Effects of biological and chemical treatments on Botrytis stem canker and fruit yield of tomato under greenhouse conditions

Experiments were conducted to identify, by in vitro dual culture tests, pot ential biological control agents producing antibiotics and to evaluate sele cted biological and chemical agents for control of stein canker caused by B otrytis cinerea on tomato plants (Lycopersicon esculentum) grown in yellow cedar sawdust in a research greenhouse. Four strains of Bacillus subtilis a nd one each of Enterobacter agglomerans and Rhodosporidium diobovatum were antagonistic towards B. cinerea in dual culture. Lesions in treatments with RootShield(R) and a strain of R. diobovatum were significantly shorter com pared with the inoculated control. Plants treated with RootShield(R) or R. diobovatum had significantly higher total fruit yield than the inoculated c ontrol. The treatments with RootShield(R), SoilGard(R), and R. diobovatum p roduced significantly more total fruits than the inoculated control. The nu mber of dead plants were significantly lower in treatments with RootShield( R) and R. diobovatum compared with the other treatments and inoculated cont rol. These results suggest that RootShield(R) and R. diobovatum have the po tential to control Botrytis stein canker and increase the fruit yield of to mato under greenhouse conditions.