Decline in landscape complexity owing to agricultural intensification may affect biodiversity, food web complexity and associated ecological processes such as biological control, but such relationships are poorly understood. Here, we analysed food webs of cereal aphids, their primary parasitoids and hyperparasitoids in 18 agricultural landscapes differing in structural complexity (42 -93% arable land). Despite little variation in the richness of each trophic group, we found considerable changes in trophic link properties across the landscape complexity gradient. Unexpectedly, aphid -parasitoid food webs exhibited a lower complexity (lower linkage density, interaction diversity and generality) in structurally complex landscapes, which was related to the dominance of one aphid species in complex landscapes. Nevertheless, primary parasitism, as well as hyperparasitism, was higher in complex landscapes, with primary parasitism reaching levels for potentially successful biological control. In conclusion, landscape complexity appeared to foster higher parasitism rates, but simpler food webs, thereby casting doubt on the general importance of food web complexity for ecosystem functioning.

Understanding how climate change might influence the distribution and abundance of crop pests is fundamental for the development and the implementation of pest management strategies. Here we present and apply a modelling framework assessing the non-linear physiological responses of the life-history strategies of the Mediterranean fruit fly (Ceratitis capitata, Wiedemann) to temperature. The model is used to explore how climate change might influence the distribution and abundance of this pest in Europe. We estimated the change in the distribution, abundance and activity of this species under current (year 2020) and future (years 2030 and 2050) climatic scenarios. The effects of climate change on the distribution, abundance and activity of C. capitata are heterogeneous both in time and in space. A northward expansion of the species, an increase in the altitudinal limit marking the presence of the species, and an overall increase in population abundance is expected in areas that might become more suitable under a changing climate. On the contrary, stable or reduced population abundances can be expected in areas where climate change leads to equally suitable or less suitable conditions. This heterogeneity reflects the contribution of both spatial variability in the predicted climatic patterns and non-linearity in the responses of the species’ life-history strategies to temperature.

Global trade of plants and plant products facilitates the international movement of pests. The introduction of new pests in an area may have huge economic consequences for local plant production, and should be avoided. The European Union (EU) imports large quantities of fresh fruit from all over the world, which could be a pathway for exotic pests. This review aimed to identify pests not yet present or regulated in the EU that may enter the territory with the fruit trade and damage fruit production in Europe. Pests of Vaccinium (blueberry), apple, grape, orange and mandarin were screened to assess the likelihood of their being associated with these fruit, their impact, their geographical distribution, whether they are intercepted in trade and whether they are spreading or emerging. They were further ranked to produce alert lists of 30 to 36 pests for each fruit species. These lists are presented as well as other findings on contaminants and newly introduced pests. Datasheets on those pests were prepared and are available as supporting information to this article as well as in the EPPO Global Database (https://gd.eppo.int/). This work within the EU project DROPSA aimed to raise the awareness of importers and regulatory authorities to the potential risk of introducing pests with the fruit trade.

No abstract

This pest survey card was prepared in the context of the EFSA mandate on plant pest surveillance (M-2017-0137) at the request of the European Commission. Its purpose is to guide the Member States in preparing data and information for Geosmithia morbida and Pityophthorus juglandis surveys. These are required to design statistically sound and risk-based pest surveys, in line with current international standards. Geosmithia morbida and its vector P. juglandis are clearly defined taxonomic entities and the combined activity of the fungus and the insect causes the disease complex thousand canker disease on the plant genera Juglans and Pterocarya. The pest and its vector originate in North America and currently have a restricted distribution in the EU, limited to the northern parts of Italy. However, they are potentially able to become established everywhere in the EU where their host plants occur. Currently, the spread capacity of P. juglandis is unknown, but the insect vector may cover large distances by passive dispersal or human-assisted spread. Risk locations include entry points (e.g. seaports, airports), loading stations, storage facilities and wood processing companies that deal with heat-treated wood, bark or woodchips of the genera Juglans and Pterocarya originating from countries where the fungus and its vector occur. Trapping is the recommended method for detecting the vector in the early stages of an epidemic. Following insect trapping, a specific tree inspection should be carried out, looking for external symptoms (e.g. penetration and exit holes, cankers and wilting). The trapping should start when the mean air temperature exceeds 18°C. Morphological identification of the pathogen and its vector should be performed by experts. Molecular assays are also available for both fungal and vector identification.