Alfalfa Seed Production Insecticide Efficacy in 2014

Abstract

An experiment to evaluate the efficacy various insecticide treatments for control of alfalfa seed production insect pests was conducted at the University of California Desert Research and Extension Center on a stand of CUF-101 alfalfa on beds of 40 inch centers. The experimental design was RCB using four replicates with nine insecticide treatments and an untreated check. Plots were 50 ft wide (15 beds) and 70 ft long; one non-treated buffer bed between plots and a 5-ft non-treated buffer between replicate blocks. Insecticide treatments were applied on 28 May and 11 June 2014 at the rates specified in the tables. Insecticide treatments were broadcast sprays applied using a Lee Spider Spray Trac spray applicator equipped with 13 nozzles (TJ-60 11003VS) operated at 20 psi, and delivering 26 gpa in a 25-ft wide spray swath. Hasten, a modified vegetable oil surfactant (Wilber-Ellis Company) was added as a surfactant to each insecticide tank mixtures at a concentration of 0.25% vol/vol. To establish insect population uniformity, the entire field was sprayed with Dibrom 8 at 1.0 pt/acre on 29 Apr. The pre-treatment (PT) insect population data were collected on 27 May 2014; 1-day prior to treatment (1-DPT). Post-treatment samples, after the first series of insecticide treatments, were taken on 30 May, 4, 6, and 10 Jun or 2, 7, 9, and 13 days after treatment one (DAT1) and post-treatment, after the second series of insecticide treatments, were taken on 13, 18, 20, and 25 June or …