Functional Response of Chrysoperla Carnea (Stephens) (Neuroptera: Chrysopidae) Larvae to Phthorimaea Operculella Zeller (Lepidoptera: Gelechiidae) Eggs

A functional response study of the predator green lacewings, Chrysoperla carnea (Stephens) (Neuroptera, Chrysopidae) larvae to various densities of potato tuber moth, Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae) eggs was conducted under laboratory conditions of 27±1°C, 65 ± 5% RH and 14:10 h (L: D). Based on Hollingʹs disk equation, the first and third larval instars showed searching rates (a) of 1.03 and 0.894, respectively. These were greater than the second larval instar (i.e. 0.695). Handling time (Th) per prey decreased as predator aged being 0.0009 day for the third larval instar. This value was shorter than at each of the first and second larval instars (i.e. 0.0163 and 0.00148 day, respectively). The greatest theoretical maximum number of potato tuber moth eggs to be consumed was estimated for the third larval instar as 1111.11 eggs/day followed by second and first larval instars as 675.68 and 61.35 eggs/day, respectively