1.
Virus Yellows can be found in practically every sugar beet field, and without careful management of the aphid vectors of the viruses, can spread across entire fields. This can result in up to 50% yield loss, a level which is intolerable to growers and can threaten the viability of their future of sugar beet growing.
New variety types are being developed and tested through BBRO’s Project Goliath and these can be expected to be more tolerant of the viruses. However, there is no evidence or claims to date of varieties which are more resistant to aphids or actively limit the spread of VY. Therefore, it will still be important to control the spread of aphids as part of an integrated programme for VY management.
This project develops a lot of areas in which BBRO is already investigating to speed up the development and deployment of IPM within sugar beet for VY/aphid management.
Neonicotinoid seed treatments, used widely between 1994 and 2018, provided effective VY control and limited the spread of migratory winged aphids and, therefore, prevented widespread VY epidemics. Since withdrawal of these chemicals, foliar aphicides have become the only other viable option for reliable aphid management in sugar beet. However, there is more of a lag in control of aphids with this approach and the focus is instead in reducing secondary spread of virus.
Each year BBRO delivers an aphid monitoring survey during the spring to guide growers on local aphid levels and progression of the migration. This acts as a guide for growers to monitor their crops and see if their fields have reached the population threshold for control (e.g. one green wingless aphid per four plants up to the twelve leaf stage) at which they are advised to treat the crop with a foliar aphicide. As of 2024, two aphicides are registered in sugar beet; flonicamid, sold as Teppeki by Certis Belchim Crop Protection or Afinto by Syngenta and acetamaprid, a neonicotinoid, marketed as InSyst by Certis Belchim. Both currently offer effective control of aphids. However, they require broadacre spraying and these can potentially have indirect impacts on natural predators of aphids also on the crop. M. persicae is also known to develop resistance to insecticides and therefore these may not offer complete or long-term aphid management into the future.
Considering the limitations of relying on chemical seed treatments or broad-acre sprays, and the drawbacks these pose to the environment, BBRO is keen to develop and investigate commercially adaptable IPM strategies for aphid control in future sugar beet crops. This will include the virus tolerant or resistant varieties, but there are other techniques which warrant investigation. These are outlined below and illustrate a range of work packages which BBRO will deliver to take advantage to understand how we can start developing integrated aphid management approaches in sugar beet.
Various IPM approaches have been trialled on a small scale by BBRO over the last four years. We have seen some promising results, so it is now important to test these methods on a wider scale to see how they perform over a more diverse range of locations. The majority of this research cannot be undertaken in small-plot, randomised trials due to the influence of the local landscape which is required, and therefore a lot of monitoring work is required.
We propose to test the following different IPM methods using a range of approaches:
A. Attractants
Offer more attractive host plants to the aphids through the sowing of brassica and/or potato strips within beet fields. These crops are known to pull aphids away from sugar beet and provide areas for more targeted aphid management
B. Beneficials
Monitor farms with pre-existing features where beneficial insects will over-winter and see when beneficial insects appear into crops. Local and/or in-field VY incidence will then be recorded in the summer to see whether there is any influence on VY management.
C. Camouflage
1. Dyes to artificially cover the soil with a colour which is not appealing to migrating aphids, thus limiting the number of winged aphids alighting into crops.
2. Cereal Companion cropping. Further investigate the role of cereal companion crops to provide an alternative method to confuse aphids and prevent them landing and feeding on sugar beet.
D. Deterrents/Repellents
Increasingly, evidence is being gathered across Europe relating to the roles of volatile organic compounds (VOCs) in host finding in aphids and how manipulating the odour of a crop can prevent aphids infesting sugar beet. We will look at a commercial product (Agriodor) which is claimed by the manufacturer to repel aphids and delay their buildup.
The research is proposed as four individual work packages;
- Attractants and Alternative hosts
- Beneficial insects
- Camouflage cropping
- Deterrents and Repellents
These areas will also form the knowledge exchange strategy to the UK grower base: ‘BBRO’s ABCD of Aphid IPM’. Using our website, podcasts, British Sugar communications and grower events we will keep growers up-to-date with the findings to ultimately produce a practicable and forward looking IPM strategy.
