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Interactions among phytophagous mites and naturally occurring and introduced predatory mites - HH2305SSF

The objective of this research is to determine the pattern of feeding relationships in a system that includes two species of phytophagous (pest) mites, and naturally occurring and released predatory mites. Feeding patterns are likely to include consumption of one predator by another. This question of the interactions between and within trophic levels in a multi-predator system is a generic one, relevant to perennial crops in particular, but also to a wide range of horticultural crops. The model crop is strawberry grown under Spanish tunnels; the phytophagous mites are the two serious pest species Tetranychus urticae and Phytonemus pallidus, and the predatory mites are the naturally occurring species Typhlodromus pyri and Neoseiulus californicus, and the introduced species Neoseiulus cucumeris and Phytoseiulus persimilis. A multiplex PCR technique will be developed to enable us to identify the species of predatory mites present and the prey they have consumed, from individual predator samples. Predator-prey and predator-predator interactions will be determined in multiple predator systems in both laboratory and field experiments. The data collected will be used to develop a temporally dynamic semi-quantitative food web for mites in strawberry plantations; this will provide the sound knowledge base needed to define optimal intervention strategies for managing pest mite populations in different field situations. This ecological information will substantially enhance our ability to develop sustainable and cost effective management strategies for pests in UK horticulture. This meets MAFF’s Policy Objective to reduce pesticide use in the horticultural sector.In addition, the project will also aim to initiate preliminary modelling investigations on the dynamics of foliar pathogen-BCA (biocontrol agent) populations in order to predict the likelihood of successful biocontrol for a given characteristics of a particular biocontrol systems.
The overall aim of the project is to determine the feeding interactions among phytophagous mite species and naturally occurring and introduced predatory mite species. This will provide the underlying biological understanding needed to inform the development of optimised mite pest management strategies. The specific scientific objectives required to achieve this are:1. To develop statistically based methodologies for spatial and temporal sampling of phytophagous and predatory mites in strawberry plantations as a basis for the construction of a semi-quantitative food web.2. To develop the molecular tools to enable the determination of prey DNA in the predator gut, and the identity of the predator itself, from single mite samples.3. To develop a temporally-dynamic, semi-quantitative food web encapsulating relationships between phytophagous mites, and introduced and naturally-occurring predatory mites including consumption of one predator species by another. 4. To elucidate implications of relationships in food webs for practical mite management decision-making in strawberry-growing. 5. To conduct initial exploitory modelling studies on biological control of foliar pathogens.
Project Documents
• Final Report : Interactions among phytophagous mites and naturally occurring and introduced predatory mites   (1050k)
Time-Scale and Cost
From: 2001

To: 2004

Cost: £326,517
Contractor / Funded Organisations
Horticulture Research International
Biological Control              
Organic Farming              
Pest Control              
Plant diseases              
Fields of Study