Characterisation of drought-induced alterations in seed protein characteristics of Cicer arietinum L.

To study the impact of drought stress on seed protein quantity and quality of Cicer arietinum (chickpea), different chickpea cultivars, including the drought-tolerant (HC5) and drought-sensitive (HC1), were subjected to varying levels of drought stress (Control, L1- 10% soil moisture, L2- 5% soil moisture). The total seed protein content increased in both genotypes under drought stress, with a comparatively higher increase (2.7%) in the drought-tolerant genotype. In the HC5 genotype, the proportions of albumins and prolamins decreased, while globulins and glutelins increased under reduced soil moisture conditions. The drought-sensitive genotype showed a similar trend, although the changes were less pronounced. Amino acid analysis revealed variations in tryptophan, methionine, and cysteine content in different protein fractions isolated from seeds of drought-stressed plants. The SDS gel electrophoretic analysis of the four seed protein fractions primarily revealed quantitative alterations in the polypeptides with minor qualitative alterations under drought stress. Thus, our study revealed that drought stress impacts seed protein quality in chickpea by affecting the proportion of four protein fractions and the content of sulphur-containing amino acids.