Evaluation of the Entomopathogenic Potential of Beauveria bassiana , Metarhizium anisopliae and Isaria fumosorosea for Management of Cosmopolites sordidus Germar (Coleoptera: Curculionidae)

The banana weevil (BW), Cosmopolites sordidus , is the main coleopteran pest of banana, causing up to 100% yield loss. In this study, we screened 20 isolates of entomopathogenic fungi (EPF) for the management of BW. In the lab, eight Beauveria bassiana isolates caused >50% mortality of the adult BW, whereas Metarhizium anisopliae and Isaria fumosorosea isolates were less pathogenic. B. bassiana isolates ICIPE 648, ICIPE 660 and ICIPE 273 were the most pathogenic, killing ≥80% of adult BW. B. bassiana isolate ICIPE 622 yielded the highest spores per BW cadaver (1.84 × 10 8 spores), followed by ICIPE 660, ICIPE 273 and ICIPE 648—1.17 × 10 8 , 3.8 × 10 7 and 3.6 × 10 7 spores, respectively. ICIPE 273 had the shortest LT 50 (5.3 days) followed by ICIPE 648 (9.8 days) and 660 (11.1 days). Similarly, the LC 50 values for the three isolates were 5.18 × 10 7 , 5.49 × 10 7 and 5.2 × 10 7 spores mL −1 , respectively. In the field, ICIPE 273 and ICIPE 648 had the highest (31.3%) and lowest (20.8%) pathogenicity, respectively. This study indicates that the B. bassiana isolates ICIPE 273, ICIPE 648 and ICIPE 660 are potential candidates for the environmentally sustainable management of BW.