Grafted Tomato Production Under Different Planting Densities

Given the improved vigor of grafted vegetable plants, reducing plant population in field production has been proposed to lower the cost of using grafted plants. In this study, grafted tomato trials were performed during Fall 2013 and Spring 2014 in certified organic field in Citra, FL, under five in-row spacing treatments including 0.46, 0.61, 0.76, 0.91, and 1.07 m, with a constant between-row spacing of 1.83 m. Determinate tomato scion ‘Tribute’ was grafted onto two commercial tomato rootstocks ‘Multifort’ and ‘RST-04-106-T’, respectively. Non-grafted ‘Tribute’ was included as the control. The experiments were arranged in a split-plot design with plant spacing as the whole-plot factor and grafting as the subplot factor. In addition to fruit yields, root-knot nematode (RKN) galling was evaluated due to the natural RKN infestation in the field. Results from this two-season study will be discussed to explore the feasibility of modifying the planting density in field production of grafted tomatoes for improving economic returns.