Induced sterility by gamma radiation in Callosobruchus maculatus (Col.: Bruchidae) and sterile insect release ratio to a normal population

Effects of gamma radiation doses on Callosobruchus maculatus (F.) were studied. In this study different doses including 0, 20, 35, 50, 60 and 70 Gy were used in the pupal stage and emerged adults were separated before mating and crossed in treatments including: normal male ï´ normal female, normal male ï´ irradiated female, irradiated male ï´ normal female and irradiated male ï´ irradiated female. Comparing means (Duncan,s test, 0.05) showed that in 20 Gy, all treatments had significant difference, except normal male ï´ normal female and normal male ï´ irradiated female. In 35 Gy, all treatments had significant difference. The most sterility was observed in irradiated male ï´ irradiated female and it was not significantly different with irradiated male ï´ normal female. In 50 Gy, treatments which contained irradiated males or irradiated females had significant difference with treatments containing normal males and females. In 60 and 70 Gy, hatchability percentage in the next generation, both for sterile males and sterile females, reduced population significantly. Therefore, 60 to 70 Gy induce sterility in this insect. Sterile insect release to a normal population was studied in three cases including: sterile male, sterile female and sterile male and female releases. Results indicated that sterile female release had no effect on reducing population in the next generation. Sterile male release and sterile male and female release had identical effects. As a regard to the fact that separating males and females is difficult and time consuming, therefore, it seems that sterile male and female release in the ratio of 10:10:1:1 (irradiated male ï´ irradiated female ï´ normal male ï´ normal female) cause the best result in population reduction in the next generation

Using sterile insect technique against Carob moth, Ectomyelois ceratoniae (Zeller) (Lep.: Pyralidae), in Yazd province, Iran

Carob moth, Ectomyelois ceratoniae (Zeller) (Lep.: Pyralidae), is the most important pest of pomegranate fruit in Iran where the cryptic activity of its larva makes the application of insecticides practically impossible. In this research, we evaluated the viability of the sterile insect technique against the carob moth in two isolated regions in Yazd province (Aqda and Mehriz). The mass rearing of the pest was performed in clean rooms on artificial diet under environmental conditions, 29±1 ºC and 75±5 %RH applying 165 Gy gamma ray as sterilizing doze. The sterile insects were released periodically in Aqda orchards (45 hectares) and in Chah Sheida (12 hectares) in Mehriz between March and November 2015. The infestation rate of carob moth in Aqda and Mehriz significantly reduced, in both target regions and control areas, by 12.27% and 44.02%, as well as 12.06% and 50.11%, for Aqda and Mehriz, respectively. It was concluded that periodical release of sterile carob moths can effectively lower the density of pest population and its economic loss on the harvest