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1.
A preliminary analysis demonstrated that the powdery mildew fungus infecting Syringa spp. (lilacs) in different parts of the world is divided into two groups (S-type and K-type) based on the nucleotide sequences of the rDNA ITS regions. In spite of the marked genetic differences (only c . 94% similarity between ITS types), fungi belonging to these two ITS groups are difficult to distinguish based on morphological characteristics. To determine their geographical distribution, ITS haplotypes were determined for a total of 139 powdery mildew specimens collected in Asia, Europe and North and South America between 1977 and 2005. Curiously, until 1990, only the S-type was found in Europe, whilst the K-type prevailed in East Asia. The first European specimen belonging to the K-type was collected in Ukraine in 1991. Other European K-type samples were collected in Lithuania and Switzerland in 2000, and in other countries after 2002. The incidence of the S-type decreased rapidly in Europe after the 1990s. This result strongly suggests that the K-type was introduced to Europe from East Asia in the 1990s and expanded from Eastern Europe westward, replacing the S-type present on the European lilacs. The K-type produces abundant chasmothecia (sexual fruiting bodies), whereas chasmothecia on the S-type are rare in Europe and East Asia. It is likely that the recent abundant production of chasmothecia on Syringa spp. in Central Europe is explained by the migration of the K-type to Europe.  相似文献   

2.
A survey of the ecological adaptations of the bank vole, Clethrionomys glareolus (Schreber), indicates that this species is a potential pest, particularly to forest tree seeds and bark. Observations from most parts of Europe show clear cases of damage to seeds, young shoots and buds and bark of young trees above the snow level. Worst losses appear in central and eastern Europe. The bank vole may also attack a few year old seedlings (either bark or complete consumption). Widespread seedling attacks, which are economically very important in some countries, have, however, not been definitely proven for this species. In northern Europe, the bank vole may also cause damage to hay in barns. Bank vole populations show greatest fluctuations in eastern and northern Europe. The cycle length is variable. Damage (except, possibly, seed consumption) appears mainly during or just after the appearance of peak populations. Baits with zinc phosphide seem to be the most efficient control method. A number of other preparations have been tried more or less successfully. In summary, knowledge of the economic importance of the bank vole is very restricted. Specific studies are suggested for improving such an evaluation.  相似文献   

3.
N. Ogris  D. Jurc  M. Jurc 《EPPO Bulletin》2006,36(3):475-485
Eutypella canker of maple, caused by the pathogen Eutypella parasitica, has recently been reported for the first time in Europe. A rule‐based model of Eutypella parasitica spread risk in Europe is presented. This model incorporates the effects of spatial and temporal variability of multiple variables on pathogen spread and establishment. Model predictions are based on current knowledge of host susceptibility, pathogen reproduction and pathogen transmission, with particular regard to the host species’ distribution and climate suitability. Maps of host species’ distributions and monthly weather conditions were spatially analyzed in a Geographic Information System using the magnitude and direction of each variable's effect on disease spread. Spread risk predictions were computed for each month and averaged to generate a cumulative risk map. The model was calibrated using data on the natural distribution of Eutypella canker in North America. Extensive areas covering the natural distribution of maples in Europe are at considerable risk from the Eutypella parasitica infection. The most endangered regions are broad areas of the Balkans, the Apennines, France, Central and Eastern Europe and the Caucasus.  相似文献   

4.
Phytophthora infestans (Mont.) de Bary, the causal agent of potato late blight, was first discovered in Europe in 1845. Until 1980, only A1 mating type isolates were known to occur in Europe. The absence of A2 mating type isolates restrained the fungus from sexual reproduction. In the early 1980s, A2 mating type isolates were discovered in Europe. Presumably, a new introduction ofP. infestans isolates originating from Mexico had taken place. In this paper, the significance of the presence of A1 and A2 mating type isolates in the Netherlands is reviewed. Now that both mating types are present, sexual reproduction can occur and its consequences for the control of potato late blight are discussed.  相似文献   

5.
The biology of late blight of potato and tomato, caused by Phytophthora infestans, changed when sexual reproduction by the pathogen became possible in many parts of the world, including Europe. In northern Europe, especially Scandinavia, there is increasing evidence that the pathogen is reproducing sexually on a regular basis, although in other regions further south or to the west it appears to reproduce primarily in a clonal manner. The presence of both mating types, the production of viable oospores, and observations of fields with soilborne sources of inoculum are consistent with sexual reproduction. Studies with different marker systems have revealed a population structure without any dominating clonal lineages in Scandinavia, and that is most easily explained by sexual reproduction. Phytophthora infestans recovered from the soil can also be linked to parental genotypes using likelihood‐based methods when codominant markers are used. A synthesis of all the available data points to a second centre of sexual reproduction in northern Europe.  相似文献   

