P.G. Department of Zoology, Loyola College, Chennai-600 034, Tamil Nadu (India).
Protein concentration varied in the muscle and gonads of the water bug, Diplonychus indicus Venk. & Rao, based on their size, sex and reproductive activity. Availability of food highly influenced the reproductive strategy of the insects. Under well-fed condition, male bugs showed 63 and 15.2% increase in the amount of protein present in the muscle and testis, respectively. Females showed 32 and 22% increase of protein in their muscle and ovary. Under starvation, the amount of protein in the muscle and gonads of both the sexes decreased drastically. Protein decrease was 7.4 and 14% in the muscle and testis of the male, respectively. In the female, the respective decrease was 7.6 and 10.03% protein in the muscle and ovary. Since the maturation of gonads need large amount of protein, thoracic muscles of the insects of the pre reproductive phase contain only small amount of protein. During the reproductive phase, the male indulges in enforced copulation so that thoracic muscles contain higher amount of protein. After copulation, the females store the sperms in their spermatheca temporarily. Since the spermatozoan itself is a protein, the gonads of the females contain more protein than the muscle. In the post-reproductive phase, the amount of protein present in the muscle and gonads of both the sexes decreased slowly. In general, females are more active than the males, resulting in more protein in the muscle and gonads of females than the males. As the male requires more amount of protein during encumberance, the thoracic muscle of encumbered male contained more protein than the gonads.
