Comparing effects of insecticides on two green lacewings species, Chrysoperla johnsoni and Chrysoperla carnea (Neuroptera: Chrysopidae).

This study compared lethal and sublethal effects of five insecticides, chlorantraniliprole, cyantraniliprole, spinetoram, novaluron, and lambda-cyhalothrin, on adult and second instars of two green lacewing species, Chrysoperla carnea (Stephens) and Chrysoperla johnsoni Henry, Wells and Pupedis (Neuroptera: Chrysopidae) in the laboratory. Formulated pesticides were tested using concentrations equivalent to the high label rate dissolved in 378.5 liters of water. Novaluron and lambda-cyhalothrin were toxic to larvae and no treated larvae survived to the adult stage. Larva to adult survival was reduced in chlorantraniliprole, cyantraniliprole, and spinetoram treatments. Larva to adult developmental time and sex ratio were not different among the treatments within a species. Chlorantraniliprole, cyantraniliprole, spinetoram, and lambda-cyhalothrin treatments were highly toxic to adults of both species. C. johnsoni females had lower fecundity than C. carnea females in the control. Fecundity of females was similar in the control and novaluron treatment within each species. However, fertility and egg viability were negatively impacted for both species when females were treated with novaluron. C. carnea females had higher fertility and egg viability than C. johnsoni females in the control. Adults of both species had similar longevity in the control and novaluron treatment and adult longevity was not gender specific. All insecticides tested were toxic to C. johnsoni and C. carnea either at the immature or adult stage or both. Results of this study demonstrate a similarity between C. johnsoni and C. carnea for pesticide toxicity irrespective of their varied geographical distributions.