Water deficit stress condition alters stress metabolites and essential oil content of coriander (Coriandrum sativum L.)

Changes in relative water content (RWC), stress metabolites and essential oil (EO) contentwere studied in five genotypes of coriander during water deficit stress at 70 days after sowing (DAS) and 90 DAS. Leaf samples were taken for RWC and stress metabolites analysis while seeds were taken for estimation of EO content. A significant reduction in RWC was observed in all the genotypes at both the critical stages water stress. Coriander genotype UD-07 and UD-31 had lowest reduction, it can be inferred that genotype UD-07 had best tolerated to water deficit stress condition followed by UD-31. Induced water deficit stress declined membrane stability index with concomitant increase in the lipid peroxidation product malondialdehyde in all genotypes at both stages. Genotypes UD-07 and UD - 31 were found to have higher stability indices and a significantly lower accumulation of the malondialdehyde (MDA). Accumulation of osmo-protectant L-proline was significantly increasedin all genotypes at both stages, however highest induction was observed in genotype UD-07 and UD-31. EO content was increased in all genotypes under water deficit stress; however it was slightly increased in genotype UD-07 and UD-31. These results showed that genotype UD-07 and UD-31 had better physiological and biochemical mechanisms to combat water deficit stress.