Investigating the toxicity risk of fourteen insecticides to a biocontrol agent Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) compared to its prey Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae)

The green lacewing, Chrysoperla carnea (Stephens), is a generalist predator that suppresses major cotton pests, particularly Phenacoccus solenopsis Tinsley. However, the extensive use of insecticides negatively impacts C. carnea. To evaluate the compatibility of chemical pesticides with C. carnea, we examined the acute toxicity of fourteen insecticides and assessed their safety for C. carnea compared to its prey, P. solenopsis, under laboratory conditions. The results showed that different insecticides fluctuated extensively in their toxicities, and LC_50s ranged from 0.22 mg/L to 1842.91 mg/L. Among all the tested insecticides, the insecticide mixture (profenofos + cypermethrin) exhibited the highest toxicity to C. carnea, being 8376.86 times more toxic than the phenylpyrazole insecticide, fipronil. The results of selectivity ratios revealed that organophosphates, carbamates, and pyrethroids were non-selective with more or similar toxicity to predator and prey were classified as extremely high risk. However, all other tested insecticides were more toxic to prey and selective to predators and were categorized as medium or low risk. These findings can inform strategies that incorporate C. carnea as part of an integrated pest management program for P. solenopsis.