Lecanicillium attenuatum isolates affecting the invasive cypress aphid (Cinara cupressi) in Chile

Abstract

The cypress aphid (Cinara cupressi) is listed among the hundred most important invasive pests in the world. In Chile, it was first detected in 2003 and currently is present throughout the country. In the course of a survey of their natural enemies in Chile, three strains of entomopathogenic fungi were isolated. The isolates were identified and tested against the aphid in laboratory experiments. Two further entomopathogenic fungi (ARSEF 5126 and 5128), formulated in the mycoinsecticides Vertalec® and Mycotal®, were used as reference strains. The three Chilean isolates were identified genomically as Lecanicillium attenuatum and were pathogenic to third-instar nymphs. The isolate ARSEF 13279 yielded the lowest overall lethal concentration (LC50), 3 × 105 conidia ml−1 at four days post-inoculation, and the shortest lethal time (LT50), 3.7 days after inoculation with 106 conidia ml−1. The results indicate that the isolates have considerable potential as microbial control agents of the invasive cypress aphid.