Pepper growth promotion and Fusarium wilt biocontrol byTrichoderma hamatumMHT1134

Pepper wilt, caused byFusarium oxysporum, is an important disease of pepper in many regions of the world. A phosphate solubilisingTrichodermastrain MHT1134 was selected from 76 isolates from the pepper rhizosphere as a potential biological control agent against wilt disease caused byF. oxysporum. The inhibitory rate of MHT1134 againstF. oxysporumwas 81.80%. MHT1134 was identified asTrichoderma hamatumbased on morphological features, ITS rDNA andtef-1 alpha sequences. It showed antagonistic effects against a number of fungal pathogens, includingPhytophthora capsici,Colletotrichum capsici,Verticillium dahliae,Verticillium albo-atrum,Botryosphaeria dothidea,Pyricularia griseaandPhoma lingam.The fungistatic capability of strain MHT1134 was evaluated, and its sterilised and non-sterilised fermentation broths were effectively suppressed pathogen's hyphal growth, with inhibitory effects reaching 50.71% and 74.01%, respectively. Moreover,T. hamatumMHT1134 controlled pepper wilt at a 60.61% efficiency level, and applications significantly increased plant heights, root lengths, fresh and dry weights of pepper in pot experiments. The field experiments showed that strain MHT1134 inhibited pepper Fusarium wilt, with a control effect that was only slightly less than that of the chemical hymexazol, and significantly increased pepper yield. Thus, MHT1134 is proposed as a potential biocontrol fungus and further studies will focus on its biocontrol mechanisms.