Location: Fruit and Tree Nut ResearchTitle: Laboratory assays against adult and larval sap beetles (Coleoptera: Nitidulidae) using entomopathogenic nematodes, microbial-based insecticides and synthetic insecticides
Submitted to: Journal of Entomological Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/17/2018
Publication Date: 1/1/2019
Citation: Cottrell, T.E., Shapiro Ilan, D.I., Horton, D.L. 2019. Laboratory assays against adult and larval sap beetles (Coleoptera: Nitidulidae) using entomopathogenic nematodes, microbial-based insecticides and synthetic insecticides. Journal of Entomological Science. 54:30-42.
Interpretive Summary: This research documents the efficacy of several species of entomopathogenic nematodes on larval Carpophilus spp. sap beetles along with the efficacy of two microbial-based insecticides and several synthetic insecticides on adults of this pest. This information will be very useful for control of this pest in peach orchards but also on other crops. Our results suggest that soil application of entomopathogenic nematodes could be used to reduce future adult populations in peach orchards. Additionally, our work identifies that some insecticides are efficacious if ingested but not when contacted as a dried residue. This is important considering that adults will contact the insecticides when on limbs, leaves and fruit but not when feeding internally on fruit thus requiring use of those limited insecticides with higher efficacy as contact insecticides.
Technical Abstract: Sap beetles, Carpophilus spp. (Coleoptera: Nitidulidae), damage peach fruit leading to the need for efficacious control measures. We assayed different species/strains of entomopathogenic nematodes (Heterorhabditis bacteriophora Vs strain, H. indica HOM1 strain, H. megidis UK211 strain, Steinernema carpocapsae All strain, S. feltiae Sn strain and S. riobrave 355 strain) against larval Carpophilus spp. and insecticides (microbial-based Grandevo® and Venerate™ Bioinsecticide along with the synthetic thiamethoxam, acetamiprid, indoxacarb, ß-cyfluthrin, clothianidan, carbaryl, chlorantraniliprole, fenpropathrin, spinetoram, phosmet, malathion and imidacloprid) against adult Carpophilus spp. in the laboratory. All entomopathogenic nematodes assayed caused significantly higher larval mortality than the control. How the insecticides were presented to the adult beetles affected whether beetles were rated non-feeding (dead + moribund). Fewer insecticides were active against the adults when applied to filter paper than when applied to a plug of pear that beetles fed upon. Overall, indoxacarb and phosmet provided consistently better control, regardless of exposure method. These two insecticides, with different modes of action, also have a 14-day pre-harvest interval when used on peach making it imperative to detect these pests well before harvest. Chlorantraniliprole and the microbial-based products had no effect on adult beetles regardless of exposure method.