasm for improved varieties in Western and Central Africa. However, IITA and other institutions in Africa have limited facilities and expertise to take advantage of resources for maize genomics research. We are develop avenues for information exchange between our project and scientists at IITA that will allow us to determine whether candidate genes identified through the analysis of B73 x Mo17 and IBMRI x IHP1 hybrids are relevant to improving NUE in maize germplasm adapted to West and Central Africa.

Our collaboration has four general objectives:

1. to support reciprocal visits between a graduate student working with IITA collaborators and the project scientists, where the graduate student will be trained in sampling and analysis methods for NUE and its component traits
2. to assess in field trials the physiological strategies being employed by IITA maize varieties with improved NUE, including amino acid profiles under low N conditions
3. to evaluate IHP1 as a germplasm source for improving NUE in African maize
4. to conduct RNA expression profiling to assess patterns of N-responsive gene expression and genetic variability among the best IITA maize varieties for NUE.

This collaboration will provide a number of significant benefits to agricultural production in Western and Central Africa. The exchange of ideas, approaches, and data will further enhance the breeding efforts of IITA to increase maize NUE. Because IITA is a major provider of maize germplasm to sub- Saharan Africa, any improved varieties will be rapidly disseminated to farmers in these areas. The adoption of maize varieties with better NUE will raise yields of the maize crop in West and Central Africa while using less supplemental N–a prospect that not only reduces input and energy costs, but also decreases the potential N pollution of scarce water supplies in the region.