PHOTOSENSITIVE EFFECT OF THE BIOCHEMICAL AND ECONOMIC TRAITS OF Bombyx mori L.

Abstract

The silkworm is by nature very delicate and sensitive to environmental conditions. The ecological factors, chiefly temperature, humidity and light during rearing show significant effect on growth larvae and finally cocoon crop quality. Silkworms are photosensitive and they have a tendency to crawl towards dim light. They do not like either strong light or complete darkness. In this way, based on various exposures of light on the effect of biochemical content and economic traits of silkworm were recorded. Biochemical content such as protein is highly essential for insects. The intracellular transport of the silk protein is dependent on hydrophobicity or hydrophilicity of the amino acid residues of the heavy and light chain of the silk protein and the haemolymph is the only extracellular fluid of insects with diverse functions and serves as reservoir for the products required for every physiological activity of the insect body, thus changes in the composition of haemolymph reflect the physiological and biochemical transformations taking place in the insect tissue. In this way of study, effect of light on biochemical content such as protein and carbohydrate of haemolyph and silk gland are significantly increased. The protein content was high in the haemolymph (17.48%) when the larvae exposed to 5 watt light and silk gland (66.67%) in 3 watt exposure group but fat body (44.33 %) when the larvae exposed to 8 watt. The carbohydrate content of haemolymph (35.54 %), silk gland (12.85%) and fat body (57.26 %) were significantly increased in 3 watt exposure group. In this findings, biochemical content had direct relation to economic traits of B. mori. The cocoon characters such as cocoon weight (28.42 per cent), pupal weight (20.9 per cent), shell weight (71 per cent) and shell ratio (33.48 per cent) were significantly increased in the 3 watt exposed group.