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Table 2 Population densities and reduction (%) of the whitefly, B. tabaci, on squash plants received two releasing rates of the second larval instar of C. carnea

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

  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)
6.13
± 4.1A
14.60
± 6.6A
21.13
± 7.6A
26.33
± 8.5A
24.73
± 7.8A
15.93
± 6.6A
10.67
± 4.5A
5 5.60
± 3.4A
10.87
± 3.5B
25.62
± 12.9
14.00
± 6.0B
33.68
± 5.4
15.27
± 6.5B
41.22
± 16.0
12.60
± 7.0B
49.00
± 27.2
7.73
± 5.5B
51.54
± 11.8
3.87
± 3.3B
63.76
± 19.2
10 6.33
± 3.1A
6.20
± 4.5C
57.54
± 17.9
4.13
± 3.0C
80.50
± 10.3
1.40
± 1.5C
90.98
± 4.7
0.87
± 1.1C
93.32
± 4.3
0.27
± 0.8C
96.62
± 5.6
0.00 C 100
F values
(with df = 2.42)
0.173 10.451 31.849 60.179 58.327 37.313 43.018
T values
(with df = 1.8)
3.237 9.001 6.658 3.600 7.72 4.215
P 0.842 < 0.001 0.012 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 0.007 < 0.001 < 0.001 < 0.001 0.003
  1. Means within each column bearing different superscript letters are significantly different according to Duncan test (P = 0.05). Infestation = no. of whitefly nymphs per leaf (mean ± SD). Reduction = percentage (%) of reduction comparing to control (mean ± SD)