Progress In Marker-Assisted Breeding For Drought Tolerance In Chickpea

Terminal drought is the most serious abiotic stress in chickpea (Cicer arietinum L.) as the crop is largely grown rainfed on residual soil moisture in the post-rainy season. The breeding strategies to minimize losses from terminal drought stress include development of short duration varieties which can escape terminal drought and improving drought avoidance/tolerance. A genomic region, which probably contains a transcriptional factors or several QTLs affecting root traits (root length density and total root biomass) and other traits related to drought tolerance and yield traits, was introgressed in three popular cultivars (JG 11, KAK 2 and Chefe) through marker-assisted back crossing (MABC). A set of 20 BC3F4 lines generated from the cross involving JG 11 as recurrent parent was evaluated at 3 locations in India (Patancheru, Nandyal, Gulbarga) and one each in Kenya (Koibatek) and Ethiopia (Debre Zeit). Several BC3F4 lines giving significantly higher yield (up to 11.4% higher yield under rainfed condition and up to 24.2% higher yield under irrigated condition) than the cultivar JG 11 were identified at each location. The MABC lines with recurrent parent KAK 2 and Chefe and additional lines with recurrent parent JG 11 are being evaluated at four locations in India, two locations in Kenya and one location in Ethiopia during 2012/13. Efforts are also being made to introgress this genomic region into several other cultivars from India and sub Saharan Africa. The initial results from the evaluation of MABC lines are encouraging and suggest the scope of effective use of marker-assisted breeding for improving drought tolerance in chickpea