Résumé
The English grain aphid, Sitobion avenae, is a significant agricultural pest in Europe that damages cereal crops by feeding on the grain and by transmitting viruses (e.g., Luteovirus mavhordei or Luteovirus pashordei species). In recent years, controlling aphids has become more challenging for farmers because of the EU-ban on neonicotinoid insecticides and the emergence of resistance to pyrethroid insecticides in a clonal lineage of S. avenae. However, the ability to survive insecticides has come with multiple pleiotropic effects on aphid behaviour and fitness, suggesting that virus transmission efficiency could also be affected. This study tested Irish S. avenae clones resistant or susceptible to pyrethroids for their ability to transmit isolates of Luteovirus pashordei (i.e., BYDV-PASFC) and Luteovirus mavhordei (i.e., BYDV-MAVSac). The results showed that the transmission rates of BYDV-PASFC were very low, ranging from 0% to 12%, while BYDV-MAVSac was more efficiently transmitted (from 26% to 40%). Furthermore, the study found no differences in transmission efficiency between the insecticide-resistant and -susceptible aphid clones, suggesting no genotype or fitness-related impact of insecticide resistance on BYDV transmission efficiencies.