Influence of the diterpenoids (Retinol and Phytol) (Race: PM x CSR2) on the cocoon and silk parameters in silkworm, Bombyx mori (L) (Race: PM x CSR2)

Topical application of ten microliters of one milligram per liter strength acetone solution of retinol phytol to the individual fifth instar larvae of multivoltine cross breed race of silkworm, Bombyx mori (L) (PM x CSR2) at 48, 54, 60 and 66 hours after the fourth moult was found variously reflected into prolongation of larval age (14 – 39 % for retinol treated groups and 17 – 42 % for phytol treated groups); improvement in the tissue somatic index (TSI) of silk glands (3.053 – 3.343 for retinol treated groups and 3.070 – 3.092 % for phytol treated groups); cocoon shell ratio (2.790 – 3.177 for retinol treated groups and 2.693 – 3.629 for phytol treated groups) and denier scale of silk filament (p< 0.01). Retinol and phytol, thus chiefly lengthening the larval age in silkworm, Bombyx mori (L). The synergistic activity of diterpenoids in the present attempt is hypothesized to be due to changes in the membrane fluidity, interference with membrane bound signaling proteins and cell cycle arrest. Efficient utilization of diterpenoids like, retinol and phytol, through acetone solvent for topical application to the fifth in stared larvae of silkworm, Bombyx mori (L) may open a new biotechnological avenue in the sericulture industries.