2018 ASHS Annual Conference

Successful integration of vegetable grafting into current tomato production practices could open new opportunities for the Texas tomato industry to exploit vigorous rootstocks for effectively managing soil diseases, abiotic stresses, and improve fruit quality and yield. A multi-location (Uvalde, Overton, and Weslaco) trial was conducted to evaluate the yield performance of grafted tomatoes in protected environment and open-field conditions during the growing season of spring of 2017. In each location, two determinate tomato cultivars, TAMU Hot and Tycoon, were grafted onto two interspecific hybrid rootstocks, ‘Estamino’ and ‘Multifort’. Non-grafted ‘TAMU Hot’ and ‘Tycoon’ were used as controls. Field experiments were arranged in a randomized complete block design with four to five replications, depending on location. Yield performance of the graft combinations varied with location and production system. In the Uvalde location, the high tunnel system enhanced marketable yields by 116% to 161% relative to open-field system, with an additional of 8% to 23% significant increase due to grafting with interspecific rootstocks. Yield increase in grafted plants was mainly due to significant increases in average fruit weight. In the Overton location where only open-field trial was conducted, grafting 'Tycoon' on ‘Estamino’ and ‘Multifort’ significantly increased the marketable yield by 59% and 44%, respectively, as compared to the non-grafted control. Similar yield increases due to the grafting were also achieved under open-field conditions in the Weslaco location, although yield levels were generally lower than those of other locations. Results from this study demonstrate that grafting along with protected environment system clearly have the potential to significantly increase tomato production across Texas regions.