Abstract

                                The study of economic entomology has in these days attained such dimensions that various methods of control are being advocated for checking insects injurious to crops. The mechanical methods of control such as the use of insecticides, spraying, fumigation and other artificial devices such as the use of light traps, etc., have been in some cases found impracticable and uneconomical. In view of the poisonous nature of the insecticides themselves, the prohibitive cost of the treat- ments in some cases, the frequency and thoroughness with which these treatments have to be given, the promptness with which these have to be done, and the several meteorological factors that influence the success or failure of the results obtained and lastly the temporary and palliative nature of the results obtained, mechanical methods of control frequently become very much limited in their scope.

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