EFFICACY OF WILD PLANT IN COMBINATION WITH MICROBIAL ANTAGONISTS FOR THE CONTROL OF ROOT ROT FUNGI ON MUNGBEAN AND COWPEA

摘要

Fusarium oxysporum f. sp. niveum (FON), a soil-borne pathogen of watermelon (Citrullus lanatus), can causesubstantial production losses worldwide. In this study, plate culture and PCR-denaturing gradient gelelectrophoresis (DGGE) methods were used to evaluate the effects of inoculation of Fusarium oxysporum f.sp.niveum on rhizosphere microbial communities of different watermelon cultivars to FON. Two methods indicatedthat the effects of watermelon rhizosphere microbial community of different resistance cultivars to FON weremuch different. Populations of culturable bacteria and actinomycetes in the rhizosphere of susceptible watermeloncultivar were significantly lower than in the resistant cultivar after inoculation (P0.05), but the opposite resultwas observed for fungi. Principal component analysis of bacterial and fungal community structure also showedthat the cultivar of FON-inoculated soil treatment were separated from the non-inoculated controls afterinoculation, and there was clear discrimination between the susceptible cultivars and the resistant cultivars.Sequence analysis of specific bands from DGGE profiles showed that specific rhizosphere bacterial and fungalgroups differed between watermelon cultivars after inoculation . Both methods demonstrated that differentresistant watermelon cultivars occupied different rhizosphere microbial communities, and and disease suppressionmight be correlated with high microbial diversity. F. oxysporum f. sp. Niveum alters the structure and functionaldiversity of microbial communities associated with watermelon rhizosphere.