Biological and technological effects of mulberry varieties and nutritional additives on silkworm Bombyx mori development

Abstract

The efficiency of two varieties of mulberry leaves, Morus alba var. Kokuso-27 and Morus indica var. Kanva-2, was investigated and compared with Morus alba var. Balady (native), the common local variety in Egypt. Mulberry varieties were offered to silkworm larvae in two, three or four feeds per day. Rearing with Kokuso-27 leaves, especially with the feeding schedule of four feeds per day, exhibited significantly shorter larval duration, lower larval mortality rate and increased larval fitness, cocooning percentage, fecundity and hatchability. It also yielded higher cocoon weight, silk content ratio and silk filament size. Kanva-2 showed the lowest performance. Kokuso-27 leaves were enriched with nutritional additives such as vitamins C (1%) and B (0.2%), and three kinds of honey (from clover, cotton and citrus, 50%) and offered once per day. Significant enhancement occurred in all tested groups compared with the control, especially for vitamin C and clover and citrus honey, in most variables except larval duration and fitness.

Keywords: Morus alba var. Kokuso-27, Morus indica var. Kanva-2, Morus alba native, Vitamin C, Vitamin B, Bee-honey.

Egyptian Journal of Biology Vol. 10 2008: pp. 1-10