Some Biological Characteristics of Isaria javanica (Frider. & Bally) Samsom & Hywel-Jones Distributing at Pu Mat National Park, Nghe An

Abstract

    Field surveys of entomopathogenic fungi were carried out in Pu Mat National Park from 2011 to 2013. A total of 18 strains of Isaria javanica were collected, isolated and identified of which 6 strains infecting Lepidopteran larvae, 8 strains infecting Hymenopteran adults and 4 strains infecting spider adults. Specimens were found in the leaf litter with 66.67% and on the leaf underside with 33.33%. A white to ash gray powdery layer covers some parts or most of the host body. Conidiophores are vertical single or branching; phialides cylindrical basal part, thin neck, 8.4-14.2x2.2- 2.8 μm in size; conidia fusiform, sometimes cylindrical, smooth-walled, hyaline then turning cream, light gray or ash gray when mature, 4.5-7.4x1.4-1.7 μm in size. Colonies on PDA at 25^oC are relatively fast growing with diameter 23.14 mm after 9 days. The conidia appear on the 3^rd day showing white colourand then turning cream and to light gray or ash gray at maturity.