The silkworms are susceptible to various diseases and attacked by pests and parasites. The diseases and pests together cause considerable damage to the silk industry. The diseases are caused by biological, chemical, nutritional and environmental factors. The biological factors causing diseases are viruses, bacteria, fungi, protozoa and arthropods, all of which are parasites; and all except arthropods are infectious. Agro-chemicals, pyrethroids, exhaust gases from automobiles and factories, smoke, residue from disinfectants, etc. are among the chemical agents causing diseases. The chemical...