Impacts of Diseases on the Qualitative Characters of Tropical Tasar Silkworm |
The present communication accounts for the relativeimpacts of four different common diseases viz, Sporozoasis (protozoan),Bacteriosis (Bacterial), Virosis (Viral) and Mycosis (Fungal) on thequalitative characters of tasar cocoons of Antheraea mylitta D. during seedcrop (July—August) and commercial crop (Sep.-Oct.) seasons. The results of theexperiment are indicative of the fact that all the four diseases adverselyaffect the qualitative characters of tasar cocoon viz; cocoon wt; shell wt;length of tasar silk filament; non-breakable filament length; filament denierand the percentage of reelability. However, the adverse effect of Sporozoasisas compared to three other diseases has been found to be more significant. Thequalities of the cocoons in relation to four different diseases duringcommercial crop season as compared to seed crop season have been found to berelatively superior, thus account for the seasonal variation. The relativevariation in respect of qualitative characters of cocoons in relation to fourdifferent diseases are presumed due to the diverse nature and mode of action offour different pathogens causing the diseases.