Beauveria bassiana (Ascomycota: Hypocreales) wound dressing for the control of Euzophera pinguis (Lepidoptera: Pyralidae)

Injury to olive tree trunks and branches because of biotic and abiotic factors, such as pruning and mechanical harvesting, attracts the olive pyralid moth Euzophera pinguis Haworth (Lepidoptera: Pyralidae). This moth has become increasingly important in the Mediterranean region during recent years. The use of an entomopathogenic fungus for wound dressing for pest control is reported for the first time in this study. Beauveria bassiana (Ascomycota: Hypocreales) strain EABb 08/04-Ep was originally obtained from a diseased E. pinguis larva and has shown effective E. pinguis control in an olive crop in Jaén, Andalusia, Spain, under field conditions during the spring and fall of 2008 and 2009 and the spring of 2011. Experimental artificial 30 by 30-mm square wound cages were large enough to allow the E. pinguis females to oviposit. Approximately 80 and 40-60% of the control wounds contained live larvae in the experiments that occurred during the spring and fall, respectively. The B. hassiana wound dressing gave similar results as the chlorpyrifos wound dressing throughout the experiment, with efficacies reaching 80-85% in the spring and 90-95% in the autumn. The B. bassiana fungus was recovered from 60-90% of the wounds at the completion of the experiments and after 60 d of treatment. These data indicate that strain EABb 08/04-Ep applied to the pruning wounds can be an effective tool for the microbial control of E. pinguis in olive crops. Moreover, B. bassiana may be used within integrated pest management strategies to minimize chemicals, depending on the population density of the pyralid moth.