Laboratory Evaluations of Insecticides Against Carmine Spider Mites on Cotton, 1984

Abstract

Abstract A completely randomized 2 factor factorial experiment was conducted in the laboratory to determine the effectiveness of an organophosphate, Azodrin, and a synthetic pyrethroid, FMC 54800, against adult female carmine spider mites under different constant temperatures. The mites were collected from cotton fields in the College Station, Texas area and reared on cotton seedlings for 6 mo prior to beginning the study. Individual cotton plants were grown to the second true leaf stage and were then infested with the cultured mites. The method of infestation consisted of clipping a leaf from a cotton seedling and transferring it, and the mites on it, to a test plant. The infested plants were held 48 h in a temperature cabinet to acclimate the mites to the test conditions (i.e. constant 26.5 or 32°C, 65% relative humidity and a 14:10 h fluorescent lamp photo: scotopha.se). Following a pre-treatment count of adult female mites, the insecticides were applied to the plants with a modified hand held sprayer calibrated (at 25 psi) to deliver ca. 6 gal per acre. At 72 h post-treatment, the plants were inspected for the presence of live mites to determine the efficacy of the pesticides. The experiment consisted of 4 replications of each treatment combination with 5 mite infested plants per replicate.