Biochemical resistance to insecticide in Bemisia tabaci field population from Burkina Faso, West Africa

---

Résumé

Insecticides are commonly used in greenhouses or fields to control Bemisia tabaci populations
leading to rapid evolution of resistance that make treatments inefficient. This resistance can be mediated by
molecular and/or biochemical mechanisms. Here, we
propose to determine the detoxifying enzymes involved
in B. tabaci resistance and to establish the relationship
between the enzymatic activity and the values of Lethal
Concentrations 50 (LC50). Susceptibility to deltamethrin, acetamiprid and chlorpyrifos-ethyl was assessed,
using leaf dip method populations sampled from four
(4) sites in Burkina Faso in 2017. Detoxifying enzymes
activities including non-specific α-esterases, Para Nitro
Phenyl Acetate esterases, oxidases (cytochrome P450)
and Glutathione -S-Transferases (GSTs) were measured
on single B. tabaci (N = 50) from each test locality and
compared with the susceptible strain. In all sites,
B. tabaci demonstrated multiple resistance phenotypes.
Variation in detoxifying enzyme activities was observed
within B. tabaci populations. Elevated levels of nonspecific α esterase and GSTs were widespread, suggesting multiple resistance mechanisms occurred within
B. tabaci populations from this country.

Mots-clés

Bemisia tabaci . Insecticide resistance . Detoxificant enzymes . Burkina Faso