Chrysoperla carnea (Steph.) is one of the important and effective natural enemies of Aphis gossypii Glov. Different life stages of this predator are employed for pest control. Egg release stage is more advantagous as compared with the other stages. In this study, two methods of egg release were compared: Distribution of eggs while mixed with sawdust and ground corn as egg carriers, and egg release-using chrysobag (the special netted bag). Egg release was carried out in 3 treatments. Egg mixed with sawdust; egg mixed with ground corn and control (without carrier) in 10 replicates. Percent egg mortality was calculated during the stages of separating eggs from the surface of the oviposited paper, egg screening, and from eggs that were mixed with sawdust and did not hatch. This experiment was conducted in 7 replicates. Percent egg and larval mortality in chrysobag method was calculated in 4 treatments of 25, 50, 70 and 100 eggs in a bag, with 6 replicates. The numbers of larvae exited from a bag and also those eaten by others in each bag were determined. Results indicated that the two carriers of eggs and control were significantly different at 1%. Mortality 100 eggs mixed with sawdust and gravity corn were 6.6% and 11.6% respectively. Egg mortality for eggs that did not hatch and during eggs separation from surface of the oviposited paper, eggs screening and eggs combination with sawdust were 6%, 13%, 5% and 6% respectively. In General, 70% of the eggs hatched into larvae. From the 30% mortality observed, 24% was related to the preparing stages as well as eggs mixed with sawdust. In chrysobag method, mortality was the least while the most larvae exiting from the bag that contained 50 eggs. The results indicated that percent egg mortality in chrysobag method was less than in egg distribution with sawdust as carrier and the former method is more suitable than the others for the pest’s control.
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