ABSTRACT

Entomopathogenic fungi are widely distributed and well described within the fungal kingdom. Different species of fungi belonging to the Genus Cordyceps are well known pest control agents. This study reports the isolation, characterisation as well as virulence of six fungal isolates belonging to three different species of Cordyceps genus including three C. farinosa isolates; two C. fumosorosea isolates; and one C. tenuipes isolate against P. xylostella. The newly identified strains proved pathogenic to P. xylostella under laboratory conditions. In addition, the C. fumosorosea isolate SCFU-1 was virulent against eggs, 1st, 2nd, 3rd, 4th instar larvae and pupae of P. xylostella having LC₅₀ values of 1.27 × 10⁹, 2.78 × 10⁶, 2.59 × 10⁶, 2.87 × 10⁶, 1.22 × 10⁷, and 1.71 × 10⁹ conidia/mL, respectively 7 days post application. The newly isolated strains can be developed as potential biopesticide for P. xylostella although extensive field bioassays as well as development of proper formulation is still required.

摘要

致病性真菌在真菌界内广泛分布并得到了很好的描述。属于虫草属的真菌的不同种类是众所周知的害虫防治剂。这项研究报告的分离，鉴定以及属于三个不同的物种六个真菌分离致病虫草属包括三名C. farinosa株; 两种C. fumosorosea分离株; 和一种对虾小球藻分离株。新鉴定的菌株在实验室条件下被证明对小菜蛾有致病性。此外，C。fumosorosea分离SCFU-1针对蛋，第一，第二，第三，第四龄幼虫和蛹剧毒小菜蛾具有LC _50个的1.27×10值⁹，2.78×10 ⁶，2.59×10 ⁶，2.87×10 ⁶，1.22施用后7天分别为×10 ⁷和1.71×10 ⁹分生孢子/ mL。新分离出的菌株可以开发为小菜蛾的潜在生物农药，尽管仍然需要广泛的现场生物测定以及正确配方的开发。