Direct antagonistic activity of chitinase produced by Trichoderma sp. SANA20 as biological control agent for grey mould caused by Botrytis cinerea

摘要

Trichoderma has been used as a biological control agent against grey mould in major crops because of its large variety of antagonistic mechanisms. In the present study, Trichoderma sp. SANA20 was isolated from Japanese apricot bark as a biological control agent for grey mould caused by Botrytis cinerea . SANA20 suppressed B. cinerea hyphal growth but did not show mycoparasitism on media using the dual culture technique. SANA20 decreased B. cinerea induced grey mould disease severity in cucumber leaves. The biocontrol activity of SANA20 culture media toward B. cinerea induced grey mould disease suggested that the antagonistic activity of SANA20 toward B. cinerea was dependent on substances secreted by SANA20. SANA20 produced and secreted chitinase, which can degrade fungal cell wall, in culture media. Purified chitinase from SANA20 culture media also decreased the severity of grey mould in cucumber leaves, suggesting that chitinase production by SANA20 played a critical role in the biological control of B. cinerea . SANA20 is expected to contribute to the further improvement of integrated pest management strategies for combating B. cinerea and to potentially suppress the heavy use of chemical fungicides in the field.