Insecticide susceptibility level and control failure likelihood estimation of Sub‐Saharan African populations of tomato leafminer: Evidence from Burkina Faso

Abstract

The South American tomato pinworm, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) is a leafminer species currently considered as one of the major pests of fresh tomatoes around the world. The species settled in north Africa in 2007, before being observed in the entire continent. Widespread insecticide use has led to the emergence of resistant populations in South America and Europe, but no large-scale insecticide resistance assessment has been performed in Sub-Saharan Africa so far. In this study, we collected T. absoluta larvae from locations widely distributed in Burkina Faso, where the pest was first detected in 2016. Acute toxicity of the all available molecules in Burkina Faso was evaluated in the laboratory on F1 individuals, including acetamiprid, abamectin, spinosad, cypermethrin, chlorpyrifos, λ-cyhalothrin, deltamethrin, and Bacillus thuringiensis. No LC50 differences among T. absoluta populations were highlighted, except for Bacillus thuringiensis. Insects were still highly susceptible to abamectin [LC50 < 0.4 mg/L; Control failure likelihood (CFL) = −25%], spinosad (LC50 < 0.6 mg/L; CFL = 25%) and chlorpyrifos-ethyl (LC50 between 254 and 458 mg/L; CFL = −15%), but were less susceptible to acetamiprid (CFL ranging from 72% to 91%), cypermethrin (CFL = 80%), λ-cyhalothrin (CFL =79%), and deltamethrin (CFL ranging from 51% to 66%), with LC50 values for these insecticides ranging between 100 and 525 mg/L. Pending a proper communication strategy, we hope this work could help producers avoiding the most inefficient active substances.

Integrated pest management options for the fall armyworm Spodoptera frugiperda in West Africa: Challenges and opportunities. A review

“…Since West Africa is lacking data on the resistance status of the fall armyworm to the available insecticide substances, we suggest the establishment of laboratories accredited to measure susceptibility and resistance to the major classes of pesticides in all areas where the fall armyworm is present. A similar suggestion has recently been made for another invasive pest, Tuta absoluta Meyrick (Sawadogo et al, 2020). A unique methodology should be followed and applied to populations collected from the main maize areas of West African.…”

“…-they are too expensive for a significant portion of smallholder farmers; -they lead to the selection of resistant populations of pests (as highlighted recently by Sawadogo et al [2020] in Burkina Faso); -they have adverse effects on non-target organisms (including natural enemies) (Desneux et al, 2007) and human health (Damalas & Eleftherohorinos, 2011).…”

Baseline Toxicity Data of Different Insecticides against the Fall Armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) and Control Failure Likelihood Estimation in Burkina Faso

“…This difference in susceptibility may be related to the frequency of insecticide applications, higher in vegetable crops than in cereals; maize was not treated with insecticides before the arrival of the fall armyworm in 2016 (Caniço et al 2020). Now, abamectin is becoming increasingly important in tomato production to control major pests such as mites and leafminer Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) in Burkina Faso (Sawadogo et al 2020;Son et al 2017Son et al , 2018.…”

Comparison of life‐history traits and oviposition preferences of Tuta absoluta for 12 common tomato varieties in Burkina Faso

“…Since 2008, it has been spreading rapidly over the African continent, particularly in the Maghreb countries, and was first discovered in Burkina Faso (northern region) in 2016 (Son et al ., 2017; Mansour et al ., 2018). Since then, chemical control has been favored, and most reports produced from the Agricultural Ministry describe cases of treatment failures and abandonment of production plots (Sawadogo et al ., 2020a, b). This is probably due to the ability of this insect pest to rapidly develop resistance to the different chemical molecules used (Roditakis et al ., 2018; Guedes et al ., 2019).…”