Control of Early Season Insect Pests of Cotton with Insecticides Applied as Seed Treatments, Granular Formulations, and Foliar Sprays, 1984

Abstract

Abstract A small plot field study was conducted on the Plant Science Research Farm at Mississippi State, MS. Plots (4 rows × 45 ft) were planted to ‘Stoneville 825’ cotton on 22 May. The experiment was conducted as a randomized complete block with 10 replicates. Seed treatments were applied to seed by spraying evenly distributed samples on a belt sprayer. Granular applications were made with Gandy applicators, and in-furrow applications of Standak were made with a compressed air sprayer mounted behind the planter wheel. All foliar applications were made with a compressed air sprayer mounted on a Ford 5000 tractor. The sprayer was calibrated to deliver ca. 6.5 gpa total volume with 2 TX-4 nozzles per row. Foliar applications followed 2 different treatment regimes. Some of the treatments were initiated at the first true leaf (ITL) stage of plant growth with a total of 5 early season applications being made on weekly intervals. The alternative treatment regime was initiating early season applications at the pinhead square (PHS) stage of growth and making 4 early season applications on weekly intervals. After the first bloom stage of plant growth, the entire study area was oversprayed on weekly intervals to protect the influence of early season treatment effects. ITL treatments were made on 12, 20, and 27 Jun, and 4, 12, and 16 Jul. PHS treatments were made on 27 Jun, and 4, 12, and 16 Jul. All plots were oversprayed on 12 Jun with dimethoate (0.2 lb Al/acre) to prevent thrips from destroying the test. Subsequent oversprays were made on 20 and 24 Jul, 24, and 3, 13, 20, 22, and 28 Aug, 12, 20 and 28 Sep, and 3 Oct with fenvalerate (0.1 lb Al/acre) and azinphosmethyl (0.25 lb Al/acre) to protect the plots from Heliothis spp. and Anthonomus grandis.