Efficacy of acibenzolar-S-methyl and two strobilurins, azoxystrobin and trifloxystrobin, for the control of corky root of tomato and verticillium wilt of eggplant

The efficacy of two fungicides, azoxystrobin and trifloxystrobin, and a plant defense activator, acibenzolar-S-methyl, for the control of tomato corky root and eggplant verticillium wilt, was evaluated under greenhouse and field conditions by means of dips, soil drenches or foliar sprays. The strobilurins provided excellent control of the two diseases under greenhouse conditions. Azoxystrobin was more effective than trifloxystrobin and reduced the severity of tomato corky root and eggplant verticillium wilt by 98% and 95%, respectively. Acibenzolar-S-methyl caused plant stunting and severe leaf chlorosis in the greenhouse experiments. In the field, azoxystrobin provided the best control. Tomato corky root severity was reduced by 83% and eggplant verticillium wilt severity by 29%. At the dosage used, acibenzolar-S-methyl was effective only in controlling tomato corky root. No phytotoxic symptoms were observed by any material in the field.