Population structure of the beetle pests Phyllodecta vulgatissima and P. vitellinae on UK willow plantations

Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol, UK.
Insect Molecular Biology (Impact Factor: 2.59). 09/2004; 13(4):413-21. DOI: 10.1111/j.0962-1075.2004.00501.x
Source: PubMed


Phyllodecta (= Phratora) vulgatissima and P. vitellinae (Coleoptera: Chrysomelidae) are important pests of willows and poplars. Their differences in host species preference may provide a non-chemical control strategy for pest control. However, little is known about population structure with respect to hosts, regions or seasons. Using five microsatellites, 850 P. vulgatissima and 1100 P. vitellinae individuals, comprising 17 and 22 UK samples, respectively, were genotyped. High diversity was observed at all loci. Migrant numbers exchanged per generation (Nm) were high (2.1-12.6 for P. vulgatissima and 0.9-12.2 for P. vitellinae), suggesting high genetic exchange between samples. Estimates of population differentiation (FST) and analyses of the data using Bayesian methods (Partition and Structure) showed little evidence of subdivision in relation to geography, sampling time or host.

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    • "Knowledge of the population dynamics and of its driving forces is crucial for forest management. For this purpose, molecular tools are increasingly and successfully used in population genetic studies of insect pests to infer ecological characteristics that are crucial for establishing management strategies, as, for example, the elucidation of long-range movement in the boll-weevil (Kim and Sappington, 2004), or the clarification of the host-plant's role as a potential barrier to colonization and spread in a Chrysomelid pest of willows (Batley et al, 2004). Moreover, identifying ecotypes or host races within the target pest species is central to the establishment of successful control programmes (Bourguet et al, 2000). "
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