Effects of Contact and Ingestion Exposure to Formulated CheckMate® LBAM-F and Unformulated LBAM Mating Pheromones on Adult Worker Honeybees, Apis mellifera (Hymenoptera: Apidae)

Abstract

ABSTRACT Acute 7-day toxicity tests evaluating adverse effects from contact and ingestion exposure to light brown apple moth (LBAM) pheromones and time-released microencapsulated LBAM pheromones in CheckMate® LBAM-F (Checkmate) were conducted on newly emerged honeybees (less than 24 h old). Contact studies exposed bees to 1× and 10× the CheckMate label application rate. Ingestion studies exposed bees to CheckMate formulations, and active (pheromone) ingredients (a.i.) at 0.1%, 1.0%, and 10% concentrations by weight in solid food. Bees ingested approximately 39% of their body weight during the tests. Mortality ranged from 2–10% in three of four contact and ingestion exposure trials. Trial 1, which utilized a different feeding design, showed higher mortality in both control and test replicates (9–28%). One-way ANOVA tests indicated no significant difference in mortality between control and treatment replicates in the four trials. Bees were subjected to one-time CheckMate contact exposures of up to 0.49 mg/kg-bee, and average pheromone and formulation ingestion exposures of up to 56 (0.1%), 611 (1.0%), and 6,282 (10%) mg/kg-bee-day. LBAM pheromones and microencapsulated pheromones proved to be non-toxic to honeybees when sprayed with 10× the field application rate, or when ingested in food at concentrations of up to 10% by weight.