Entomopathogenic Fungi (Ascomycota: Hypocreales) as Natural Antagonists of the Pine Processionary Moth Thaumetopoea pityocampa (Denis & Schiffermuller, 1775) (Lepidoptera: Notodontidae) in Bulgaria

摘要

Thaumetopoea pityocampa, a moth naturally distributed in pine ecosystems of Mediterranean region, is considered the most dangerous defoliator in Bulgarian pine forests. Caterpillars of this species also represent a health hazard because their hairs, which contain an urticating protein - thaumetopoein, are responsible for painful skin irritations, rashes and allergic reactions in some people. Therefore, T. pityocampa is not only a serious forest pest, but also a public health problem. Populations of the moth are regulated by a complex of natural enemies. There is only limited information about a parasitic activity of entomopathogenic fungi. These fungi are natural antagonists of insects helping to control of host population and prevention of outbreaks formation. A goal of the present study was to identify species of entomopathogenic fungi in natural populations of T. pityocampa in Bulgaria. During the study, 908 larvae and pupae were collected from two sites (Fotinovo and Kandilka villages) in the south-eastern Rhodopes. In laboratory conditions, 147 larvae or pupae showing characteristic symptoms of mycoses were observed and on 27 of them in vitro isolates were obtained. The cultures were microscopically identified and subsequently analysed by a sequencing study of the internal transcribed region of rDNA and a partial sequence of TEF1-alpha gene. Altogether, two Beauveria species (B. pseudobassiana - 7 isolates and B. varroae - 6 isolates) and Purpureocillium lilacinum (14 isolates) were identified. The three entomopathogens are reported from T. pityocampa for the first time.