BAGHDADI¹, F. SHARIFI² and MIRMOAYEDI²

Comm. Appl. Biol. Sci, Ghent University, 774, 2012 635 INVESTIGATION ON SOME BIOLOGICAL ASPECTS OF CHRYSOPERLA LUCASINA CHRYSOPIDAE: NEUROPTERA ON BEMISIA TABACI IN LABORATORY CONDITIONS A. BAGHDADI¹, F. SHARIFI² and A. MIRMOAYEDI² 1 Department of Agricultural Science, Payame Noor University PO BOX 19395-3697, Tehran- IRAN 2 Department of Plant protection, Agricultural Faculty, Razi University, Kermanshah-IRAN Corresponding author E-mail: mbaghdadiusyahoo.com SUMMARY Bemisia tabaci is one of the most important key pests of many types of cultivated plants. Lacewings Chrysopidae: Neuroptera are predatory insects, widely used in biological control programs. Between them green lacewing is a promising biological control agent of pests in green houses and crop fields. In this study, gravid females of the green lacewing Chrysoperla lucasina Lacroix were captured from Sarepolzahab altitude 540m, latitude 34°,14´ N 46°,9´ E in western part of Iran. Collected insects were reared in a growth chamber, under experimental conditions 25±1°C, 70±5 RH and a photoperiod of 16:8 L: D. Different diets were offered to larvae which consisted of a whitefly species B.tabaci, an aphid Myzus persica and also lyophilized powder of drone honeybee Apis melifera. As different foods were used to nurish larvae, so for each diet, mean larval period were calculated, and finally means were compared to each other. Anova in MSTAT-C was used for analysis of variance, and Duncan multiple range test DMRT to compare between means. The results showed that larvae had maximum duration of 27±0.33 days when fed on honeybee lyophi- lized powder and the minimum value was 17.9±0.3 days for B. tabaci. 25±0.27 day recorded for M. persicae. Food preference of the 3 rd instar larvae of green lacewing was surveyed, they showed a food preference to M. persicae, to compare with B. tabaci, as the former has a bigger body size, so more easily to be captured by the predator larvae. The 3 rd instar larvae of lacewing were more voracious on preys, than the 1 st or the 2 nd instar larvae. Statistically speaking, there were a significantly difference when mean of different preys consumed by predator larvae were compared. We found, that when the predator larvae have fed on B.tabaci, their development time was shorter, and when arrived to adult stage, the adults showed, an improved fertili- ty. The results indicated that the suitable prey not only can increase the rate of through accelerating devel- opmental stages of the predator and by means of an increase in its pupal body weight consequently promoting the fecundity of resulting adults, but also can alter predators population density in relation to own production numbers. Key words : Chrysoperla lucasina, Bemisia tabaci, Biological control INTRODUCTION Bemisia tabaci is a plant sap sucking insect belonging to the family Aleyrodidae. It is broadly polyphagous, feeding on an estimated 500 plants species Greathead, 1986 from 60 plant families Mound and Halsey, 1978, Jiang et al., 1999, Hilje et al., 2001. Since the early 1980’s it has caused escalating problems to field and protected agricultural crops and ornamental plants in the world. Heavy infestations of B.tabaci may reduce host vigor and growth, cause chlorosis and uneven ripening and induce physiological disorders. The larvae produce hon- 636 eydew on which sooty moulds grow, reducing the photosynthetic capabilities of the plant, resulting in defoliation and stunting. B.tabaci is also a vector of 111 plant viruses, some of which are of high economic importance. Resistance to approximately 35 active ingredients has been reported for B.tabaci in at least 20 countries worldwide Roditakis, 2005. Chrysopids are polyphagous predators that can suppress population of many pest species Hydron, 1971 such as whiteflies, thrips and leafhoppers Plincipi and Canard, 1984. Their efficacy in biological control of whiteflies and aphids as well as other arthropod pests has been recognized for more than 250 years Pappas, et al. 2011. These polyphagous predators can be easily reared on artificial diets and used for controlling agricultural insect pest Cohen and Smith, 1998. For every biological control, to be successful, primarily, it’s of outmost importance, to evalu- ate the potential of the predator for targeted preys Al-Zyoud and Sengonca, 2004. In this study different diets offered to larvae and longevity of life for each larval instars and food preference were evaluated. Analysis of variation was done by using ANOVA and com- paring between means by Duncans multiple range test DMRT, utilizing MSTAT-C software. MATERIALS AND METHODS Adult insects of C. lucasina were collected by netting from fields of sare-polezahab altitude 540 m , 34°, 14´N46°.9´E in western part of Iran. Rearing was carried out in UPVC pipes height 20, diameter 15 cm after species discrimination. 10 honey was used as diet for ovipositing adults, the eggs were collected on paper sheets. Deposited eggs were collected daily and transported to cold chamber 5-6°C. Experiments started with transport of egg to growth chamber 25±1°C, 16L: 8D and 70±5 RH. First instar larvae hatched after an incubation period and reared on artificial diet after 1-12 hours. In rearing, different diets offered to larvae consisted of a whitefly species B. tabaci, an aphid M. persica and also lyophilized powder of drone honeybee Apis melifera. Consumption rate of different diets used in this study were carried out in 5 replications in each 2 treatment based on completely randomized design. Nymphs of B. tabaci and M. persicae were used as live. Larval development and nymph consumption rate was counted each 12 hours with considering different foods used. Longevity for each larval instar was evaluated. Analysis of variation and comparing between means carried by use ANOVA and duncan multiple range test DMRT respectively. RESULTS AND DISCUSSION The biology and behavior of C. lucasina larvae is dependent on the quality of food which they fed on. Consumption rate of different larval instars of green lacewing C. lucasina on B. tabaci and M. persicae showed maximum larval consumption. Analysis of variation showed maximum larval differences between preys at level of 1 table 1a and 1b. The results of life history experiments showed that C.lucasina was able to develop and reach the adult stage by feeding on mean 444.2 and 281.8 third instars of B.tabaci and M. persicae, respec- tively. Consumption rate of different larval instars is showed in Table 1a. The result shows signifi- cant difference between larval instars at 5 level. As it is seen from Table 1a, the highest feeding rate of the lacewing belonged to the 3 rd instar larvae Longevity of larval duration on B. tabaci, M. persicae and lyophilized powder of A. melifera was investigated. The results showed significant difference between B. tabaci and other Comm. Appl. Biol. Sci, Ghent University, 774, 2012 637 diets at level 1 table 2a and 2b. Longevity of larvae had maximum duration 27±0.33 days when fed by honeybee lyophilized powder and minimum 17.9± 0.3 days was recorded for B. tabaci. 25±0.27 days recorded from M. persicae. Alikhan and Wan 2004 reported 18.6 days for larval duration C. pallens feeding on B. tabaci.