Parasitic Effects of Solitary Endoparasitoid, Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae) on Cotton Mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae)

Parasitization has an enormous impact on host physiology, development and reproduction. The effect of parasitism by endoparasitoid, Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae) on survival and reproduction of mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) on different host stages was studied. Our data reveals that host mealybugs parasitized by the wasp at the 2nd instar stage were died during the 3rd instar stage of their life. However, those parasitized at the 3rd instar stage could reach the adult stage and were able to produce their progeny. After 6 days of parasitization, all parasitized hosts of the 2nd, 3rd and adult stages were died except the 1st instar. Results showed that parasitized host mealybugs had significantly lower reproductive potential than the unparasitized ones. Maximum parasitoid emergence was recorded in the 3rd instar host stage. This basic research regarding survival and reproduction of the parasitized host mealybugs would be very helpful in devising sustainable biological control strategies for cotton mealybug.

Effect of body material and temperature variation on the performance of the time delay pyrotechnic compositions

Significance of body material and temperature variation on burning time and burning rate of Si/Pb O/Pb_3O_4/FG and B/BaCrO_4/FG pyrotechnic delay compositions were experimentally studied. Brass and stainless steel were used as delay body materials. High resolution oscilloscope and a customized chronometer were simultaneously used for the measurement of burning time and burning rate. Results reveal that brass material with controlled column dimensions reduced the variation in burning time of Si/Pb O/Pb_3O_4/FG delay mixture from 7.43% to 4.17% and that of B/Ba CrO_4/FG mixture from 16.83% to 9.39%.Similarly the variation in burning rate was reduced from 7.57% to 4.12% and from 17% to 9.69% for Si/Pb O/Pb_3O_4/FG and B/BaCrO_4/FG mixtures respectively. Si/PbO/Pb_3O_4/FG delay mixture was also subjected to temperature ranging from -54℃ up to+100℃. The burning rate of this composition varied linearly with temperature. Burning rate increased from 28.01 mm/s to 34.38 mm/s when the temperature was varied from -54℃ to +100℃.