Mini Core Collections for Efficient Utilization of Plant Genetic Resources in Crop Improvement Programs. Information Bulletin No. 78

Plant genetic resources are the basic raw materials for crop improvement to enhance productivity and an insurance against unforeseen threats to agricultural production. Continuous progress in crop improvement depends on discovery of new sources of genetic variation, accurate identification of lines with beneficial traits, and their judicious use. Core collections (~10% of the entire collection) and mini core collections (~10% of the core or ~1% of the entire collection) have been suggested as a gateway to enhanced utilization of germplasm by crop improvement scientists. Using passport, characterization and evaluation data, core and/or mini core collections have been developed in chickpea, groundnut, pigeonpea, pearl millet, sorghum, finger millet and foxtail millet at ICRISAT, Patancheru, India. Evaluation of these subsets has resulted in identification of new sources of genotypic variation: drought and salinity tolerance in chickpea, groundnut and pigeonpea; low temperature tolerance (at germination) in groundnut; sorghum stalks with high sugar content; resistance to pest and diseases in chickpea, groundnut, pigeonpea and sorghum; early maturity, large seed size and/or high grain (or pod) yield in chickpea and groundnut; early maturity and high grain yield in pigeonpea; and high grain and fodder (green) yield in pearl millet, finger millet and foxtail millet. The concept and process of developing mini core has been recognized worldwide as an “International Public Good” (IPG). Many national programs have shown immense interest in evaluating mini core for identification of new sources of variation for use in crop improvement programs. To date, 84 sets of mini core of chickpea, groundnut, pigeonpea, sorghum, pearl millet, foxtail millet and finger millet have been supplied to researchers in 13 countries. Feedback revealed that researchers in national programs were able to identify new sources of variation for beneficial traits such as early maturity, resistance to pest and diseases, large seed size, and high grain yield. Seeds of mini core collections are available to researchers globally for research and training.

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