6.
Walnut (Juglans regia L.) is traditionally present in most European countries as an ornamental tree, and in Southern Europe in particular it is grown for both fruit and wood. Since the 1980s, to supply the increasing demand for walnut timber, large areas of southern and central Europe, from France to Hungary, have been planted with black walnut (Juglans nigra L.) to provide wood for furniture production. The fungus Geosmithia morbida and its vector Pityophthorus juglandis, causing the thousand cankers disease of walnut in the USA in the last 2 decades, were recently reported in Europe (in Italy) on both walnut species. Thousand cankers disease can have a high negative impact on the landscape and economy of many agricultural and forest areas. Following a detailed pest risk analysis performed by EPPO in 2015, both organisms were included in the EPPO A2 List of pests recommended for regulation as quarantine pests. The main biological, epidemiological and monitoring aspects of thousand cankers disease and its status in Europe are reported.  相似文献   

7.
F. Roll-Hansen   《EPPO Bulletin》1973,3(3):133-137
The pathogens which present the greatest potential dangers to European and Mediterranean forest trees are mainly to be found in remote areas such as those parts of the American continent and East Asia where the climate and tree species are similar to those in Europe. In general, inspections are not sufficient to guarantee that a consignment is free from known, and especially from unknown, pathogens. Phytosanitary regulations should therefore be based on the prohibition of the importation of living plants (not seeds). The prohibition of the importation of all conifers (not seeds) from all countries outside Europe and the Mediterranean area is proposed. All European and Mediterranean countries should agree upon effective and co-ordinated phytosanitary regulations.  相似文献   

8.
The interpretation of information used to defend an assessment that T. indica, the cause of Karnal bunt of wheat, has a high risk of establishing in Europe and of causing significant yield/quality losses is questioned. Karnal bunt has only established in locations that are arid or semi-arid with hot summers and cool/mild winters. There is very strong circumstantial evidence that substantial amounts of seed contaminated with teliospores of T. indica were sown in Europe in the past without the appearance of Karnal bunt. It is unlikely that sufficient numbers of teliospores would survive long enough on the soil surface under European conditions and then synchronise germination during the period at heading when wheat is vulnerable to infection to guarantee disease expression. Karnal bunt is regarded as a minor disease everywhere it occurs. Almost two thirds of European wheat cultivars inoculated by a severe boot injection method have been categorised as either resistant or highly resistant to T. indica. Yield/quality losses would be expected to be low even if the pathogen were capable of establishing in Europe. The status of T. indica as an important quarantine pest is based on the indirect economic consequences of the appearance of the pathogen and not on the direct damage it causes to wheat crops. Arguments in this and previous reviews advocating a more reasoned and comprehensive assessment of the threat to Europe, North America and other locations from T. indica need to be taken into consideration in any new pest risk analyses. David Jones is a retired employee of the Central Science Laboratory (CSL). Statements and opinions expressed in this paper are those of the author and are not the views of CSL.  相似文献   

9.
EU agriculture is currently in transition from conventional crop protection to integrated pest management (IPM). Because biocontrol is a key component of IPM, many European countries recently have intensified their national efforts on biocontrol research and innovation (R&I), although such initiatives are often fragmented. The operational outputs of national efforts would benefit from closer collaboration among stakeholders via transnationally coordinated approaches, as most economically important pests are similar across Europe. This paper proposes a common European framework on biocontrol R&I. It identifies generic R&I bottlenecks and needs as well as priorities for three crop types (arable, vegetable and perennial crops). The existing gap between the market offers of biocontrol solutions and the demand of growers, the lengthy and expensive registration process for biocontrol solutions and their varying effectiveness due to variable climatic conditions and site‐specific factors across Europe are key obstacles hindering the development and adoption of biocontrol solutions in Europe. Considering arable, vegetable and perennial crops, a dozen common target pests are identified for each type of crop and ranked by order of importance at European level. Such a ranked list indicates numerous topics on which future joint transnational efforts would be justified. © 2016 Society of Chemical Industry  相似文献   

10.
The field vole, Microtus agrestis (L.), is a major pest in horticulture and forestry in all Scandinavian countries, and an important forestry pest in certain regions in central Europe. The most common type of damage is girdling trunks of cultivated trees, usually under the snow cover. In horticulture, the apple tree is the commonest subject of injury, while, in forestry, several deciduous and conifer species are attacked. In Finland and Norway, the garden industry has suffered most, while, in Sweden, the problems are predominantly in forestry. In central Europe, M. agrestis is a forestry pest only. Summation of all losses due to the field vole since World War II amounted to somewhere between 50 and 100 million US Populations of M. agrestis normally undergo cyclic fluctuations. However, comparison of the periodicity of outbreaks in different areas reveals variations, 3 to 4-year intervals dominating in the Scandinavian countries, while the interval in central Europe is generally somewhat shorter. No overall synchrony exists over the geographical range of the species. Present knowledge concerning the demography and habitat dynamics of M. agrestis is briefly reviewed. Current possibilities for preventing damage by M. agrestis are much dependent on the individual value of the potential subjects of injury. High value stands, like apple gardens or seed orchards of forest trees, can be protected by means of mechanical guards. However, current means of combating damage in forest plantations are badly limited. Surface spraying with toxaphene and poison baits is practised in central Europe, while, in the Scandinavian countries (except Denmark), no chemical means are used today. Development of new compounds to be used as surface sprays, or specific baits for M. agrestis, is urgently needed. Research on bio-control methods should also be intensified.  相似文献   

