Induction of defence related enzymes and biocontrol efficacy of Trichoderma harzianum in tomato plants infected with Fusarium oxysporum and Fusarium solani

Abstract

Fusarium wilt of tomato plants caused by Fusarium oxysporum Schlecht. emend. Snyder & Hansen and Fusarium solani (Mart.) Sacc. are serious problem limiting tomato production worldwide. Biological control has emerged as one of the most promising alternatives to chemical fungicides. The biological control capability of a T. harzianum isolate against F. solani and F. oxysporum has been investigated. It inhibited colony growth of two Fusarium species by more than 80 % in dual culture tests. Results of greenhouse experiments revealed that disease severity in the tomato plants co-inoculated with T. harzianum was significantly lower than plants only infected with the Fusarium pathogens. Tomato plants inoculated with the antagonistic T. harzianum isolate, showed enhanced peroxidase and polyphenol oxidase activities in greenhouse experiments and increased resistance to F. solani and F. oxysporum. The T. harzianum isolate indirectly affected the Fusarium pathogens by enhancing plant defence.

Keywords

• fungal pathogens
• antagonistic fungus
• peroxidase
• polyphenol oxidase
• plant growth and biological control