Studies on Physiological, Biochemical and Molecular responses of Lentil (Lens culinaris) Genotypes under Abiotic Stresses

Abstract

Lentil (Lens Culinaris) is a significant global pulse crop cultivated in countries like India and Canada. However, the production of lentil faces significant challenges due to abiotic stresses. While it exhibits moderate tolerance to drought and salinity, its productivity is substantially diminished by intermittent and terminal drought as well as salinity. These stress conditions instigate a cascade of morphological, physiological, biochemical, and molecular transformations that detrimentally impact the plant's growth and yield. To enhance stress tolerance in lentil plants, a thorough understanding of how various abiotic stress factors, such as drought and salinity, affect the plant at a molecular and physiological level is essential. In this study, the drought and salinity tolerance of ten lentil genotypes (DPL-15, DPL-62, IPL- 81, IPL-316, IPL-406, K-75, JL-3, L-4076, PDL-1, PDL-2) were examined. Drought stress was induced by subjecting the plants to PEG 6000 (18% w/v) for 15 days, while salt stress was imposed using 200mM NaCl for the same duration. The objective was to analyse various morphological, physiological (Chlorophyll content, relative water content, and Membrane stability index) and biochemical parameters (Catalase test, total soluble sugar, anthocyanin, and proline contents) under drought and salt stress conditions. The current research focuses on the molecular characterization and functional significance of abiotic stress-tolerant genes (DREB2a, F-Box, LEA4, SOS1, ASR) from lentil (Lens culinaris). Through a series of analyses, including conserved domain search, protein structure prediction and validation using Swiss Model, Swiss-PDB viewer, and Expasy, the study establishes the involvement of these hypothetical proteins in regulating responses to drought and salt stress. Furthermore, an expression analysis was conducted for abiotic stress-tolerant genes (DREB1A, DREB2A, F-Box, LEA4, SOS1, SPS, ASR, Wrky41) to gain a better understanding of how these genes respond to the drought and salt stress. The results will contribute to better understanding the mechanisms of drought and salinity tolerance in lentil genotypes, potentially aiding in the selection of suitable parents for breeding drought-resistant and salt-resistant varieties. This investigation has the potential to identify novel abiotic stress-tolerant genes that play pivotal roles in drought and salt tolerance. Additionally, it aims to develop functional markers that could be utilized to enhance lentil crops. Moreover, the study offers fundamental insights into the drought and salt tolerance capacity of the studied genotypes, which could be further validated at the field level.