<prompt> Dose of DDT for effective control of mosquitoes is -1-2 gm25-6 gm22-4 gm22-4 gm2  <response>: DDT: DDT is an indoor residual spray DDT is the insecticide of choice and dosage of 1-2 grams of pure DDT per sq.metre are applied 1-3 times a year to walls and other surfaces where mosquitoes rest. Duration of effectiveness is 6 to 12 months Parks Textbook of Preventive and Social Medicine, 25th Edition, Pg 833 