|Managing Bacterial wilt of Tomatoes in North Carolina through Grafting with Disease Resistant Rootstocks|
E. J. SILVERMAN (1), J. Driver (1), J. Kressin (1), F. Louws (1), D. Panthee (1). (1) North Carolina State Univ, Raleigh, NC, U.S.A.
Bacterial wilt, caused by <i>Ralstonia solanacearum, Rs,</i> is endemic to many temperate regions around the world causing enormous economic loss in crops like potato, tobacco and tomato. Management of BW, is difficult and is centered on extended crop rotation, cultural practices, host resistance and grafting. The goal of this project was to examine the efficacy of grafting with BW resistant tomato rootstocks in NC on-farm trials and develop better recommendations for growers to reduce the impact of BW. Ten BW rootstocks grafted to the common scion ‘FL47’ were evaluated over two growing seasons in a high BW pressure field in western NC. Rootstock selection impacted disease incidence. In 2012, rootstock varieties ‘Cheong gang’, BHN1054, DP106, and CRA66 exhibited the least number of diseased plants with 25, 33, 35, and 43% respectively. Non-grafted and self-grafted ‘FL47’ controls reached 100% plant death by 75 days after planting (DAP). Similar results were observed in 2013 with rootstocks CRA66, DP106, HI7997 and ‘Cheong gang’ possessing the lowest BW disease incidence with 4, 8, 9, and 10% wilt, respectively. Non-grafted and self-grafted controls reached 70 and 63% disease by 77 DAP. Marketable yields were dramatically impacted with high yields from plots with superior resistance compared to the susceptible controls. Based on regional experiments, several large commercial farms have adapted grafting as an IPM tool to manage BW.