The Auto-infection Trap with the Native Entomopathogenic Fungus, Beauveria Bassiana for Management of Coffee Berry Borer (Stephanoderes Hampei Ferrari) in the Northwest Region of Vietnam

Abstract

Among important crops in Vietnam, we have to mention the coffee crop as the main cultivated crop in northwest area of the country, then we have to deal with the negative factor, or insect, coffee berry borer (CBB), which cause losses and damages for farmers with negatively significant impact. In previous studies, we isolated and identified five Beauveria bassiana strains of entomopathogenic fungus that damaged on coffee berry borer in local coffee fields of Son La province, Vietnam. The objective of this study continued to choose one of them for management CBB by autoinoculation trap. The result show that the virulence against CBB of the Bb5(MCB1) strain was highest (71.3 % confirmed mortality). Although 62.5% of CBB females that exposed to the Bb5(MCB1) fungus product with an average of 0,47 x 1012 conidia.gram-1 were able to penetrate the coffee berry exocarp, only 3.7% reached the endosperm. An autoinoculation trap containing the entomopathogenic fungus Bb was designed for the management of the CBB (trap TBU-AIT). Traps TBU-AIT baited with methanol and ethanol (1:1 ratio) mixtures at 868 mg day-1 attracted more insects than those traps baited at 452, 715 and 1050 mg day-1. We found a statistically-significant difference in average confirmed mortalities by fungus and by different field conditions in the period between 0 - 63 days setting traps TBU-AIT. Altogether, these results and relatively low production costs these auto-infection system can be recommended for integrated pest management on coffee auto-infection trap.