Chickpea breeding for water-limited environments

Chickpea (Cicer arietinum L.) is a dry season food legume and is largely grown on residual soil moisture after the rainy season. The crop often experiences moisture stress towards the end of the crop season (terminal drought). The crop may also face heat stress at the reproductive stage, if sowing is delayed. The increasing climate variability, reflected in wide fluctuations in temperatures and rainfall, is further aggravating risks of terminal drought and heat stresses to chickpea crop, particularly in the semi-arid tropics (SAT). The genetic approaches being used for managing terminal drought and heat stresses include development of varieties with early maturity and enhanced tolerance to these stresses. Excellent progress has been made in the development of early maturing varieties with high yield potential, which helped in bringing additional area under cultivation and enhancing productivity of chickpea in short-season SAT environments. Several varieties with improved drought tolerance have been developed by the classical approach of selecting for grain yield under moisture stress conditions. Similarly, selection for pod set in the crop, subjected to reproductive stage heat stress by delayed planting, has helped in development of heat-tolerant varieties. A genomic region called “QTL-hot spot”, which controls a number of drought tolerance traits including root traits, has been introgressed into several popular cultivars using marker-assisted backcrossing (MABC); and introgression lines giving significantly higher yield than the popular cultivars under moisture stress conditions have been identified. Multi-parent advanced generation inter-cross (MAGIC) approach has been found promising in enhancing genetic recombination and developing lines with enhanced tolerance to terminal drought and heat stresses. Integrated breeding approaches involving, particularly, genomic tools, precision phenotyping, and rapid generation turnover techniques, have improved efficiency of chickpea breeding programs in developing varieties better adapted to water limited environments.