Efficacy of conventional and biorational insecticides against the invasive pest thrips parvispinus (thysanoptera: thripidae) under containment conditions

Authors: ATAIDE, LIVIA - University Of Florida; VARGAS, GERMAN - Cornell University; VELAZQUEZ-HERNANDEZ, YISELL - University Of Florida; ARAUZ, ISAMAR - University Of Florida; VILLAMARIN, PAOLA - University Of Florida; CANON, MARIA - University Of Florida; Yang, Xiangbing; RILEY, SIMON - University Of Florida; REVYNTHI, ALEXANDRA - University Of Florida

Submitted to: Insects
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/9/2024
Publication Date: 1/10/2024
Citation: Ataide, L.M., Vargas, G., Velazquez-Hernandez, Y., Arauz, I.R., Villamarin, P., Canon, M.A., Yang, X., Riley, S.S., Revynthi, A.M. 2024. Efficacy of conventional and biorational insecticides against the invasive pest thrips parvispinus (thysanoptera: thripidae) under containment conditions. Insects. 15(1):48. https://doi.org/10.3390/insects15010048.
DOI: https://doi.org/10.3390/insects15010048

Interpretive Summary: Immediately after detection, the Florida Department of Agriculture and Consumer Services, Division of Plant Industry has implemented quarantine action and regulatory conditions has been placed against this thrips. In order to screen efficient insecticides for controlling this pest, ARS scientist in Miami, Florida, collaborating with scientists from University of Florida, and Cornell University, evaluated the contact and residue toxicity of 32 insecticide products against larval and adult T. parvispinus, to screen the safe and effective insecticides for management of this pest under the laboratory conditions in a containment facility. Results showed that chlorfenapyr, sufloxaflor-spinetoram, and spinosad were most effective and casued the highest mortality across all stages in both contact and residue trials. Pyridalyl, acetamiprid, tolfenpyrad, pyridalyl, cyantraniliprole-flonicamid, acephate, novaturon, abamectin, cyantraniliprole, imidacloprid, cyclaniliprole, spirotetramat and carbaryl displayed moderate toxicity on at least two stages. Additionally, chlorfenapyr, spinosad, sufloxaflor-spinetoram, pyridalyl, acetamiprid, cyclaniliprole, cyclaniliprole-flonicamid, abamectin, and acephate inhibited larvae and adult’s feeding in both contact and residue tests. Horticultural oils such as mineral oil (3%), and sesame oil caused the highest mortality and feeding inhibition. Greenhouse evaluations and rotation program incorporating the effective products needs to be done in future and optimal use of insecticides with different modes of action is advised for better management of this pest to avoid resistance development on ornamental crops.

Technical Abstract: In 2020, the invasive Thrips parvispinus (Karny) was first detected in Florida, United States. In response to the implemented regulatory restrictions, we conducted laboratory experiments under containment conditions. Thrips larvae and adults were exposed to 32 products (conventional and biorational insecticides) either directly or indirectly. Direct exposure was performed using a Spray Potter Tower, while indirect exposure was conducted by evaluating residue toxicity against the thrips. Water served as a control. We assessed mortality and leaf-feeding damage 48 h post-treatment. Among the conventional insecticides, chlorfenapyr, sulfoxaflor-spinetoram, and spinosad caused high mortality across all stages in both direct and residue toxicity assays. Pyridalyl, acetamiprid, tolfenpyrad, cyclaniliprole-flonicamid, acephate, novaluron, abamectin, cyantraniliprole, imidacloprid, cyclaniliprole, spirotetramat, and carbaryl displayed moderate toxicity, affecting at least two stages in either exposure route. Additionally, chlorfenapyr, spinosad, sulfoxaflor-spinetoram, pyridalyl, acetamiprid, cyclaniliprole, cyclaniliprole-flonicamid, abamectin, and acephate inhibited larvae and adult’s leaf feeding damage in both direct and residue toxicity assays. Regarding biorational insecticides, mineral oil (3%) and sesame oil caused the highest mortality and lowest leaf-feeding damage. Greenhouse evaluations of spinosad, chlorfenapyr, sulfoxaflor-spinetoram, and pyridalyl are recommended. Also, a rotation program incorporating these products, while considering different modes of action, is advised for ornamental growers to avoid resistance and to comply with regulations.