Toxicity of Surfactants and Surfactant-Insecticide Combinations to the Bollworm, Tobacco Budworm, and Pink Bollworm1234

Abstract

The effectiveness of various surfactants in the control of larvae of the bollworm, Heliothis zea (Boddie), tobacco budworm, H. virescens (F), and pink bollworm, Pectinophora gossypiella (Saunders), was evaluated. When cotton bolls containing diapausing pink bollworm larvae were dipped in Triton® X-150 (ethoxylated alkylphenol blends with organic sulfonates) or Triton® X-100 and X-155 (ethoxy1ated alkylphenols) at 2 or 5%, moth emergence was reduced by 89% or more compared with emergence from untreated bolls, and Tween® 65 and 85 were more effective than Tween® 60, 61, 80, or 40 (allethoxylated sorbitan esters) at 2 or 5%. In laboratory tests with foliar sprays at 2.5 kg per hectare, ethoxylated tridecyl alcohol containing mole ratios of 15:1 of ethylene oxide to alcohol killed more bollworms than the 3:I mole ratio. Retzolate 58 (ammonium salts of ethoxylated alcohol sulfates) at 4.5 kg per hectare alone killed 40% or more bollworm and tobacco budworm larvae. Also when Retzloff DRS 22 or DRB 203 (polymeric phenolic resins) at 2.2 kg per hectare were added to carbaryl at 2.2 kg per hectare and used as a foliar spray on both dry and wet leaf surfaces, they killed more bollworm larvae than the insecticides alone. In field-cage tests, Rerzamide LAX and Retzamide COA (alkanolamides) and Retzloff DTG 62 (ethoxylated polyols) at 2.2 kg per hectare, each combined with DDT at 2.2 kg per hectare or carbaryl at 2.2 kg per hectare, killed more tobacco budworms than the insecticides alone.