EFFECT OF CERTAIN FOOD ADDITIVES ON REPRODUCTIVE POTENTIAL AND SILK PRODUCTION IN MULBERRY SILKWORM, Bombyx mori

Abstract

The effect of treating mulberry leaves with different food additives i.e., Ascorbic acid, Royal jelly, Bee pollen grains, Algae include Spirulina platensis, Chlorella vulgaris and Scenedesmus sp. on certain biological aspects and silk production of Bombyx mori L. were studied. From the beginning of the fourth instar until the end of fifth instar, larvae were fed on mulberry leaves treated with these different types of food additives once a day and the other daily meals (2-3 meals) with untreated leaves. The obtained results revealed that addition of the three concentrations of ascorbic acid (1, 2 and 3%) to mulberry leaves gave positive results on both biological aspects and silk production. The highest weights of the fourth and fifth larval instars, the shortest duration, the heaviest pupal weight, the maximum number of eggs/female, the heaviest and longest silk gland, the heaviest fresh cocoon, cocoon shell and longest silk filament were obtained after feeding the larvae on mulberry leaves supplemented with 1% ascorbic acid as compared with the other concentrations. Royal jelly treatments also gave the same trend of results on both biological aspects and silk production. Royal jelly at 1.0% gave the best results followed by 0.5 and 1.5%. Also the best results were detected on the biological aspects and silk production when larvae were fed on mulberry leaves treated with 1.0% of bee pollen grains as compared with 0.5 and 1.5%. Results indicated that an addition of two concentrations of the three tested algae to mulberry leaves gave variable results depending on the algae species and its concentration. Supplemented mulberry leaves with 12.50 mg/10 ml distilled water of both S. platensis and C. vulgaris caused the positive effects on the biological aspects and silk production. The same trend was obtained at 18.75 mg/10 ml distilled water of Scenedesmus sp. Keywords: Mulberry, Silkworm, Bombyx mori L., Biological aspects, Silk production, Ascorbic acid, Royal jelly, Bee pollen grains, Algae, Spirulina platensis, Chlorella vulgaris, Scenedesmus sp.