Biological Control - Recapitulating The Basic Principles

The basic principles of biological control of pests and diseases obviously remain the same, whether applied to insect pests, nematodes or plant pathogenic fungi and bacteria. There is an increasing trend towards expanding the ambit of biological control to encompass the phenomena of antibiosis, host resistance, auto-sterilization, genetic manipulation of species, cropping sequences etc. as well. In the recent years, considerable research efforts have been directed towards studying antibiosis and its application in biological suppression of pathogens – and therefore, this topic deserves a separate treatise. However, in this article I intend to discuss the narrower concept of biological control, i.e., classical bio-control which is delimited by the phenomena of predation, parasitism and pathogenesis. Some of the views expressed herein have been raised previously by illustrious workers (Kerry, 1990a, b) and these still remain relevant for directing meaningful research.