High temperature treatment on the eggs of the mosquito, Culex quinquefasciatus Say and its effects on the subsequent stages developed therefrom
The eggs of Culex quinquefasciatus Say (Diptera: Culicidae) were exposed to 40oC for different exposure periods (viz. half an hour, one, two and four hours) and control (room temperature, 28±6oC); the percentage of egg hatching ranged from 74.14 to 96.33 (F=215.593, P<0.05), larval mortalities were from 24.52 to 0.00% (F=73.287, P<0.05), pupal mortalities ranged from 10.2 to16.71% (F=34.056, P<0.05), mean larval periods ranged from 127.9 to 155.3 hours (F=124.002, P<0.05), mean pupal periods ranged from 30.5 to 36.1 hours (F=10.531, P<0.05), lengths of 2nd instar ranged from 3.82 to 4.67 mm (F=16.50, P<0.05), lengths of 3rd instar ranged from 6.195 to 7.195 mm (F=7.558, P<0.05), lengths of 4th instar ranged from 7.395 to 8.025 mm (F=3.961, P<0.05), mean diameter of the head capsule of 1st instar larvae was 0.316 to 0.384 mm (F=8.308, P<0.05), that of 2nd instar larvae was 0.395 to 0.468 mm (F=4.953, P<0.05), that of 3rd instar larvae was 0.652 to 0.71 mm (F=2.629, P>0.05), that of 4th instar larvae was 0.806 to 0.91 mm (F= 13.871, P<0.05), length of the cephalothorax of pupae ranged from 1.862 to 2.062 mm (F=0.662, P>0.05), body length of male adults ranged from 3.41 to 3.58 mm (F=0.59, P>0.05), and that of female ranged from 3.75 to 4.09 mm (F=1.98, P>0.05), mean egg- rafts laid per female ranged from 1.4 to 2.0 and mean numbers of eggs per raft were 230 to 260.
J. Asiat. Soc. Bangladesh, Sci. 39(2): 247-257, December 2013