Effect of Drought and Salt Stress on Growth, Osmolytes Protein and Isozymes in Vicia faba L. Genotypes

PLANTS regularly face adverse growth conditions, such as drought and salinity. These stresses can delay growth and development, reduce productivity, and, in extreme cases, cause plant death. Plant stress responses are dynamic and
involve complex cross-talk between different regulatory levels, including adjustment of metabolism and gene expression for physiological and morphological adaptation. In this concern, two pot experiments in split plot design were conducted to investigate the response of five divergent faba bean genotypes namely (NBL- Mar.3(G1), NBL-5(G2), L3(G3), Nubariya-1(G4) and Misr-1(G5)) against drought or salt stress. Expose the faba bean genotypes (1, 2, 3, 4 and 5) to water and salt stress leads to significant decrease in fresh and dry weight, total protein and NPK%. Tolerant
genotypes (G1 and G2) have high protein content than sensitive genotypes (G4 and G5). Drought and salt stress induced an accumulation of total phenolic compound and total free amino acids. Aliphatic unsubstituted amino acids and cyclic amino acids increased under drought and salt stress in all genotypes. This was accompanied by a marked increase in the proline content. Aliphatic substituted amino acids decreased in tolerant genotypes and increased in sensitive genotypes under drought and salt stress. The biochemical response diversity in susceptible and tolerant faba bean varieties is discussed.