Biology of Tetranychus Urticae Koch (acarina: Tetranychidae) on Carnation under Laboratory Conditions

Biology of Tetranychus urticae Koch was studied under laboratory at 27.79 ± 4.40°C temperature and 79 ± 5.75 per cent RH during Sept. 2008. The finding showed that life cycle of T. urticae consisted of five stages viz., eggs, larva, protonymph, deutonymph and adult and one short inactive stage called quiescent stage. The eggs incubation period of T. urticae was 3.29±0.62 days. The larval body measured 0.14±0.01 mm in length and 0.10±0.01 mm in width and lived for 1.79±0.64 days in male and 2.71±0.57 days in female. The mature larva entered in a quiescent stage (nymphochrysalis). The total developmental period was longer in female (10.61±1.21 days) as compared to male (8.44±1.75 days). Mated female lived for longer time and laid higher number of eggs than unmated female. Mated female produced progeny consisting of both sexes, whereas, unmated female invariably gave rise to male progeny.