The complex phenomenon of decline in European oak is currently triggered by changing climatic conditions and their consequences like heavy rains, local floods and pest development. Especially, pathogens from Phytophthora genus profit from soil saturation with water. They are alien invasive species, which attack and severely damage fine roots. In drought conditions occurring in the subsequent year, many oaks die as they encounter problem with water uptake. Additionally, insect defoliators followed by oak mildew infections accelerate the level of tree mortality. Secondary insects, butt and root pathogens are usually the final cause of death of many oaks. More research is needed in the direction to determine (i) measurable factors (e.g. chlorophyll florescence) that can indicate that the process of tree decline has already started, (ii) the correlation between the root decay and the crown symptoms (scanners, software), (iii) which combination of stressors stimulate the best development of pathogens that lead to the high plant mortality and (iv) the difference between the mortality caused by the native and the invasive Phytophthora species.

Following a request from the European Commission, EFSA was tasked to periodically update its database of host plants of Xylella fastidiosa which was published in April 2015. An extensive literature search approach was used for updating the database in order to catch all new scientific developments published on the topic. Furthermore, the outputs of investigations conducted on host plants affected by X. fastidiosa in the Italian and French outbreaks were included. Literature screening and data extraction were performed using the Distiller platform. The protocol and the guideline applied for the Extensive Literature Search and for the update of the database are described in this report. The current version of the database includes reports of hosts of X. fastidiosa published up to 20 November 2015. The current list of X. fastidiosa host plant species consists of 359 plant species (including hybrids) from 204 genera and 75 different botanical families. Compared to the previous database, 44 new species and 2 new hybrids, 15 new genera and 5 new families were found. The majority of the additional species (70%) were reported in Apulia, Corsica and southern France.

International trade in live plant materials has increased worldwide over the last four decades. This has led to a dramatic increase in the introduction, establishment and spread of non‐native plant pathogens. Regulatory authorities need advice on measures that may mitigate these adverse consequences of trade. Risk models may be used to underpin such advice. In this review, we give a systematic overview of the data needed for a quantitative risk model for Phomopsis vaccinii, which causes stem and fruit infections on Vaccinium species, and sometimes death, potentially also on native wild Vaccinium species in the EU. P. vaccinii is a quarantine organism worldwide, except for North America, where it is endemic. Despite extensive knowledge of the aetiology of the diseases caused by this pathogen and its taxonomy, quantitative data on transportation and detection of infected plants for planting and berries are scarce, and quantitative assessment of the future introduction, establishment and spread of P. vaccinii is difficult. Estimation of the potential impact of this pathogen in production fields and wild Vaccinium stands is even more difficult. P. vaccinii is not unique in this respect, and this review indicates the need for more and better quantitative data for assessment of the risks posed by newly introduced plant pathogens in areas where they are not endemic.

Beneficial soil microbes have long been recognized for their ability to improve plant growth, to antagonize pathogens and to prime plants against biotic stressors. Nevertheless, their ability to enhance plant resistance against arthropod pests remains largely unexplored, especially in crop plants such as pepper. Herein, we assessed the effects of several fungal and bacterial species/strains applied in the soil on the performance of key pests of pepper plants. Specifically, we recorded the impact of pepper inoculation with commercial strains of beneficial bacteria (Bacillus amyloliquefaciens and Pseudomonas spp.) as well as fungi (Trichoderma spp. and Cordyceps fumosorosea) on the population growth of the green peach aphid, Myzus persicae, and the two-spotted spider mite, Tetranychus urticae. Furthermore, we recorded the effects of microbial inoculation on plant growth parameters, such as stem and root weight. We found that both pests can be negatively affected by microbial inoculation: spider mites laid up to 40% fewer eggs, and the number of aphids were up to 50% less on pepper-inoculated plants, depending on the microbe. We also recorded a variation among the tested microbes in their impact on herbivore performance, but no significant effects were found on plant biomass. Our results add to the growing literature that beneficial soil microbes may be capable of exerting biocontrol capabilities against aboveground herbivorous pests possibly, among other means, via the elicitation of plant defense responses.

As requested by the European Commission, the EFSA Panel on Plant Health (PLH) Panel assessed the risk of Diaporthe vaccinii in the EU, focusing on entry, establishment, spread and impacts on cultivated and wild Vaccinium species, the principal hosts being American and European cranberry and blueberry. Several outbreaks occurred in the EU since 1956, but most were eradicated except in Latvia. The Panel considered entry via fruits and plants for planting. The risk of establishment from discarded infected berries is much lower than from infected plants for planting, of which, potted plants and cuttings pose the greatest risk, while plug plants, derived from tissue culture and grown in pest free structures, pose a low risk. Nine per cent of the EU is highly suitable for establishment of the pathogen, mostly in the SE and NE. Following establishment, the pathogen could spread naturally over short range, and by human assistance over long range. Calculations with an integrated model for entry, establishment and spread, indicate that with current regulations, over a period of 5 years, a few hundred cultivated Vaccinium plants and several thousand Vaccinium plants in natural ecosystems would contract the disease. The associated loss of commercial production is small, less than one tonne of berries per year. On natural vegetation, the median impact after 5 years was estimated to be negligible affecting a negligible proportion of the natural Vaccinium population (2 9 10 À8 ). However, the uncertainty of this estimate was high, due to uncertainty about the rate of spread; in a worst-case scenario (99th percentile), almost 1% of plants in natural areas would become infected. Complete deregulation (scenario A1) was predicted to increase the impact substantially, especially in natural areas, while additional measures (scenario A2) would effectively eliminate the entry of infected plants for planting, further reducing the impacts below the current situation.

