Effect of different diets on some biological parameters of Chrysoperla carnea (Neuroptera: Chrysopidae)

Chrysoperla carnea is a voracious predator. It is currently mass-reared and released for biological control programs. This study was aimed at finding out the effect of different diets on biological characteristics of adult predator, and to introduce a better and cheaper artificial diet for its mass-rearing. In order to obtain a pure and physiologically homogenous population, the predator reared for seven successive generations in laboratory conditions. The effect of six different diets [a mixture of 30% concentrations of glucose, fructose and sucrose (1: 1: 1), glucose, fructose, sucrose plus extract of Sitotroga cerealella eggs (1: 1), glucose, fructose, sucrose plus extract of Anagasta kuehniella eggs (1: 1), a mixture of honey, yeast and distilled water (1: 1: 1), honey, yeast plus extract of S. cerealella eggs (1: 1: 1) and honey, yeast plus extract of A. kuehniella eggs (1: 1: 1)] was studied on biological parameters (Pre-oviposition, oviposition and post-oviposition period,longevity of males and females, fecundity, egg hatchability and eggs remained in the ovary of females after death) of seventh generation. Experiments were conducted under laboratory conditions (25 ± 2ºC, 60 ± 10% RH and 16L: 8Dh) with four replications and five observations. Results revealed that the mixture of honey, yeast and extract of A. kuehniella eggs (1: 1: 1), influenced the biological traits of the predator more effectively than all other diets. The considering average longevity, oviposition period and fecundity of female (37.73 ± 0.59, 28.57 ± 1.09 days, 795.0 ± 23.05 eggs, respectively), and egg hatchability (84.98 ± 0.71 %) compared to those of other diet treatments. Minimum pre-oviposition period (6.66 ± 0.49 days) was also found in adults fed by this diet.