STUDY OF QUANTITATIVE CHARACTERS BY SILKWORM LARVAE AFTER TOPICAL APPLICATION OF METHOPRENE AND

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. In the cocoons and silk from 5th instar B. mori treated with selected doses of methoprene and fenoxycarb. Quantitative parameters like larval weight, silk gland weight, cocoon weight, cocoon shell weight, were determined. Methoprene and fenoxycarb influenced positively the duration of the fifth instar and the weight gain of the insects. Comparatively to the control lot, the increment on silk production was approximately 24 % by the use of 1ng methoprene