V K K Prabhu
Articles written in Proceedings – Animal Sciences
Volume 94 Issue 3 June 1985 pp 197-205
Hormones play an important role in insect behaviour. These hormones are mainly the neurohormones of the brain and of the corpus cardiacum, the juvenile hormone of the corpus allatum and the ecdysone of the prothoracic glands. These produce either releaser effects or modifier effects. Hormonal modulation of neurophysiological activity controlling various aspects of behaviour, hormonal influence of reproductive behaviour in the male and the female insects, their role in migration, as well as hormonal influence of caste determination and behaviour of social insects, have been discussed.
Volume 94 Issue 5 October 1985 pp 489-501
Embryonic development of
Volume 95 Issue 4 July 1986 pp 379-385
Final (3rd) instar larvae of the coconut rhinoceros beetle
Volume 96 Issue 3 May 1987 pp 181-184
The essential polyunsaturated fatty acids required by insects in their food appear to be needed for prostaglandinogenesis. Prostaglandins themselves are likely to be widely distributed in insects playing perhaps an hitherto unsuspected important role as in reproduction.
Volume 97 Issue 1 January 1988 pp 55-65
The effect of topical application of juvenile hormone analogues farnesyl methyl ether and kinoprene (ZR 777) at different doses to eggs immediately after laying, germ band formation and blastokinesis, produced different types of abnormal embryos with varying degrees of derangement of development, most of them ultimately resulting in failure to hatch. Some of the embryos were almost normal but failed to hatch even though they continued to develop inside the chorion and died two days later. On the whole, there was correlation between dose of the analogue applied and mortality rate. Kinoprene was much more effective than farnesyl methyl ether. With given dose, per cent embryonic mortality was more or less the same whether the analogues were applied just after oviposition or germ band formation, but was lesser when applied immediately after blastokinesis. The period just after germ band formation appeared to be most sensitive. Treatments affected the endocrine system. The neurosecretory index was higher in the treated embryos. Prothoracic glands and their nuclei showed considerable enlargement in treated embryos continuing development inside chorion even after their controls hatched. The corpus allatum was smaller in treated embryos and corpora cardiaca were filled with neurosecretory material. Cuticle development was abnormal after treatment.
Volume 97 Issue 1 January 1988 pp 67-71
Protease, amylase, lipase and trehalase are present in the larval and adult midguts of
Volume 97 Issue 1 January 1988 pp 73-78
The effect of midgut epithelial extract on digestive enzyme secretion in the third instar larva of
Volume 99 Issue 6 November 1990 pp 447-455
The coconut rhinoceros beetle
Stridulatory mechanism comprises rubbing of a specialised region along the margin of the apex of the elytron —the pars stridens, against a series of striations —the plectrum, occupying the dorsum of the 7th abdominal tergite. Stridulation is possible with a single pars stridens, either of the left or right elytron, both being identical. No sexually dimorphic difference is apparent in the pars stridens. Plectral structure exhibits sexual dimorphism, being much prominent in the male.
Wing-locking is necessary to keep the elytra in the stridulatory position. Locking is effected by a longitudinal flange along the median side of one elytron (either the left or right, irrespective of the sex) fitting into a corresponding depression along the other. This differs from the reported cases in other coleopterans in which the flange of the left elytron extends under the right when locked.