KK Nayar obtained his PhD (1947) from University of Travancore specializing in zoology. He served as the Guest Research Worker, Rothamstead Experimental Station, UK (1953-54); Commonwealth Visiting Professor, School of Biological Sciences, University of East Anglia, UK (1968-69); Professor and Head, Department of Zoology, University of Kerala, Trivandrum.
Academic and Research Achievements:Starting his research career as a taxonomist, Nayar made a survey of the gall insects of Travancore and made some important contributions to our knowledge about this group of insects. Professor Nayar’s major field of interest has however, been insect endocrinology. His first publication in this field appeared in 1953. This was the time when structure of the neuroendocrine system was exhaustively being surveyed bases on light microscopy. Functional elucidation, and work at ultrastructural level had just started. Thus Professor Nayar was in the front line in this field when he elucidated the structure of the neuroendocrine system of Iphita, Locusta, in the larvae of gall midges, and in the wheat blossom midge Sitodiplosis, covering the neurosecretory cells, their tracts, the copus cardiacum, the corpus allatum and the prothoracic glands. While studying the neurosecretory system of the fruitfly Chaetodacus cucurbitae, he found that in addition to the brain, the thoracic and abdominal ganglia also contained well defined neurosecretory cells at characteristic positions; of particular interest was his finding that the nerve emerging from the abdominal ganglion innervating the gut contained neurosecretory granules. This finding of the ‘neurosecretory innervation’ of the motor organs has later been confirmed in other insects and gave rise to a new concept in neurosecretory control of motor organs. Nayar laid emphasis on experimental work.
Other Contributions:Nayar established an association for advancement of entomology and initiated steps to found Entomon.
Awards and Honours:Nayar was a Fellow, Indian Academy of Sciences, Bangalore. He was UGC National Lecturer (1971).