CUTTER WORMS (Agrotis ipsilon) SUSCEPTIBILITY (LEPIDOPTERA: NOCTUIDAE) TO DOSE OF INSECTICIDE OF DIFERENT TOXICOLOGYCAL GROUPS IN CERRO PUNTA, PROVINCE OF CHIRIQUI. PANAMA. 2003.

Abstract

With the objetive to determine the susceptibility levels of populations of cutter worms to dose of insecticides of different toxicologycal groups used in the potato and vegetables cultivation in Cerro Punta, were accomplished bioassays using the technique of application topic, the one which consisted of the application of a microlitre of solution insecticide - acetone on the protorax of larva of Agrotis ipsilon. The mortality data were taken to 24 hours after applied the treatments of insecticide. There were evaluated the following insecticides: indoxacarb, cipermethrin, permethrin, clorpirifos, meta-midofos, carbofuran, and endosulfan. The mortality data were analyzed by computerized program PC-Probit, and were obtained the DL₅₀ and the 95% fiducial limits, DL₉₅. Response dose - mortality lines and the predictable equation of the form y = a + bx. It was accomplished the regression analysis of the mortality data, obtaining an r² = 0.65 to 0.97 with a significance P<0.05. The value of the test of lack of fit of the group of data was between 0.0404 and 1.073, being less tan the tabular, being adjusted the data  (P = 0.05). The indoxacarb, obtained the less DL₅₀ and DL₉₅, of 1.794µg/g and 5.993µg/g, respectively, followed by the cipermethrin with DL₅₀ of 4.575 µg/g and DL₉₅ of 35.522 µg/g. According to these results the population Agrotis ipsilon treated with indoxocarb was the most susceptible followed by cipermethrin.