Efficacy of Metarhizium anisopliae to control adults of Haplaxius crudus (Van Duzee) (Hemiptera: Cixiidae), vector of lethal wilt disease of oil palm in Colombia

Abstract

Haplaxius crudus (Van Duzee) is the vector of the pathogen that causes Lethal wilt disease, one of the most important diseases of oil palm in Colombia. Currently, H. crudus populations are controlled with calendar applications of chemical insecticides, however, their efficacy and effect on the ecosystem are unknown. The use of entomopathogenic fungi such as Metarhizium anisopliae may be an alternative to control this pest in the crop since this fungus has been isolated from adults of H. crudus found in oil palm plantations. Therefore, the objective of this study was to evaluate the efficacy of 10 native strains of M. anisopliae to control adults of H. crudus under laboratory and field conditions. The strain CPMa1309 was selected because it caused mortalities in H. crudus adults greater than 90% at a dose of 1 × 1012 conidia/ha, as well as for its capacity to grow rapidly and produce large numbers of conidia on an artificial medium (4.95 × 107 conidia/ml). These results show the possibility of incorporating the fungus M. anisopliae CPMa1309 in an integrated management program for the biological control of H. crudus but it is important to validate its effectiveness under different agro-ecological conditions, where oil palm grows in Colombia.