Effect of major pollutants from motor vehicles on mulberry leaves and food ingestion, assimilation conservation efficiency of mulberry silkworm, Bombyx mori Linn.

Abstract

The present investigation was carried out to ascertain the possible effect of feeding the silkworm, Bombyx mori L. with motor vehicles major pollutant like volatile organic compound, nitrogen oxides, carbon monoxide, sulfur dioxide and green gases polluted mulberry leaves on the food consumption, assimilation and conversion efficiency using silkworm hybrids, SH6 × NB4D2, CSR2 × CSR4, DUN22 × DUN6 and CSR double hybrid in relation to the road pollutant from the National Highway at all over, India. The roads generate vast amount of pollutant which got deposited on the mulberry leaves. Silkworm is essentially monophagous insect feeds solely on mulberry leaves. Impact on the silkworm nutritional indices food consumption, assimilation and conversion efficiency were assessed by rearing the silkworm larvae on air polluted mulberry leaves besides the amount of pollutant deposition on the mulberry leaves was also measured. The food consumption, assimilation and conversion efficiency of the silkworm larvae got significantly reduced in both the IVth as well as in the Vth instar larvae, when they were fed with extreme polluted mulberry leaves as compared to those larvae which were fed with low polluted mulberry leaves. But the effect was more pronounced in the Vth instar as larvae utilize maximum amount of feed in the Vth instar. The reduced conversion efficiency culminated in the decreased average larval weight and average larval weight gain of the silkworm larvae and cocoon production. All the silkworm hybrids register a marked affect when they were fed with extreme polluted mulberry leaves, but CSR2 × CSR4 hybrid was affected most with the CSR double hybrid least affected.