Vol. 2, Issue 6 (2017)
Development and silk production by silkworm larvae after topical application of fenoxycarb
Author(s): Neha Singh Sisodia, Santosh Gaherwal
Abstract: Juvenile hormone analogues have been tested as insect growth regulators in silkworm (Bombyx mori), seeking an increment of silk production. These chemical products, when applied in small or moderate rates, promote the extension of the last larval instar. To understand the physiologic consequences on silk production by the silkworm strain CSR2 × CSR4.The application of fenoxycarb, a juvenile hormone analogue was performed to evaluate its effects on larval development and silk production. Fenoxycarb was topically applied 48h after the fourth larval ecdysis, on the dorsal integument of the 2nd thoracic segment of the insects,between 1 and 1.5 µg fenoxycarb influenced positively the duration of the fifth instar andthe weight gain of the insects. The application of 1µg fenoxycarb resulted in the heaviest silkglands, cocoons, shell cocoons and pupae weights. Comparatively to the control, the increment on silk production by the use of 1µg fenoxycarb was more accentuated than the corresponding negative effects on the cocooning rate.