Preliminary experiments to control the silverleaf whitefly with electrostatic spraying of a mycoinsecticide

Abstract

The electrostatic application of a mycoinsecticide, Paecilomyces fumosoroseus, was tested for controlling the infestation of the silverleaf whitefly, Bemisia argentifolii, to tomato plants in greenhouses. Electrostatic application had no impact on fungal viability, measured as colony-forming units (cfu), and resulted in good fungal deposition (cfu/cm2 of leaf surface) on both the adaxial and abaxial surfaces of leaves. The adaxial/abaxial surface ratio (1.8) was comparatively low, suggesting that the electrostatic application of mycoinsecticides is potentially useful for controlling greenhouse pests. However, experiments for controlling the whitefly produced unsatisfactory results, with larval mortalities of 48.1% on d 11 after the first electrostatic application of the mycoinsecticide and 23.9 and 8.1% on d 7 and 19 after the second application, respectively. It is likely that the low larval mortalities were caused by environmental conditions not conducive to fungal infection.