Abstract

                                In recent years, considerable interest has been evoked all over the world in the application of biological methods of controlling crop pests. Three of the major reasons for this have been: (1) the rapid development of resistance in insect and mite pests to many chemical pesticides, (2) the hazards that many of the recently developod organo- phosphorous and other toxic compounds pose to human and wild life and (3) the development of serious outbreaks subsequent to the use of a chemical pesticide, resulting from annihilation of existing natural enemy populations. Whatever other reasons there may be, it is gratifying to note that greater interest is now being taken in biological control and measures being taken to prevent further serious upsets in the balance of nature.

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