Quantification of enzymes related to insecticide resistance in Bemisia tabaci from the state of Sinaloa

Abstract

The whitefly Bemisia tabaci (Gennadius) is one of the most invasive pests and causes direct damage to crop by feeding on the sap and indirect damage by being a vector of more than 100 phytopathogenic viruses. At present its control is based on the use of chemical insecticides, because the populations have been constantly subjected to a high selection pressure. An alternative that contributes to understanding the origin of resistance in a population are biochemical tests, which show the parameter of the detoxifying enzyme present. The objective of the present work was the quantification of these enzymes in B. tabaci in the three main solanaceae producing areas of the north (Guasave, Sinaloa de Leyva, Mochis), center (Culiacán, Navolato, Elota) and south (Concordia, Rosario, Esquinapa) of the state of Sinaloa. Whitefly adults were collected at these sites and the enzymatic levels of α and β esterases, glutathione S-transferases, aceticolinesterases and oxidases were determined, additionally a susceptible laboratory line was used as a reference. The enzymes with the highest presence were α-esterases, β-esterases and oxidases, followed by glutathione S-transferases and acetylcholinesterase. Therefore, it is concluded that resistance to insecticides in B. tabaci in the state of Sinaloa is due to the high content of α - β-esterases and oxidases, while acetylcholinesterase is not a relevant mechanism in the populations of this producing region.