Influence of the topical application acetone solution of Vitamin A (Retinol) to the fifth instar larvae of the silkworm, Bombyx mori (L) (Race: PM x CSR2) on the economic parameters

Abstract

The attempt concerned with efficient topical application of acetone solution of Vitamin A (retinol) to the fifth instar larvae of multivoltine silkworm, Bombyx mori (L) (Race: PM x CSR2) and assessment of economic parameters. The experimentatio was carried at laboratory level. The ten microliters of one milligram per liter strength acetone solution of retinol was topically applied to the individual fifth instar larvae of multivoltine cross breed race of silkworm, Bombyx mori ( L ) ( PM x CSR2) variously at 48, 54, 60 and 66 hours after the fourth moult. Topical application of acetone solution of retinol was found variously reflected into prolongation of larval age (14 39 %); improvement in the tissue somatic index (TSI) of silk glands (3.06 3.343); cocoon shell ratio (2.790 3.177) and denier scale of silk filament (p< 0.01). Topical application of acetone solution of retinol, thus chiefly lengthen the larval age in silkworm, Bombyx mori (L). Time required for eating and amount of mulberry leaves eaten had both been increased and they were practically reflected into the improvement in the quality of cocoon and the silk filament. Diterpenoid nature of retinol and delay in the spinning among the larvae, recipient of retinol in the attempt indicate the possibility of insect juvenoid activity of retinol in silkworm, Bombyx mori (L). Efficient utilization of retinol, the diterpenoid through acetone solvent for topical application to the fifth instared larvae of silkworm, Bombyx mori (L) may open a new biotechnological avenue in the sericulture industries.