DETECTION OFNOSEMA BOMBYCIS NAEGELI INFECTION IN SILKWORM BOMBYXMORI L. B Y DIFFERENT STAINING TECHNIQUES

摘要

The protozoan disease of silkworm, Bombyx mori, commonly known as "Pebrine" is caused by the microsporidian, Nosema bonibycis Naegeli. The disease is transmitted transovarially to the progeny eggs (Han and Watanabe, 1988), besides through per-oral infection by feeding contaminated leaf. The disease causes heavy mortality of silkworm larvae during rearing which results in crop loss to the rearers. The difficulty of detection of the pathogen is a constraint for the management of the disease as the visibility and clarity of the spores of the pathogen get obstructed by the presence of tissue debris, fat globules and moth scales, in the homogenate of the infected moth. Although several studies have been conducted for the detection of the disease such as,Iso-density equilibrium centrifugation technique (Sato and Watanabe, 1980), fluorescent antibody techniques (Sato et al., 1981), antibody sensitized latex (Hayashiya and Ayuzawa, 1987; Watanabe,1987) and agglutination tests (Sengupta et al., 1993), these techniques are complex, expensive, involving long time procedures and technical skills. Thus as a part of the requirement to develop a technique by which spores get easily detected in the homogenate, some staining techniques were developed for the easy detection of the spores of N. bonibycis.