author(s)
DD Barsagade and HM Meshram

abstract
Tropical tasar silkworm Antheraea mylitta is economically important insect and it produced famous tasar silk commonly known as ‘Kosa Silk’. The Indian tropical tasar silkworm is affected by disease flacherie (bacteriosis) caused by bacteria, which accounts considerable loss of 10-15 % silk cocoon production. In the present investigation histopathological effect of diseases causing bacteria in tasar silkworm, Antheraea mylitta has been studied. The bacteria from diseased rectal protrusion were isolated on specific growth media, identified as Bacillus subtilis and its effects on midgut and silk gland of tasar silkworm were investigated. During early infection, midgut epithelial cell size increased with vacuole formation. During late stage of infection, mid gut columnar epithelium cells showed hypertrophy and blabbing of plasma membrane, disruption of microvilli, vacuolization and permanent foremost nuclear changes to necrosis. The silk gland of diseased larvae showed cyto-morphological changes with reduced cell size and vacuole formation in early infection. The progressive disintegration of cytoplasmic organelles occurs with advancement of diseased in silk gland.