Effect of Commercial Biofumigant Cover Crops on Growth, Yield and Disease of Processing Tomatoes

Glucosinolate-producing cover crops are being marketed as biofumigants to reduce soil-borne diseases and increase yields. 'Caliente 119' (Brassica juncea and Sinapis alba), 'Caliente 99' and 'Caliente 61' (B. juncea) and 'Nemat' (Eruca sativa) were tested for their effects on growth, yield and incidence of anthracnose, blossom end rot and minor fruit rots of processing tomatoes at OARDC research stations in Fremont and Wooster, in 2006. Spring-seeded 'Caliente 119', 'Caliente 99' and 'Caliente 61' produced similar amounts of biomass, significantly higher than that produced by 'Nemat' in both locations. 'Caliente 119', 'Caliente 99' and 'Caliente 61' were significantly taller than 'Nemat' plants, but 'Nemat' population density was higher than recorded for the mustard varieties in Fremont. There were no differences among cover crops in germination in Wooster. In Fremont, there were no significant differences between plots with or without cover crops in tomato growth parameters, total or marketable yield, or percentage of fruits with anthracnose or blossom end rot. In Wooster, tomatoes following 'Caliente 119', 'Caliente 61' or 'Nemat' were shorter than plants not following a cover crop. Tomato plant width and number of leaves per plant were less in tomatoes following any cover crop than the non-cover control. Total fruit yield was lower in tomatoes following 'Caliente 119', 'Caliente 99' and 'Caliente 61' than the control, but there were no differences in marketable yield or yield of fruit with anthracnose. Minor fruit rots were lower in tomatoes following 'Caliente 99' and 'Nemat' than the control in Fremont. However, minor fruit rots were higher in tomatoes following 'Nemat' than the control in Wooster.