AN EVALUATION OF THE PARASITOID, APHIDIUS-COLEMANI VIERECK (HYMENOPTERA, BRACONIDAE) AND THE PREDATOR APHIDOLETES-APHIDIMYZA RONDANI (DIPTERA, CECIDOMYIIDAE) FOR BIOLOGICAL-CONTROL OF APHIS-GOSSYPII GLOVER (HOMOPTERA, APHIDIDAE) ON CUCUMBER

Developmental time and fecundity of Aphidius colemani Viereck and Aphi doletes aphidimyza Rondani were studied under laboratory conditions on cucumber plants infested with Aphis gossypii Glover at a constant tem perature of 20 degrees C, photoperiod of 18 hours and 70% R. H. Develo pmental time from egg to adult for A. colemani lasted 13.9 days and fo r A. aphidimyza, from egg to larva was 3 days, larva to pupa 5.8 days, from pupa to adult 11.9 days, and total developmental time was 20.6 d ays. The average Lifetime fecundity was 57.7 for A. colemani and 55.07 for A. aphidimyza. The variation for both species was considerable. P ercentage of females for A. colemani was 58% and for A. aphidimyza 66% . One larva of A. aphidimyza will, on average, kill 23.8 A. gossypii d uring its life. Predation of parasitized aphids by A aphidimyza was ob served. Production of parasitoids was lower when the predator was pres ent. The use of the two natural enemies together in control programs a gainst A. gossypii is discussed.