Background to the AMBER project
Plant pests cause serious problems for growers of horticultural crops. A wide range of damaging organisms affect crop production, including disease-causing microbes (fungi, bacteria, viruses,) arthropods (insects and mites), plant parasitic nematodes, slugs and snails. These pests reduce crop yields and quality, and if they are not controlled properly they result in serious financial losses for growers and inferior produce for customers. In the past, growers relied heavily on synthetic chemical pesticides for pest control. However, stricter regulations on pesticide safety have resulted in many chemical products being withdrawn from sale, while additional problems have been caused where pest and diseases have evolved resistance to some pesticides. Effective pesticides are now in short supply.
The UK protected edibles and ornamentals sectors – which together form an important part of the country’s agricultural economy – are committed to developing more sustainable methods of crop protection. Rather than relying just on pesticides, many progressive growers now use Integrated Pest Management (IPM), a system in which a range of different crop protection tools are combined together in complementary ways. The aim is to get effective pest control without harming the environment or causing problems for human health. IPM tools include resistant plant varieties, biological control agents, and cultural methods. Chemical pesticides are also used in IPM, but the aim is to use them only when necessary.
In recent years, new types of IPM tools called biopesticides have become available for growers. Biopesticides are based on micro-organisms, plant extracts and other natural compounds such as insect alarm pheromones. They pose minimal safety risk, which makes them very attractive in terms of operator safety and crop residue issues. In Europe now, as many biopesticides are being approved for use as conventional chemical pesticides, and the market is growing rapidly.
Biopesticides have sometimes been treated as straight replacements for conventional chemical pesticide, although this would be a mistake. Although biopesticides have many attractive properties, they generally work more slowly than conventional pesticides, can have lower levels of efficacy, and they are more sensitive to environmental conditions. As a result, they require more knowledge on behalf of the grower to get the best out of them. All biopesticide products require government authorization, and part of the approval process involves demonstrating their efficacy in field trials. However, in everyday commercial practice, while some biopesticides work well, growers have found others to give inconsistent or poor results, and this is often to do with how they are applied and managed in IPM.
The aim of AMBER is to identify management practices that growers can use to improve the performance of biopesticides. At the moment we are working with a small, handpicked number of biopesticides, but the issues we are tackling can be applied to the many biopesticide products that will come onto the market in the future. A lot of the work in AMBER is being doing on commercial nurseries, backed up by experiments done in the lab or controlled environment rooms. By looking at biopesticide performance in a systematic way, we hope to develop some core principles that growers can use to optimise the use of biopesticides in IPM for their own particular needs.