Studies on Symptomological and Economic Parameters of Silk Cocoons of Bombyx Mori Inoculated with Beauveria Bassiana (Bals.) Vuill.

Abstract

The muscardine disease in the larval instars of silkworm is caused by fungus, Beauveria bassiana (Bals)
Vuill. The Beauveria bassiana (Bals) Vuill is one of the most destructive pathogen of silkworm Bombyx
mori L and it is common in all sericulture zones of the world. The fungal disease is common during
winter and rainy seasons. White muscardine was the first disease described in insects caused by a
microorganism. This fungus was named eventually Beauveria bassiana in honor of Agostino Bassi,
sometimes called de Lodi (25 September 1773 – 8 February 1856), Italian entomologist, botanist and
bacteriologist recognized as the “Father of Insect Pathology”. Beauveria bassiana infection influenced
the growth and development of silkworm larvae and ultimately the economical cocoon characters like
matured larval weight, cocoon weight, shell weight, shell percentage, filament length, non-breakable
filament length, number of breaks and denier. Significant reduction of matured larval weight (2.08 g),
cocoon weight (0.72 g), shell weight (0.09 g), shell ratio (12.80%), filament length (478.9 m), nonbreakable
filament length (120.8 m) and more number of breaks (4.1) and higher denier (2.62 d) was
recorded in the experimental silkworm compared to control.