Pathogenicity of Beauveria bassiana (Deuteromycotina: Hyphomycetes) to Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) insect pest of store maize

Abstract

Pathogenicity, mortality and lethal time of Beauveria bassiana (Bals.) Vuillemin on maize weevil, Sitophilus zeamais (Motsch.) (Coleoptera: Curculionidae) was evaluated using concentrations of 1 x 106, 1 x 107, 1 x 108 and 1 x 109 conidias/ml. The study was conducted at the Entomology Laboratory of the Magdalena University (Colombia) (temperature de 25±1ºC; relative humidity 90±2 %; and photoperiod = 1 2:12) .The fungus was isolate from Leptopharsa gibbicarina (Hemiptera: Tingidae), insect pest of oil palm. Adults of the S. zeamais were obtained from a laboratory mass rearing. The experiment was organized in a complete randomized design with four replications. These insects were exposed to the fungus using four concentrations of conidias/ml. The mortality mean was 98,37 0% for all concentrations. There were significant differences (P ≥ 0,05) among concentration and control. The minor Mean lethal time was to concentrations 1x106 conidia/ml. Results show efficient control