Variation in Morpho-Physiological Responses of Desi Chickpea (Cicer arietinum L.) Seedlings to Progressive Water Stress

Water deficit stress is one of the key determinants causing crop yield losses globally. The present study was conducted to effectively screen Desi chickpea genotypes based on early dehydration tolerance-related traits as a tool for further evaluation in field experiments. Sixty-four genotypes of Desi chickpea were assessed under progressive water deficit stress, resulting in high variability in early growth characteristics and traits. The clustering analysis with UPGMA, separated the genotypes into three major groups, in accordance with biplot analysis grouping. The highest root length density was observed in the MCC438 genotype with an 18.6-fold increase compared to MCC884 which showed the lowest root length density among all analyzed chickpea genotypes. The genotypes MCC32 and MCC539 produced the higher shoot and root dry weight, while MCC884 showed the lowest value (with 12- and 32.5-fold differences, respectively). Ten genotypes showed differences in terms of their overall response to the water deficiency stress, including eight tolerant genotypes (MCC320, MCC418, MCC425, MCC438, MCC539, MCC540, MCC560, MCC576) and two susceptible ones (MCC433 and MCC897), were selected for further investigation of various growth and physio-biochemical traits based on drought response indices. A clear distinction was observed among ten analyzed genotypes for some physio-biochemical traits, indicating their tolerant responses to drought stress. Drought-tolerant candidate genotypes showed higher indices of seedling growth parameters, proline content, RWC, membrane stability, and root-to-shoot ratio in comparison to drought-susceptible candidate genotypes. The genotypes MCC425, MCC438, MCC418, and MCC539 were found more drought tolerant in the seedling stages, whereas genotype MCC433 was more sensitive. These results were consistent with what was obtained in our preliminary study. However, these results should be addressed further in the field conditions.