Alteration in the primary metabolites in three different tissues of silkworm, Bombyx mori L. under the influence of a Juvenoid, R۳۹۴

A bivoltine silkworm hybrid, KA x NB۴D۲ was treated with the juvenoid R۳۹۴ (Ethyl-۹ cyclohexyl-۳,۷-dimethyl-۲,۴-nonadienoate) at a dose of ۰.۰۳۹ nl/larva at ۲۴, ۴۸, ۷۲ and ۹۶ h of ۵th instar for silk yield improvement. Treatment specific significant increase was observed in the cocoon and shell weight with no such marked variation in the shell percentage. Notable changes were also seen in traits such as larval duration, larval weight and silk gland weight in the treated silkworm. Total protein, total carbohydrate and total lipid were analyzed in the posterior silk gland (PSG), haemolymph and fat body of fully grown larvae. The result indicated that the content of these primary metabolites varied significantly in the selected tissues depending on the time of juvenoid application. The highest content of protein in the haemolymph and silk gland was in the larvae treated at ۷۲ h whereas the fat body protein content was lowest in the same group. 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کلیدواژه ها:

Bombyx mori ، Fat body ، Haemolymph ، Juvenoid ، R۳۹۴ ، Silkworm