The Effect of Grafting on Morphological, Physiological and Molecular Changes Induced by Drought Stress in Cucumber

Abstract

Drought is one of the most important abiotic stress factors affecting crop yields and qualities worldwide. One drought-sensitive plant is the cucumber, which has a high transpiration rate. Grafting is recognized as a promising approach to increasing tolerance to abiotic stresses in cucumber. In this study, it is aimed to determine the rootstock that will prevent negative changes in some growth, physiological and genetic parameters of cucumber under drought stress and to determine the mechanism of the system. In drought stress conditions, leaf number values were found to be 6 on average in non-grafted plants and between 6–13.16 in grafted plants. Average leaf fresh weight values (7.56–9.84 g) obtained from grafted plants were higher than non-grafted plants (5.7 g). Leaf chlorophyll content (SPAD) values were found to be between 24.43 in non-grafted plants and 37.83–55.36 in grafted plants under stress conditions. Malondialdehyde (MDA) concentration values also decreased from 5.66 to 3.23–4.36 in grafted plants. It was determined that the genomic template stability (GTS) rate was 64.1% in the non-grafted treatment group. DNA polymorphisms detected by ISSR (inter simple sequence repeat) can be used as a biomarker system for the detection of genotoxic effects of abiotic stresses, such as drought. These findings suggest that grafting with drought-resistant rootstocks may improve drought tolerance in drought-sensitive cucumber genotypes.