Behavioral Responses of Pest Mole Crickets, Neoscapteriscus SPP. (Orthoptera: Gryllotalpidae), to Selected Insecticides

BACKGROUND Mole crickets (Neoscapteriscus spp.) consume turfgrasses and pasture grasses and uproot plants by their tunneling, which decreases turf aesthetics and decreases forage quantity and quality. Insecticides are frequently used to prevent damage. In typical field trials, damage symptoms, not percent of mortality or achieved level of control, are used to assess treatment efficacy. Here however, we evaluated the direct effect of key insecticides on Neoscapteriscus mole cricket behavior. RESULTS Mole crickets, Neoscapteriscus spp. were able to detect and avoid areas treated with fipronil (FP) and imidacloprid (FP). They tunneled less in sand treated with fipronil; and avoided sand treated with fipronil and imidacloprid if given a choice. Mole crickets escaped areas treated with acephate, bifenthrin and fipronil. Bifenthrin and acephate caused increased tunneling during the first 90 min of observation. Fipronil and imidacloprid significantly reduced overall tunneling on treated areas. CONCLUSIONS Tested insecticides elicited two types of behavioral changes in Neoscapteriscus mole crickets: increased locomotory activity and tunneling (acephate [organophosphate] and bifenthrin [pyrethroid]) and reduced spatial movement (fipronil [phenylpyrazole] and imidacloprid [neonicotinoid]). These behavioral responses resulted mainly from contact chemoreception and inherent neurotoxicity of the chemicals on Neoscapteriscus mole crickets.