HISTO-PATHOLOGICAL INVESTIGATIONS IN THE MIDDLE REGION OF SILKGLAND IN BOMBYX MORI L. DURING THE DEVELOPMENT OF BEAUVERIA BASSIANA (BALS) VUILL
The investigation mainly focused to examine the mutilation caused by the fungal pathogen Beauveria bassiana during its growth and development in 5th instar silkworm larvae using histopathological indices. Day to day histopathological analysis of the middle region of the silkgland during the development of fungal pathogen in fifth instar silkworm larvae revealed no significant changes in the first two days of the post inoculation. On the third of the instar mycelia of Beauveria bassiana was noticed in the tunica propria the outermost layer of the silk gland and on the 4th day of inoculation, secretory cells in the glandular layer filled with mycelia. Shrinkage of silkgland tissue was observed on 5th and 6th day of post - inoculation of Beauveria bassiana. The histopathological study revealed extensive hyphal growth with a subsequent melanization reaction and shrinkage of the tissue in the silkgland