Investigating the effects of moisture stress (water scarcity) on the morphological and physiological characteristics of five basil cultivars

Basil is a medicinal plant as well as a vegetable, and its economic importance is due to its use in health and pharmaceutical industries. Also, moisture stress (water scarcity) is one of the environmental factors leading to a decrease in the yield of any plant. In this study, the effect of moisture stress on the morphological and physiological traits of basil medicinal plant was evaluated as a split plot experiment based on a completely randomized design with three replications in the greenhouse. The results of variance analysis showed a significant difference at the probability level of 1% for the moisture stress effect as well as the genotype effect. The moisture stress × genotype interaction effect was significant for all traits, which means that the genotypes have shown different reactions under moisture stress. The moisture stress caused a significant decrease in most traits while it increased leaf proline. The highest accumulation of proline with an average of 0.0041 mg per gram of fresh weight was related to the Red Rubins basil variety under no-stress conditions and then the Iranian green basil variety with an average of 0.0029 mg per gram of fresh weight under medium moisture stress conditions. The maximum amount of growth characteristics (leaf length, number of leaves, leaf yield and shoot weight) was related to Iranian purple basil cultivar under without moisture stress conditions. Also, the genotype of Iranian green basil can be further investigated in future breeding programs due to its greater tolerance to moisture stress conditions.