Abstract
Water deficit in semi-arid areas is the main limiting factor affecting crop production and quality. Suitable strategies for water management, such as water regimes and grafting, can be helpful for the sustainability of agriculture and overcoming drought stress. Responses of two greenhouse-tomato cultivars (Durinta and Valouro F1) grafted onto three rootstocks (Beaufort, Maxifort, and Spirit) to water stress were evaluated using three irrigation water regimes (50, 75, and 100% crop evapotranspiration [ETc]). The results showed the efficiency of grafting increases in total yield, and contents of vitamin C (VC), total soluble solids (TSS), calcium (Ca2+), and potassium (K+). Beaufort rootstocks produced better quality plants and higher yield compared to Maxifort or Spirit rootstocks. Under 100% ETc, Durinta cultivars had higher fruit number and weight, total yield, and Ca2+ and K+ concentrations, but under high water stress, VC, TSS, and TS contents increased. Durinta grafted onto Beaufort rootstocks (DB) had higher total yield percentages (40.36-52.49% and 73.78-100.73%) than non-grafted Durinta and Valouro plants, respectively. Thus, we recommend grafting of tomato scions (Durinta) onto Beaufort rootstocks as an acceptable practice for greenhouse producers, because DB increased crop yield while saving approximately 25% of irrigation water. Moreover, it is an effective practice for industrial and fresh market production of tomato because of the high TSS and VC contents.