Identification of Diverse Trait-Specific Germplasm for Use In Crop Improvement Using Mini Core Strategy.

Plant genetic resources form the raw material for developing high yielding cultivars. About 7.4 million accessions of various economically important crops have been conserved globally. However, in most cases <1% accessions have been used in crop improvement, mainly due to lack of knowledge on traits of economic importance. The genebank databases do not have information that meets breeders’ needs on trait-specific, genetically diverse and agronomically desirable accessions that can be used as parents in breeding programs.  To meet such needs, multilocational replicated evaluation is required which is not feasible with large germplasm collections. The mini core collections (10% of core or 1% of entire collection) serves as an efficient and convenient option for extensive evaluation and identification of accessions with desirable agronomic traits including resistance to  abiotic and biotic stresses and for nutritional quality traits. Using the mini core collection approach, the researchers  at ICRISAT and in national programs have identified diverse sources of resistance/tolerance for many biotic and abiotic stresses, and for agronomic and quality traits in chickpea, groundnut, pigeonpea, sorghum, pearl millet, foxtail millet and finger millet. This is expected to enhance the use of germplasm in crop improvement. Molecular characterization of the mini core collections have resulted in identification of genetically diverse trait-specific germplasm lines meeting the needs of breeders for use in developing high yielding cultivars with a broad genetic base.