Effects of entomopathogenic fungi (EPFs) and cropping systems on parasitoids of fall armyworm (Spodoptera frugiperda) on maize in eastern central, Tanzania

Abstract

ABSTRACTFall armyworm (FAW), Spodoptera frugiperda is a key pest of maize in Africa including Tanzania. Field trials were conducted to determine the incidence of species of parasitoids and their rate of parasitism on selected IPM treatments. The experiment was conducted at crop Museum of Sokoine University of Agriculture, Morogoro, Tanzania for two cropping seasons and arranged in a split – split-plot design with three replicates. The treatment combinations were push–pull without application of pesticides, push–pull and Beauveria bassiana, push–pull and Metarhizium anisopliae sensu lato, push–pull and flubendamide, cowpea + maize without application of pesticides, and cowpea + maize and Beauveria bassiana. Others were cowpea + maize and Metarhizium anisopliae sensu lato, cowpea + maize and flubendamide, maize sole crop without application of pesticides, maize sole and Beauveria bassiana, maize sole and Metarhizium anisopliae, and maize sole and flubendamide. The results showed that one species of egg-larva parasitoids (Chelonus bifoveolatus) and two species of larva parasitoids (Coccygidium luteum and Cotesia sp.) were recovered from the sampled fall armyworm eggs and larvae. The percentage of parasitism of C. bifoveolatus and C. luteum differed significantly among intercropping systems (p < .001). The results also showed that the percentage of larval parasitism of Cotesia sp. differed significantly (p < .001) among intercropping systems only. These results confirm biological control of fall armyworm through the conservation of natural enemies in Tanzania.