11.
Bark‐ and wood‐boring beetles in the genus Agrilus (Coleoptera: Buprestidae) can survive wood‐chipping, and Agrilus planipennis has established in North America and European Russia with devastating impacts on forest ecosystems. The work presented in this paper combined import statistics of deciduous wood chips, Maximum entropy modelling (MaxEnt) of climatic similarities, and the distribution of potential tree hosts to predict the likelihood of four selected North American Agrilus species to become introduced and established in Europe. In agreement with the EU's energy‐policy target of increased use of wood chips, there was a linear or exponential increase in European imports of deciduous wood chips during the past 10 years from countries harbouring potentially harmful Agrilus species. MaxEnt showed high environmental suitability in Europe for the four selected Agrilus species, particularly in Eastern Europe and European Russia for A. anxius, A. bilineatus and A. planipennis and in southern Europe for A. politus. Documented susceptible host trees are widely distributed in the predicted areas of Agrilus distribution in Europe, and these areas receive large quantities of deciduous wood chips from countries where these and other Agrilus species are present. Thus, it was concluded that the fundamental conditions for introduction and establishment of Agrilus species in Europe are in place.  相似文献   

12.
Monilinia fructicola is a quarantine fungal pathogen in Europe, but many major stone fruit growing countries in Europe have reported its presence recently. In Switzerland, the fungus was first found in a single apricot orchard in 2008. This study confirms the presence of M. fructicola in nine out of 22 commercial orchards in Canton Valais, Switzerland. Five simple sequence repeat markers (SSRs) were developed for M. fructicola and samples from Switzerland, Spain, Italy, France and the United States were analysed and compared in order to assess the genetic diversity of the pathogen, identify the origin of the disease, and verify if the fungus reproduces sexually in Europe. In the 119 European samples analysed, 12 different haplotypes were found, indicating a relatively high genetic diversity of the pathogen considering that the first report in Europe was 10 years ago. Three haplotypes found in Europe were identical to those found in the American samples (two from the east coast and one from the west coast). Population structure analysis suggests that the European population is derived from at least two ‘invasion’ events probably originating from the US (one from the east coast, the other from the west coast). Preliminary evidence of sexual reproduction of M. fructicola in Europe is reported.  相似文献   

13.
The carrot fly (Psila rosae) is a major pest of umbelliferous crops, particularly in carrot production. This pest is present in temperate regions of Northern and Western Europe and also in the warm and dry climate of Central and Southern Europe. Currently, control strategies are limited and there may be a bottleneck of pest control solutions in the future. In practice, growers in the Netherlands mainly rely on a commercial, supervised control system which monitors the carrot fly population pressure. Possibilities to control the carrot fly after exceeding an economical threshold are reduced due to a lack of efficient chemical insecticides. Another option is the use of seed treatment to protect the carrots against the larvae developed from the first flight of the carrot flies for 12–14 weeks after sowing. The state of the art of the carrot fly pest and control possibilities are hereby discussed. Bottlenecks in control of carrot flies are highlighted and described.  相似文献   

14.
《EPPO Bulletin》1998,28(1-2):27-38
The main technical theme of the 2nd EPPO Worksh op for Heads of Plant Quarantine Services of central and eastern European countries was the risks presented to the forests of the EPPO region by quarantine pests. Measures currently recommended by EPPO concentrate on A1 quarantine pests, not present in the region. Nevertheless, measures applied by many European countries, and in particular by the EU, target non-European forest pests. This presents a particular problem for Russia, since its territory lies partly in Europe and partly in northern Asia and the export of forest products is very important for its economy. Against the background of the new global developments in plant protection (revision of the IPPC, SPS agreement), the Workshop opened the question whether there are forest pests in northern Asia which present a risk to Europe (and vice versa). Recognizing that one of the main non-European pests targeted by the regulations of European countries is Bursaphelenchus xylophilus , the Workshop took note of the fact that this pest does not occur in Russia. Certain known or potential vectors of B. xylophilus in the genus Monochamus do occur in Russia, but also occur widely throughout the palaearctic region. The forest fauna of northern Russia remains fairly homogeneous from Europe to the River Yenisei, and then becomes progressively more different. Nevertheless, specific pests from this eastern region presenting a risk to Europe remain to be identified and subjected to pest risk analysis.  相似文献   

