Occurrence and insecticide susceptibility of the grain aphid Sitobion avenae in northern Mongolia

Abstract

A survey was carried out to determine the prevalence of Sitobion avenae (S. avenae) in the central agriculture zone of northern Mongolia (including Darkhan-Uul, Selenge, Tuv, and Erdenet aimags). Bioassays were used to assess the pest's susceptibility to three regularly used insecticides (deltamethrin, fenvalerate, and imidacloprid). DNA sequencing was used to look into the genotypes of codons 918 and 1014 of the Voltage-gated sodium channel (VGSC) gene in S. avenae. The findings revealed that in 2019, the population density of S. avenae was low in 159 fields and medium in 31, and the infestation rate was low in 73 fields, medium in 117 fields. Even at a concentration of 0.005%, high mortality rates (>84 per cent) of S. avenae nymphs were detected after 72 hours of exposure to the three insecticides, indicating that this pest was susceptible to all three insecticides tested. In our grain aphid samples, the pyrethroid resistance-causing mutations (M918L and L1014F) in the voltage-gated sodium channel were not detected.

Keywords

• sitobion avenae
• infestation
• insecticide susceptibility
• population density
• voltage-gated sodium channel