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ARS Home » Southeast Area » Byron, Georgia » Fruit and Tree Nut Research » Research » Publications at this Location » Publication #409465

Research Project: Novel Approaches for Managing Key Pests of Peach and Pecan

Location: Fruit and Tree Nut Research

Title: Enhancing Entomopathogenic Nematode Efficacy with Pheromones: A Field Study Targeting the Pecan Weevil

item PERIER, JEMAINE - University Of Georgia
item KAPLAN, FATMA - Pheronym, Inc
item LEWIS, EDWIN - University Of Idaho
item ALBORN, HANS - US Department Of Agriculture (USDA)
item SCHLIEKELMAN, PAUL - University Of Georgia
item TOEWS, MICHEAL - University Of Georgia
item Shapiro Ilan, David

Submitted to: Journal of Invertebrate Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/23/2024
Publication Date: 3/14/2024
Citation: Perier, J.D., Kaplan, F., Lewis, E.E., Alborn, H., Schliekelman, P., Toews, M.D., Shapiro Ilan, D.I. 2024. Enhancing Entomopathogenic Nematode Efficacy with Pheromones: A Field Study Targeting the Pecan Weevil. Journal of Invertebrate Pathology. 56/e2024.

Interpretive Summary: Entomopathogenic nematodes are small round worms usually that can control pests naturally without using chemicial pesticides. When exposed to a family of natural nematode pheromones, the nematodes become better at moving and an infecting insect pests in labs and greenhouses. This study is the first to try using these pheromones to make entomopathogenic nematodes better at their job in the field. A nematode called Steinernema feltiae was used in this study because it is easily obtained and good at killing insect pests like the pecan weevil. The pecan weevil is a major pest of pecan. We exposed S. feltiae with and without pheromones to see if the pheromoens would improve the killing power of the nematodes. Even though we tested S. feltiae in very cold conditions, the nematodes were great at killing the pecan weevil when exposed to the pheromones, better than the nematodes were applied by themselves. This meant that using the pheromones made S. feltiae better at its job. Using pheromones is a new way to improve the use of entomopathogenic nematodes in the field, which also means using less pesticides and protecting the environment.

Technical Abstract: Entomopathogenic nematodes are used widely as biocontrol agents. Approaches to enhance the biocontrol efficacy of entomopathogenic nematodes are desirable. When exposed to ascaroside pheromones, entomopathogenic nematodes have been shown to increase dispersal, infectivity, and efficacy under laboratory and greenhouse conditions. Prior to this study, the impact of entomopathogenic nematode-pheromone combinations on field efficacy had not been studied. Steinernema feltiae is a commercially available entomopathogenic nematode that has been shown to induce mortality in pecan insect pests such as the pecan weevil, Curculio caryae. In this study, the pecan weevil was used as a model system to evaluate changes in S. feltiae efficacy when sensitized with an ascaroside pheromone mixture. Following exposure to the pheromone mixtures, the performance of S. feltiae significantly increased despite being tested in unfavorable environmental conditions; C. caryae mortality increased with the addition of the pheromone. The results of this study highlight a potential new avenue for microbial control in field conditions targeting the use of entomopathogenic nematodes. With increased efficacy, using entomopathogenic nematodes will reduce reliance on conventional management methods in pecan production, translating into more environmentally acceptable practices.