Alleviation of salt injury of cucumber plant by grafting onto salt tolerance rootstock

Abstract

Experiment was conducted in a greenhouse during the two successive seasons of 2008- 2009 and 2009-2010 to investigate the effect of grafting technique in improving salt tolerant of grafted cucumber plants (Cucumis sativus L. cv. falcon, Hybrid F1) under saline conditions. Samples were taken at 70 days after planting to determine plant growth, leaf electrolyte leakage percentage (Membrane Permeability) and leaf relative water content (LRWC). As well as, fruits yield and quality, biochemical analyses and antioxidant enzymes activity. Grafting of cucumber on salt tolerance rootstock (Shintosa Supreme pumpkin) significantly increased growth parameters by 44% and 69% for fresh weight, dry weigh by 41% and 69%, plant height 86% and 83% and leaf area by 102% and 57% in both season respectively and enhancement 12% and 13% in leaf relative water content (LRWC) as compared to ungrafted cucumber in both season. Furthermore, These positive effects of grafting cucumber was correlated with significantly increased in chlorophyll, carotenoid, proline and total soluble protein concentrations. Although, grafting reduced membrane permeability and malondialdehyde (MDA) concentration in leaves of cucumber plants under salt stress conditions. As well as, improved fruit number, fruit weight, number of harvest and fruit yield comparing with ungrafted plants. As well as, Grafting increased PAL, POD, CAT, SOD, PPO and APX activities as compared to ungrafted plants under saline conditions. Excluding, grafted plants significantly reduced titratable acidity (TA %), total soluble solids (TSS %) and electrical conductivity (EC) in fruit juice as compared to ungrafted plants.