Impacts of novel control strategies for Spotted Winged Drosophila on ecosystem services and crop production in raspberries
Lead Research Organisation:
University of Reading
Department Name: Sch of Agriculture Policy and Dev
Abstract
Project motivation and aims (<300 words):
Raspberries are an increasingly important high value crop in the UK with opportunities to increase the market in the near future. Raspberry production is under threat however from a number of key pests including spotted winged drosophila (Drosophila suzukii, SWD) but chemical control options (primarily, cyantraniliprole, spinosad and lambda-cyhalothrin) are limited with restrictions on use, and repeated insecticide applications are unsustainable and could cause future insecticide resistance of SWD. Even with current insecticide control options, SWD control breaks down, particularly towards the end of the season when populations increase. Insect mesh is increasingly being employed to limit the impact of SWD by reducing numbers that enter the crop from neighbouring habitats. However, this novel control strategy has implications for crop pollination and pest control by excluding wild pollinating insects and natural enemies. It may also effect poly-tunnel climatic conditions increasing risks of disease and crop loss. If insect mesh is to become the mainstay of SWD control then it is crucially important to understand what impact this may have for pollination, biocontrol and crop production and we need to identify effective methods of integrating mesh into raspberry production which maximize control of SWD but minimize negative effects on ecosystem services.
The risks and benefits of incorporating insect mesh to control SWD has been identified as a key knowledge gap by the industry and so the aim of this project is to quantify its effects on raspberry production and identify how it can be integrated into management systems to maximise the benefits to the growers. The specific Research Objective of this project include:
1. Test the effectiveness of insect mesh to provide economically acceptable control of SWD in raspberries.
2. Investigate the potential impacts of insect mesh on insect pollination, natural pest control, disease and the tunnel environment and resulting fruit yield and quality.
3. Field test different management practices for integrating insect mesh into raspberry production in order to identify an optimal strategy that is economically feasible and delivers effective IPM.
Programme of research (<300 words):
Using Berryworld's extensive network of raspberry growers, we will implement a replicated trial to address our three research objectives. Working closely with growers we will compare poly-tunnels which have installed insect mesh to control SWD with those that have not. Treatments will be replicated within and across different farms allowing us to understand the impacts of insect mesh across a number of different geographic and management contexts.
Objective 1: Testing effectiveness of insect mesh in controlling SWD. Throughout season 1 and 2, SWD populations will be surveyed using standard semiochemical monitoring traps inside and outside insect mesh and control poly-tunnels. The impact of SWD on the crop will be measured using flotation and emergence tests. This allows us to quantify the direct effects of insect mesh on SWD fruit damage, and by tracking SWD populations, we will identify how well mesh prevents SWD entering the crop throughout the growing season.
Objective 2: Understanding impacts of insect mesh on other ecosystem services. In season 1 and 2, pollination services (transect walks), natural pest regulation (bait cards) and the tunnel environment (temperature and humidity) will be compared between insect mesh and control tunnels. Levels of fungal disease in the fruit, and final crop output will be measured to understand if insect mesh compromises production by affecting these other key factors.
Objective 3: Developing and testing optimal strategies for incorporating mesh into sustainable raspberry production. Informed by Objectives 1 and 2, in season 3 and 4, difference SWD control strategies will be compared including raising and low
Raspberries are an increasingly important high value crop in the UK with opportunities to increase the market in the near future. Raspberry production is under threat however from a number of key pests including spotted winged drosophila (Drosophila suzukii, SWD) but chemical control options (primarily, cyantraniliprole, spinosad and lambda-cyhalothrin) are limited with restrictions on use, and repeated insecticide applications are unsustainable and could cause future insecticide resistance of SWD. Even with current insecticide control options, SWD control breaks down, particularly towards the end of the season when populations increase. Insect mesh is increasingly being employed to limit the impact of SWD by reducing numbers that enter the crop from neighbouring habitats. However, this novel control strategy has implications for crop pollination and pest control by excluding wild pollinating insects and natural enemies. It may also effect poly-tunnel climatic conditions increasing risks of disease and crop loss. If insect mesh is to become the mainstay of SWD control then it is crucially important to understand what impact this may have for pollination, biocontrol and crop production and we need to identify effective methods of integrating mesh into raspberry production which maximize control of SWD but minimize negative effects on ecosystem services.
The risks and benefits of incorporating insect mesh to control SWD has been identified as a key knowledge gap by the industry and so the aim of this project is to quantify its effects on raspberry production and identify how it can be integrated into management systems to maximise the benefits to the growers. The specific Research Objective of this project include:
1. Test the effectiveness of insect mesh to provide economically acceptable control of SWD in raspberries.
2. Investigate the potential impacts of insect mesh on insect pollination, natural pest control, disease and the tunnel environment and resulting fruit yield and quality.
3. Field test different management practices for integrating insect mesh into raspberry production in order to identify an optimal strategy that is economically feasible and delivers effective IPM.
Programme of research (<300 words):
Using Berryworld's extensive network of raspberry growers, we will implement a replicated trial to address our three research objectives. Working closely with growers we will compare poly-tunnels which have installed insect mesh to control SWD with those that have not. Treatments will be replicated within and across different farms allowing us to understand the impacts of insect mesh across a number of different geographic and management contexts.
Objective 1: Testing effectiveness of insect mesh in controlling SWD. Throughout season 1 and 2, SWD populations will be surveyed using standard semiochemical monitoring traps inside and outside insect mesh and control poly-tunnels. The impact of SWD on the crop will be measured using flotation and emergence tests. This allows us to quantify the direct effects of insect mesh on SWD fruit damage, and by tracking SWD populations, we will identify how well mesh prevents SWD entering the crop throughout the growing season.
Objective 2: Understanding impacts of insect mesh on other ecosystem services. In season 1 and 2, pollination services (transect walks), natural pest regulation (bait cards) and the tunnel environment (temperature and humidity) will be compared between insect mesh and control tunnels. Levels of fungal disease in the fruit, and final crop output will be measured to understand if insect mesh compromises production by affecting these other key factors.
Objective 3: Developing and testing optimal strategies for incorporating mesh into sustainable raspberry production. Informed by Objectives 1 and 2, in season 3 and 4, difference SWD control strategies will be compared including raising and low