2019 ASHS Annual Conference

Grafting for vegetable crops has been in use for decades and much research has been conducted in the United States to ascertain potential benefits for commercial producers. The emphasis has been well placed on field vegetable production and the potential for grafting to address disease issues, increase yield, and lower risk in these commercial operations. Interestingly, as the research has progressed to determine management needs and cost-benefit models, there has been concurrent marketing to non-commercial audiences. Many of the same potential benefits of grafting exist for gardeners and other non-commercial growers, but economic hurdles to adoption can be lower for these small-scale growers. There are many avenues for benefit in the use of grafted tomatoes for gardeners, including overcoming disease limitations in relatively fixed garden sites, reduction of management time, and the opportunity to reduce plant number due to yield increases. However, field research directed to non-commercial audiences has been less investigated. Further elucidation as to which tomato cultivars and settings would be most impactful for gardeners to incorporate grafting would support the highest return on investment in the use of grafted plants. This project was designed to address the use of grafted tomatoes in non-commercial settings by using cultivars and management methods applicable to this audience. Three years of trials were conducted in Knoxville, Tennessee, using representative indeterminate and determinate tomato cultivars. One grafted rootstock (‘Emperador’) was used with several scions in comparison to ungrafted scion plants. ‘Big Beef’, was grown in all three years, and five comparison hybrid and heirloom cultivars were used to ascertain potential benefits for determinate and indeterminate cultivars. In the trial site without known history of soil borne disease issues, results showed there was a potential for yield increases in both hybrid and heirloom indeterminate tomato cultivars. This presentation will include an overview of trial results and discuss potential beneficial areas of grafted plant use for non-commercial growers.