Improving aphid and BYDV monitoring

Abstract

Aphids damage cereal crops either via direct feeding or by vectoring viruses such as barely/cereal dwarf virus (B/CYDV). These viruses cause leaf yellowing and stunt growth, posing an economic threat to global cereal production. The management of aphids was reliant on applications of neonicotinoid seed treatments until their ban in 2018.Foliar applications of pyrethroids replaced neonicotinoid applications, becoming the primary management tool, in 2020 they accounted for 83% of the insecticide-treated area in the UK (FERA 2021). The future effectiveness of pyrethroids has been called into question as populations of Sitobion avenea in Europe have developed resistance. Resistant populations of S.avenea are cited as the reason of reduced success managing BYDV in the UK (Dewar and Foster 2017). The application of pyrethorids is not governed by a pest management threshold, with 20% of growers questioned in 2020 applying pyrethorids upon first aphid sighting (AHDB 2020). However, the presence of an aphid within a field does not mean the field will be infected with B/CYDV (Holland et al., 2021). Only 5% of migratory aphids in France and the UK where infected with B/CYDV. An increased understanding of the risk of B/CYD posed by aphid populations is needed to better predict where virus risk is high and selectively target these areas. Alongside optimised insecticide applications other management strategies,such as tolerant/resistant varieties, need to be incorporated into an integrated pest management program. Recently tolerant barely and resistant wheat varieties have become commercially available in Ireland.

Description

The overall aim of this project is to develop a dynamic integrated pest management (IPM) programme to optimise the management of B/CYDV. This will be achieved by answering three main research questions: 
1.         Can aphid monitoring be used as a reliable decision support tool for B/CYDV?
2.         Identify the potential role of tolerant/resistant varieties in an IPM programme to manage B/CYDV. 
3.         Determine the effectiveness of novel and existing DSS at a farm scale using Tram line trials.