Identification and Evaluation of Chickpea Germplasm for Tolerance to Heat Stress

Global warming and extreme temperatures are predicted in the future, hence identification of appropriate varieties that could adapt to such changes is imperative for sustaining crop productivity. Thirty-five early maturing chickpea (Cicer arietinum L.) germplasm accessions were evaluated for their tolerance to heat stress. Plant traits such as plant width, flowering duration, days to maturity, pod number, seed weight, grain yield and per-day productivity were affected under heat stress. Genotypes differed in their sensitivity to heat stress, and the yield loss among genotypes varied from 10 to 15% of potential yield for every degree increase in temperature beyond the optimum temperature range. Multiple regression analysis indicated that the plant trait expression can be predicted accurately for the assumed change in climate on the basis of mean temperature, daylength, duration of bright sunshine, incident solar radiation, relative humidity, wind velocity, and potential evaporation. Mitigation of heat stress by irrigation and application of additional nitrogen to the crop resulted in sustaining the potential yield (up to 80%). ICC 14346 showed high tolerance to heat stress and could be used as a parent in crop improvement research. ICC 5597, ICC 5829, ICC 6121, ICC 7410, ICC 11916, ICC 13124, ICC 14284, ICC 14368, and ICC 14653 were heat stress tolerant, responsive to irrigation and nitrogen management, and consistently high yielding (>1400 kg ha(-1)) compared with the control ICCV 92944 (1333 kg ha(-1)).