Lettuce and baby leaf salads: Investigation into control measures for Silver Y moth and caterpillars

The Problem:

Damage caused by the Silver Y moth and other caterpillar species can result in unacceptable leaf damage in outdoor baby leaf and lettuce crops, where there is zero tolerance for either the presence of, or visible damage from, these pests.  Loss of active ingredients has left the industry with a limited list of insecticides which are not effective and all have long harvest intervals. This is resulting in poor control of these pests in UK crops. The overall aim of the project is to provide growers of lettuce and baby leaf salad crops with the tools (decision-support and control methods) to improve overall control of silver Y moth and other pest caterpillars.  A relatively large and diverse project consortium has been assembled.  This will maximise the opportunity for collecting meaningful information that is of direct relevance to growers.  The consortium includes research organisations, consultants, growers and members of the wider industry (e.g. provision of monitoring systems). 

The focus will be on novel control agents (insecticides and bioinsecticides), some of which have been identified in the SCEPTRE project, and on the use of monitoring approaches to improve the identification of potential problems and aid decision-making with regard to treatment.  The project will also evaluate the performance and utility of a novel system for monitoring pest moths using pheromone traps.  The project team will investigate other monitoring and control mechanisms which may be effective and the consortium will make recommendations for how they might be developed through future research, as additional detailed investigation is likely to be outside the scope of this project.  Whilst most pesticide efficacy trials will be undertaken on research sites, the majority of pest and crop monitoring will be undertaken on commercial holdings.  If there are opportunities to undertake small evaluation trials on commercial holdings, these will be taken. 

All project participants and other interested parties will be invited to a ‘brainstorming’ workshop at the start of the project and this will also include a short demonstration on the novel pheromone trapping system.  The output from the project will be presented at at least one industry meeting.  In addition to the annual and final reports, the consortium will produce at least one article for HDC News and a factsheet on an improved strategy for control of silver Y moth and other caterpillars.

Benefits to industry:

The proposal has been submitted in response to a call by the HDC to carry out studies to investigate potential mechanisms for the control of Silver Y moth (Autographa gamma) in Baby Leaf crops and other caterpillar species in outdoor lettuce. The benefits of a successful outcome to the project will be improved quality of crops marketed and fewer crop losses and rejections.  The aim is to deliver the results back to the growers by engaging them fully in the project from the beginning.  In addition, the wider industry will be informed through the annual and final reports, articles in HDC news, a factsheet and at least one open industry meeting. 

Whilst the project will focus on pests of baby leaf and salad crops, it will have implications for caterpillar control on other crop types, both with regard to control methods and the approaches used to monitor the pest species and make decisions about control.

Aims: 

The overall aim of the project is to provide growers of lettuce and baby leaf salad crops with the tools (decision-support and control methods) to improve overall control of silver Y moth caterpillars and other pest caterpillars. 

 Objectives:

1. Liaise with agrochemical companies and crop protection specialists to identify experimental conventional pesticides which may show efficacy in controlling caterpillars.

2. Consider the use of novel, approved or near market, biological control products which might be beneficial in reducing the risk of pesticide residues. 

3. Gather accurate and detailed data during the project by undertaking thorough assessments which will be statistically robust.

4. Carry out suitable, randomised and replicated, field trials in both baby leaf and lettuce crops to measure the efficacy of the chosen treatment regimes.

5. Develop a risk-based spray-decision-making system linked to trapping of moths and measure its efficacy, via field trials, against normal pest control practice.

6. Investigate other monitoring and control mechanisms which may be effective and make recommendations for how they might be developed through future research.

7. Engage and communicate with growers and other members of the industry.