Studies on pathogenicity and infection process against Spilarctia obliqua (Walker), genetic variability, compatibility with chemical pesticides and mass multiplication of Beauveria bassiana (Balsamo) Vuillemin
Loading...
Date
2008-01
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand)
Abstract
The studies on pathogenicity of different isolates of white muscardine fungus, Beauveria bassiana (Balsamo) Vuillemin against larvae of Bihar hairy caterpillar, Spilarctia obliqua (Walker) of different age groups, its mass multiplication on different growth media, compatibility with different chemical pesticides, histopathological studies of the mycosed test insect and genetic variability among different strains of B. bassiana by using Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats Polymeric Chain Reaction (ISSR-PCR) based molecular markers were conducted. In the bioefficacy evaluation, five isolates of B. bassiana were found to be pathogenic against three different age groups of larva of S. obliqua, whereas three isolates showed non pathogenicity against the test insects. On the basis of pathogenicity test, it was observed that Pantnagar isolate was more virulent against the test insects over others isolate. Culturing of B. bassiana on different grain based media indicated superiority of pulse grain over cereals in terms of biomass and conidia production. Among pulse grains, pea and chickpea were superior in biomass and conidia production of B. bassiana. Among insecticides spinosad and imidacloprid were found to be most suitable with B. bassiana with regard to mycelial growth and among fungicides thiram, captan and mancozeb were found to be compatible while contaf, bavistin and tilt were found to be incompatible with B. bassiana in the same term. Histopathological study revealed that hyphal bodies of the fungus generally penetrates through integument and invades in the hypodermal region of the body wall. At molecular level genetic diversity among eight isolates of B. bassiana were assessed based on RAPD and ISSR (PCR based molecular markers). Maximum polymorphism was revealed by RAPD (99.16%) followed by ISSR (98.25%).
Description
Keywords
null