Enhanced Utilization of Germplasm for Increased Genetic Gains in Breeding Programs.

Enhanced utilization of germplasm for increased genetic gains in breeding programs

Hari D Upadhyaya

Genebank, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana 502 324, India

Abstract

Productivity of many crops including, rice, wheat and maize, which increased drastically following adoption of improved technologies including seed, is currently either stagnated, declined or showing only marginal increase. This makes feeding the growing world population, safe and nutritious food a greatest challenge particularly in view of negative effects of climate change and depletion of natural resources on agriculture. Genetic gain, defined as the annual increase in yield realized through crop breeding, is currently <1.0 year^-1 in many crops and needs to double to achieve global food and nutritional security. Plant genetic resources are the basic raw materials to power current and future progress in crop breeding programs. Globally, 7.4 million accessions are conserved in about 1800 genebanks. However, most breeding programs use working collections and low use of germplasm (<1%), leading to a narrow genetic base in most crop cultivars, is a major concern. ICRISAT genebank at Patancheru, India has the largest collection (125,043 accessions from 144 countries) of its mandate crops and small millets, crops important for drylands. To enhance utilization of germplasm representative core (10% of entire collection) and mini core (10% of core or 1% of entire collection) have been developed, systematically evaluated in partnerships with national programs and genetically diverse multiple trait (biotic and abiotic stress resistant, nutritional, agronomic) germplasm identified for use. Use of such germplasm has resulted in developing exceptionally high oil (up to 63%, compared to ~48% in control cultivar) and high-yielding groundnut breeding lines, contributing to enhanced genetic gains. Crop wild relatives harbour genes for stress tolerance, yield and nutritional traits, and their use in groundnut through amphidiploids has resulted in identifying cryptic introgression lines having improved yields, 100-seed weight, and drought tolerance. Availability of ample genetic and genomic resources, and high throughput phenotyping has opened gateway to accelerate genetic gains.