Evaluation of phloxine B as a possible control agent against citrus thrips (Thysanoptera: Thripidae).
We evaluated the toxicity of phloxine B photoactive dye combined with a cane molasses bait against citrus thrips, Scirtothrips citri (Moulton). Laboratory bioassays conducted under artificial light showed that thrips mortality followed a log-dose probit-response model with an estimated LC50 of 0.0079% dye. Diluted cane molasses plus 0.01% phloxine B then was used as a standard for comparison of eight additional baits, including three formulations of concentrated citrus peel liquor (CCPL1-3). Citrus thrips mortality ranked highest to lowest with CCPL1 and CCPL3 > CCPL2, Mo-Bait and cane molasses > concentrated beet molasses, concentrated cane molasses, hemicellulose extract, and whey. Several commercial surfactants were tested to see if their addition to the standard increased efficacy. Hyper-Active, Kinetic, and Tween 60 at 1% and Cohort, Hyper-Active, Kinetic, and Silwet at 0.25% when added to the standard, reduced citrus thrips mortality, whereas Tween 60 and Dyne-Amic at 0.25% had no effect. Cane molasses with one or 5% phloxine B dye and CCPL1 with 1% dye were sprayed on citrus trees and allowed to weather in the field. Laboratory bioassays conducted after leaves had weathered for up to 8 d indicated that bait-dye toxicity was persistent. Possible use of the bait-dye mixture in commercial control of citrus thrips is discussed.
Tollerup
K
K
Department of Entomology, University of California, Riverside, CA 92521, USA. kris@citrus.ucr.edu
Morse
J G
JG
D000821:Animal Feed; D000818:Animals; D002241:Carbohydrates / Q000032:analysis; D019587:Dietary Supplements; D010697:Eosine I Bluish / Q000008:administration & dosage / Q000494:pharmacology*; D007300:Insect Control / Q000379:methods*; D007313:Insecta / Q000187:drug effects*; D007306:Insecticides / Q000008:administration & dosage / Q000494:pharmacology*; D007928:Lethal Dose 50; D008027:Light; D008965:Molasses; D013501:Surface-Active Agents / Q000494:pharmacology
D002241:Carbohydrates; D007306:Insecticides; D013501:Surface-Active Agents; D010697:Eosine I Bluish