Field evaluation of indigenous predacious insect, Chrysoperla carnea (Steph.) (Neuroptera: Chrysopidae), fitness in controlling aphids and whiteflies in two vegetable crops

Egyptian Journal of Biological Pest Control

Table 1 Population densities and reduction (%) of the aphid, A. gossypii, on squash plants received two releasing rates of the second larval instar of C. carnea

	28 Jul.	7 Aug.		17 Aug.		27 Aug.		6 Sep.		16 Sep.		26 Sep.
Releasing rate per plant	Infestation	Infestation	Reduction	Infestation	Reduction	Infestation	Reduction	Infestation	Reduction	Infestation	Reduction	Infestation	Reduction
Control (untreated plants)	52.13 ± 13.7^A	103.00 ± 21.9^A	–	179.80 ± 52.2^A	–	192.93 ± 37.3^A	–	126.47 ± 36.0^A	–	68.93 ± 23.3^A	–	24.47 ± 8.4^A	–
5	47.87 ± 11.3^A	88.27 ± 17.0^B	14.32 ± 7.4	118.47 ± 29.1^B	34.08 ± 5.0	106.20 ± 20.1^B	44.96 ± 6.7	66.20 ± 12.9^B	47.68 ± 7.6	19.33 ± 7.9^B	67.84 ± 14.2	6.40 ± 2.9^B	73.88 ± 4.5
10	49.47 ± 13.0^A	75.60 ± 14.3^B	26.56 ± 10.6	49.13 ± 16.2^C	72.68 ± 6.5	17.87 ± 7.3^C	92.00 ± 0.7	8.73 ± 5.1^C	93.10 ± 2.8	3.60 ± 3.0^C	94.74 ± 2.0	1.93 ± 1.8^C	92.08 ± 2.1
F values (with df = 2.42)	0.432	8.730	–	50.237	–	186.907	–	105.003	–	85.274	–	77.561	–
T values (with df = 1.8)	–	–	2.125	–	10.542	–	15.572	–	12.482	–	4.198	–	8.147
P	0.652	< 0.001	0.066	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001

Means within each column bearing different superscript letters are significantly different according to Duncan test (P = 0.05). Infestation = no. of aphid nymphs per leaf (mean ± SD). Reduction = percentage (%) of reduction comparing to control (mean ± SD)