Morphological characters and efficacy of thirteen entomopathogenic fungi of Aschersonia aleyrodis Webber isolates on whitefly (Bemisia tabaci Gennadius)

Abstract

In the intercropping system between of soybean and citrus plant was known as a triggers of the explosion of whitefly (Bemisia tabaci) and citrus whitefly (Dialeurodes citri) population. These two types of insect pests are in the same order and family which known as an important as vectors for various types of viruses. This study was aimed to identify the morphological characters and efficacy of entomopathogenic fungi that infect B. tabaci and D. citri. Insect cadavers colonized by fungal mycelium were taken from three centers of soybean production in East Java Province (Banyuwangi, Jember, and Pasuruan Regencies). Each insect cadaver from the field was sterilized using 0.5% chlorox solution and then incubated in potato dextrose agar medium. The growing colonies were identified based on morphological characters and then tested by Koch's postulates against B. tabaci. The results of the identification showed that there were Aschersonia aleyrodis Webber fungi obtained with white colony color which then turned into light brown. The size of conidiophores was 39–40×2.1–2.3 µm, conidia 10–11×2.0 µm, optimum temperature 27–30°C, toxic to egg, nymph, and imago, especially isolates from Banyuwangi Regency with mortality reaching 89% within 3–4 days after application. The finding of A. aleyrodis fungal isolates is a new innovation in biological control because both B. tabaci and D. citri are tolerant to synthetic pesticides due to biotype changes.