15.
H. K. Berger 《EPPO Bulletin》2001,31(3):411-414
The western corn rootworm Diabrotica virgifera virgifera is one of the most dangerous pests in maize in the USA. For many years, US growers have had to control this pest in maize fields by soil treatment or spraying. Ten years ago, this pest was also 'imported' into Europe. It was the job of the plant protection advisers and officials to inform endangered countries about the appearance of this pest, to develop control strategies for Europe and to establish research programmes to prevent further spread. This paper presents the history of this pest in Europe, its biology, the situation in 2001 and corn rootworm management scenarios for the future.  相似文献   

16.
BACKGROUND: Pollen beetle (Meligethes spp.) is a major pest of European oilseed rape crops. Its resistance to pyrethroid insecticides has been recorded in samples of beetles collected in Europe since at least 1999, and problems with the control of the beetle in the field have been widely reported. In 2007, a Pollen Beetle Working Group was formed through the Insecticide Resistance Action Committee (IRAC) in order to coordinate efforts for surveying pyrethroid resistance development. RESULTS: The results of the first 3 years of the pollen beetle pyrethroid susceptibility survey using a laboratory test are presented in this paper. Resistant beetle samples were collected from 20 of the 21 countries surveyed, with a general trend of increasing frequency and spread of resistant samples in European oilseed‐rape‐growing regions. CONCLUSION: Pyrethroid‐resistant beetles dominate in Western and Central Europe and are becoming established in the North and East, the main oilseed‐rape‐growing areas of Europe. The development and spread of pyrethroid‐resistant pollen beetles highlights the need for effective management strategies for oilseed rape insect pests. Copyright © 2011 Society of Chemical Industry  相似文献   

17.
Journal of Plant Diseases and Protection - The gypsy moth, Lymantria dispar, is one of the most important pests of deciduous trees in Europe, occurring in all environmental zones of Europe except...  相似文献   

18.
Phytophthora infestans is the causal organism of potato late blight, the most important disease in potato, the second most important arable crop in Europe. The P. infestans population in Europe is well known for its sudden changes in composition. Currently it is composed of a wide variety of genotypes, some of which are dominant clonal lines while others are rare or even unique to a year or location. Fungicides play a crucial role in the integrated control of late blight. Since its introduction in the Netherlands in 1992, fluazinam has been used in late blight control strategies in ware and starch potatoes. It has a broad spectrum of activity and is effective against a range of diseases including potato late blight. Fluazinam interrupts the pathogen cell’s energy production process by an uncoupling effect on oxidative phosphorylation. It is considered to have a low resistance risk. Until recently, reduced efficacy against fluazinam was not detected in P. infestans surveys in Europe. In this paper we present the finding of a new clonal lineage (EU_33_A2) of P. infestans in the Netherlands and the reduced efficacy of fluazinam to control one of the EU_33_A2 isolates in field experiments carried out in 2011 and 2015 under high disease pressure. The potential effects of this finding on practical late blight control strategies are discussed.  相似文献   

19.
Plum pox situation in Europe   总被引：3，自引：0，他引：3  
The EPPO Conference on plum pox organized at Bordeaux (FR) in 1993–10 included a round-table session at which scientists from research and plant protection services of EPPO Member Governments reviewed the current national status of the disease. These reports have been summarized and compared here. They show that plum pox is the most serious disease of stone fruit in Europe and that nearly all countries which produce stone fruits are affected to a greater or lesser extent. Broadly, Europe can be divided into three zones: (1) the central and eastern countries in which plum pox spread relatively early and levels are generally high; (2) the northern and western countries in which plum pox levels are very heterogeneous (sometimes fairly widespread as in Germany, sometimes very restricted as in France, sometimes absent as in Netherlands); (3) Mediterranean countries in which spread is relatively recent and there is high risk of further spread.  相似文献   

20.
Pseudoperonospora cubensis causes great losses in cucurbitaceous crops worldwide. In cool temperate climates of northern Europe or North America overwintering as active mycelium is not possible, because all hosts so far reported there are summer annuals. Oospores have not yet been found in these regions under field conditions. The only perennial member of the Cucurbitaceae found naturally in central and northern Europe is Bryonia dioica. To date this plant has not been recorded as a host for downy mildews, but our infection trials demonstrate that P. cubensis is able to infest this plant. Amplification and sequencing of the ITS rDNA confirmed the observed downy mildew disease on B. dioica as P. cubensis. From these findings, the possibility that P. cubensis may be able to overwinter on this perennial host cannot be excluded. Whether or not B. dioica plays a part in the epidemology of P. cubensis in Europe requires evaluation by further studies.  相似文献   

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