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Reliable identification of Aphidiinae species (Braconidae) is a prerequisite for conducting studies on aphid-parasitoid interactions at the community level. However, morphological identification of Aphidiinae species remains problematic even for specialists and is almost impossible with larval stages. Here, we compared the efficiency of two molecular markers [mitochondrial cytochrome c oxydase I (COI) and nuclear long wavelength rhodopsin (LWRh)] that could be used to accurately identify about 50 species of Aphidiinae that commonly occur in aphid-parasitoid networks in northwestern Europe. We first identified species on a morphological basis and then assessed the consistency of genetic and morphological data. Probably because of mitochondrial introgression, Aphidius ervi and A. microlophii were indistinguishable on the basis of their COI sequences, whereas LWRh sequences discriminated these species. Conversely, because of its lower variability, LWRh failed to discriminate two pairs of species ( Aphidius aquilus, Aphidius salicis, Lysiphlebus confusus and Lysiphlebus fabarum). Our study showed that no unique locus but a combination of two genes should be used to accurately identify members of Aphidiinae. [ABSTRACT FROM AUTHOR]

We believe that approaches to landscape modification should explicitly include farmers, given their understanding of landscape management practices, and consider climate change, so that the landscapes are designed for future environmental conditions. Climate change is an existential threat to farmers and current patterns of arable agriculture, leading to increases in the variability of agricultural productivity and crop failure. The performance of many of the crops that are currently highly productive will decline significantly and the geographical envelopes within which these crops can be grown are expected to shift northwards in Europe. Farmers will likely be faced with a choice: either leave farming or modify the crops that are grown, adopting new cultivars or species able to be cultivated profitably under future climatic conditions. We hypothesised that farmers do not adopt new crops or cultivars individually but use crops within sequences, called rotations, which are agronomically well understood. We know from past research that changes to rotations will lead to changes in biodiversity and the ecosystem services furnished by farmland, both within a field and at landscape scales. Here, we show how we might: use farmer knowledge of crop agronomy to propose future crop rotations in the light of climate change predictions; model these crop rotations to estimate likely effects on economy, biodiversity and ecosystem services; and validate these predictions through empirical study in regions where the rotations are already used. A workflow of co-development would have the benefit of generating practical rotations built on farmer knowledge and demonstrate empirically the predicted economic and ecological effects, markedly increasing the likely credibility of the results for farmers. Such a methodology has the potential to transform future sustainable agricultural landscapes. [ABSTRACT FROM AUTHOR]