Effect of Goniozus legneri gordh (Hymenoptera: Bethylidae) on the life table of Palpita unionalis Hb. (Lepidoptera: Pyralidae) [electronic resource].

Includes references.

The effects of Goniozus legneri Gordh (Hymenoptera: Bcthylidac) on the life table of Palpila unionalis Hb. (Lepidoptera: Pyralidae) at different host densities of 100. 150, 300 and 400 eggs/ 2 olive seedlings were studied in the laboratory at ahiotic factors of 25 ± 2°C; 60 ± 10% RH and photoperiod of 14 : 10 (L : D) h. Control treatments were conducted at 100 eggs! 2 olive seedlings but without releasing the parasitoid under the same conditions. Data indicated that mortality rates in eggs, first, second, third instar larvae and pupae cohorts were comparable between control and all parasitoid-released experiments. In comparison to control treatment. mortality percentage in the 4 respective parasitoid-released experiments were as high as 5.63, 5.01. 3.12 and 2.79 times in fourth instar cohorts; 5.22. 3.94. 2.85 and 2.79 times in fifth instar cohorts; 5.81. 5.37, 2.95 and 2.98 times in sixth instar cohorts. Population trend indices were positive (> 1) in all conducted experiments: being about 31.09.1.90,2.54,10.26 and 11.58 in control, 100, 150. 300 and 400 eggs! 2 olive seedlings. respectively. Also. generation survival rales in control treatment were as high as 17.38, 12.56. 2.94 and 2.79 times than in the 4 respective parasitoid-rcleased treatments. Moreover. the overall total number of C. legneri deposited eggs as well as total number of parasitized P. IIl1ionalis larvae during its lifetime did not differ signiricantly among parasitoid-rcleased treatments. However. significant differences were found in forms of overall total number of paralyzed larvae and overall total number of formed parasitoid cocoons. The possible differences in the responses of the parasitoid to P. Ill1ionalis different densities were discussed.

1