Following a request from the European Commission (EC), the European Food Safety Authority (EFSA) initiated a procedure for the evaluation of data supporting the necessity of the application of insecticide active substances to control a serious danger to plant health within the context of Article 4(7) of Regulation (EC) No 1107/2009. EFSA established an ad hoc working group (WG) who proposed a methodology for conducting this type of evaluation. The draft protocol was circulated among European Union Member States (MS) for commenting. The aim of this protocol is to enable a consistent and transparent evaluation of submissions made by applicants in accordance with the derogation detailed in Article 4(7) of Regulation (EU) No 1107/2009 to confirm the lack of other available means capable of controlling an identified serious danger to plant health. All the evaluations are made for each specific crop/pest combination separately for which a derogation is requested. Usually, derogation for the use of an insecticide active substance is not scientifically supported if an alternative control programme not requiring the application of an insecticide can manage the specific crop/pest combination under consideration, or if another active substance with the same mode of action (IRAC) as the active substance under consideration is available. If these conditions are not verified, the process moves to the evaluation of: 1) the risk of resistance associated to the different mode of action of all active substances that are authorised in the MS; 2) the risk of resistance associated to the different pests; 3) the availability of non-insecticide alternatives.

Intensive agricultural management practices (i.e., the burning of pruning residues, the absence of organic amendments) lead to a reduction in organic matter and nutrients in the soil resulting in agroecosystem vulnerability. Implementing a cover crop would provide soil organic matter while increasing nutrition levels in the soil. A mixture of cover crop trial in sandy loam soils under Mediterranean climatic conditions was conducted in a rainfed olive grove in Western Crete. In this study, the dry biomass, macro- and micronutrition, and carbon status of the seeded cover crops (legume and grass) were compared to natural plants in an olive grove. Seeded cover crops were conducted in two sustainable management systems (cover crops solely, and a combination of compost, pruning residues, and cover crops); natural plants were in a conventional system involving soil tillage. In combination with conservation tillage practices, the addition of carbon inputs may improve soil fertility. Results indicate that the dry biomass production and C content of cover crops under sustainable management systems was significantly higher than that of the control. The higher dry biomass production and C content found in cover crops compared to the natural vegetation indicates not only that this type of management provides enhanced carbon storage, but can also potentially lead to a future increase in soil organic matter through decomposition. Higher dry biomass is important in the context of carbon sequestration, and cover crops facilitated carbon storage in this study. In addition, this study suggests that sustainable agricultural management practices would provide significant benefits in terms of nutrient retention and CO2 fixation, thus improving ecosystems in Mediterranean countries.

Nymphal development, mortality and adult longevity of the plant bug Closterotomus trivialis were studied on two of its major crops (Olea europaea L. cv. 'Koroneiki' and Citrus sinensis L. cv. 'Washington Navel') and four non-crop host plants (Mercurialis annua L., Urtica urens L., Parietaria diffusa M. et K. and Sinapis alba L.) under laboratory conditions (15, 20, 24 and 27 °C ± 0.5%; 60 ± 5% RH; 16L:8D h photoperiod). Results demonstrated that C. trivialis can successfully complete its development on all tested host plants and temperatures, except for U. urens at 15 and 20 οC. Mortality rates were generally higher on U. urens, P. diffusa and olive than on S. alba, M. annua and sweet orange. Both temperature and host plant significantly affected the nymphal development of C. trivialis. Specifically, host plant affected the development of nymphs at lower and higher temperatures (15, 20, 27 °C) but not at the optimum (24 °C) for its development temperature. Adults of C. trivialis lived longer on sweet orange, M. annua and S. alba in most tested temperatures compared to U. urens, P. diffusa and olives. Overall, these results suggest a better suitability of M. annua, S. alba and sweet orange compared to U. urens, P. diffusa and olive which were proven to be less suitable host plants, covering partially the nutritional needs of C. trivialis. The estimated lower temperature developmental threshold based on the linear model for C. trivialis was found to be lowest on M. annua (3.30 °C) and highest on P. diffusa (10.7 °C). Τhe assessment of the nymphal development in various host plants and temperatures is particularly important for understanding the biology of C. trivialis and provides useful information to optimize its management strategy under integrated pest management system.