Integrating genomics and mapping approaches to improve pearl millet productivity in drought prone regions of Africa and Asia

Pearl millet [Pennisetum glaucum (L.) R. Br.] is the staple cereal crop grown by subsistence farmers in the hottest, driest regions of sub-Saharan Africa and the Indian subcontinent where rain-fed crop production is possible. Unreliable and scant rainfall is the most important factor contributing to low grain and straw yields and poor yield stability of this crop. Efficient breeding for drought-prone environments requires selection strategies that are sufficiently independent of the variation inherent in the natural environments to permit identification and use of true genetic differences. The project will conduct targeted genetic mapping of a genomic region associated with a major drought tolerance QTL on LG 2 in pearl millet and identify closely-spaced gene-based markers associated with this QTL. An agronomically-elite near-isogenic population that segregates only for the genomic region associated with the drought tolerance QTL will be mapped with a wide range of novel markers identified using comparative mapping methods. In a complementary approach, association of these markers to the drought tolerance QTL will be tested by conducting association genetic analysis to identify more generic gene-based markers within the QTL. The tightly linked gene-based markers associated with the drought tolerance QTL thus identified will then be used to transfer this important QTL into a number of elite genetic backgrounds adapted to locations in Africa and Asia, using marker assisted back crossing. The near-isogenic lines developed will also be evaluated at various sites in Africa and Asia to confirm the effect of the QTL in a range of environments and to identify morpho-physiological traits associated with improved drought tolerance. Generic knowledge and methodologies developed in this project will contribute to the global pool of knowledge in this important research area and facilitate increased crop production in water-limited environments globally