Predicting population parameters of Chrysoperla carnea Stephens preying on pesticide-treated nymphs of Agonoscena pistaciae Burckhardt and Lauterer

ABSTRACT The population parameters of Chrysoperla carnea were evaluated after its 3rd instar larvae were fed for 48 hrs by 5th instar nymphs of Agonoscena pistaciae treated with the field-recommended doses of the spirotetramat and imidacloprid pesticides. In the control, distilled water-treated prey was used. The age-stage, two-sex life table approach was employed to analyse the data. Results showed that the male and female eggs of the predator took 4 days to hatch on average in all treatments. In general, the male and female larvae and pupae of C. carnea in the control treatment developed significantly faster than those in the spirotetramat and imidacloprid treatments. Total preadult durations of the male and female predators were significantly shorter in the control (20.19 and 20.74 days) compared with those in the spirotetramat (22.87 and 22.22 days) and imidacloprid (21.84 and 22.36 days) treatments. Female C. carnea had the longest adult longevity in the control (82.11 days), followed by that of imidacloprid (69.10 days) and spirotetramat (60.00 days) treatments, respectively. The longest adult preoviposition period was 21.90 days in the imidacloprid and the shortest one in the control (13.92 days). The net reproductive rate (R0) and the intrinsic rate of increase (r) of C. carnea were 364.42, 169.01, and 123.16 offspring, and 0.1320, 0.0891, and 0,1064 d-1, in the control, spirotetramat, and imidacloprid treatments, respectively. The studied pesticides could substantially decline the population parameters of C. carnea.