Compatibility of Metarhizium anisopliae (Ascomycota: Hypocreales) with selective insecticides against Plutella xylostella (Lepidoptera: Plutellidae)

The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is one of the most important cruciferous pests, severe economic damage. Microbial control is based on the reasoned use of pathogens to manage pest population levels. Metarhizium anisopliae (Ascomycota: Hypocreales) is one of the facultative insect pathogens; it is a good choice for that purpose. Conidia survival may be affected by several environmental factors or through chemical pesticides used to control pests. In this research, the efficiency of M. anisopliae IRN.1, when used alone or in combination with sub-lethal doses of lufenuron, flubendiamide and indoxacarb, against P. xylostella was studied. The effect of pesticides on the vegetative growth, conidial germination and fungus sporulation was then tested. The results indicated that the compatible formulation with M. anisopliae was indoxacarb. Further median lethal time (LT50) of the fungi combination with the sub-lethal concentration of indoxacarb was less than that of other treatments. The combined use of fungal and indoxacarb could be, thus, used simultaneously in the integrated management of P. xylostella.