Grafting enhances drought stress tolerance by regulating stress-responsive gene expression and antioxidant enzyme activities in cucumbers

Résumé

Abstract Water scarcity is a major limiting factor for crop yield production in arid and water-stressed areas worldwide. Cucumber plants have a high transpiration ratio and are vulnerable to water stress. Grafting commercial cultivars onto selected strong rootstocks has been useful in mitigating the effects of water stress. Therefore, this study aimed to evaluate the possibility of using a novel rootstock plant’s tolerance to water-deficit stress in inducing drought tolerance in cucumbers by activating the stress-response gene expression and the antioxidant system, which improved the cucumber quality and yield under water-deficit conditions. This field experiment was conducted for >2 years, 2020 and 2021, with five water stress cultivars (i.e., rootstock) and drought-sensitive cultivar Luerans (i.e., a scion). They were subjected to various deficit irrigation levels for 12 days, and their agro-physiological and molecular responses to water-deficit stress were assessed. Our results showed that the agronomical parameters, including the leaf area, leaf water content, number of leaves, plant height, root dry matter shoot dry matter, rates of leaf appearance and stem elongation, and total yield significantly increased with grafted cucumber plants than with nongrafted cucumber plants (control) under normal and stressful conditions. The physiological parameters revealed that higher catalase and peroxidase activities, abscisic acid levels, gibberellic acid accumulation, and lower lipid peroxidation (malondialdehyde) significantly increased the plant growth rate in rootstock-grafted genotypes. Furthermore, the real-time polymerase chain reaction expression results revealed that transcript levels of the stress-response genes CsAGO1 and CsDCLs increased rapidly and continuously in five rootstock grafting. Concurrently, these findings suggest that grafting with local varieties of novel drought-tolerant rootstock genotypes could improve water stress tolerance in drought-sensitive cucumber cultivars.

Citer ce document

Accès au document

Ce document est hébergé sur son dépôt institutionnel d'origine.

Auteur(s)

Statistiques

Consultations : 1

Téléchargements : 0