Research article BIOCHEMICAL CHANGES DURING THE PROGRESSIVE INFECTION OF BmIFV IN THE SILKWORM, BOMBYX MORI L.

Among silkworm diseases, Viral diseases are the major and most common during silkworm rearing and cause considerable damage to cocoon production. Viral flacherie in silkworm is caused by the two non- occluded viruses viz., BmIFV and BmDNV. BmIFV causes the highly contagious infectious flacherie disease in silkworm. In our earlier studies susceptible and tolerant silkworm breeds against BmIFV were identified from the Indian Germ plasm stock. In the present study, the changes in major organic constituent's viz., total protein, total carbohydrate and total lipid content during the progressive infection of BmIFV in a susceptible breed, CSR2 was studied. As the larval age increases, there was a consistent increase in the level of organic constituents viz., total protein, total carbohydrates and total lipids in both control and treated batches but the level of increase in treated batches were markedly less when compared to the respective control batches. During the progressive infection of BmIFV, there was a significant decrease in total protein and total carbohydrate contents and significant increase in total lipid content in the haemolymph and mid gut tissues when compared with control batches. These changes were reflected in the expression of discernible morphological changes, disease symptoms and larval mortality.