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Attraction of adult banana weevil, Cosmopolites sordidus to volatiles from banana pseudostem tissue and the synthetic pheromone Cosmolure+ presented singly or in combination, was studied in the laboratory and in the field. Olfactometric studies in the laboratory showed that 50 g of fermented banana pseudostem tissue was as attractive as pheromone but more attractive than 50 g of fresh pseudostem tissue. In the laboratory, volatiles from pseudostem tissue had an additive effect on attraction of weevils to the pheromone but the effect was not significant in the field. Field trials, however, showed that attractiveness to weevils was positively correlated with the amount of fermented tissue added to the pheromone. The results indicate that fresh or fermented pseudostem tissue may enhance pheromone trap catches but the effect was not large enough to warrant their deployment for the optimisation of the infochemical-based trapping system for the management of C. sordidus. [ABSTRACT FROM AUTHOR]

Candidate strains of Beauveria bassiana were identified for use in integrated pest management of the banana weevil Cosmopolites sordidus. Horizontal field transmission of B. bassiana between banana weevils using different delivery systems, including aggregation pheromones, was investigated. We observed that infected weevils could transmit the fungal pathogen to healthy individuals. Most dead weevils (52%) due to B. bassiana infection were found at the base of banana plants in the leaf sheath or in the soil near banana plants. Significantly more weevils died from the pathogen in plots where B. bassiana was applied in combination with the pheromone than where it was applied alone. Our data demonstrate that C. sordidus aggregation pheromone can be a valuable tool to enhance the dissemination of B. bassiana for the control of C. sordidus. [ABSTRACT FROM AUTHOR]

Studies were conducted in Uganda to evaluate the influence of distance, environmental factors, trap location and trap type on catches of Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) in pheromone-baited traps. Marked weevils were released at recorded locations within plots. Trap efficiency was low and decreased with distance from the pheromone trap. When weevils were released in close vicinity to the trap, significantly more weevils were recaptured from 0.5 m compared to those recaptured from 4 m within 30 days of trap placement. Relative humidity showed a significant positive relationship to C. sordidus catches, while wind speed, temperature and rainfall had no effect. Covering pheromone-baited traps with banana leaves increased capture rates. In one experiment, more weevils were captured in pheromone-baited traps placed in alleys than at the base of mats, while no differences were found in the second. This study provides information on how various factors influence the effectiveness of pheromone-baited traps that will assist in designing a pheromone-based mass trapping strategy for the control of C. sordidus . [ABSTRACT FROM AUTHOR]