Biocontrol of Planococcus citri (Hemiptera: Pseudococcidae) by Lecanicillium longisporum and Lecanicillium lecanii under laboratory and greenhouse conditions

Abstract

Much effort has been focused on the development of microbial biopesticides composed of entomopathogenic fungi as alternatives to synthetic insecticides for pest management programs. The citrus mealybug, Planococcus citri Risso (Hemiptera: Pseudococcidae), is an important pest in greenhouses and on citrus plants globally. The current study isolated and characterized two species of entomopathogenic fungi, Lecanicillium longisporum (Petch) Zare & W. Gams and Lecanicillium lecanii (Zimmere). Their virulence at the second nymph and adult stages of P. citri were documented using mycosis with scanning electron microscopy. L. lecanii was found to be more effective at different citrus mealybug growth stages. Nymphal P. citri were more susceptible than adults to fungal infection. Susceptibility at all stages was dose dependent. The results of laboratory trials used for greenhouse tests. In a comparison of wheat, beet pulp paddy rice and rice bran as substrates for solid substrate fermentation, wheat produced the most conidia for the L. lecanii. For L. longisporum, however, was the most appropriate media. The results of this study indicate that the entomopathogenic fungi L. longisporum and L. lecanii are potentially useful biological control agents for the citrus mealybug.