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1.
Flight patterns of migrant alate Russian wheat aphids (=RWA),Diuraphis noxia (Kurdj.) during its expansion from the south-east to Central Europe were determined. Samples were taken by Rothamsted-type suction air traps in Hungary (one location, 1990–1997) and in the Czech Republic (5 locations, 1994–1998). The results document a progressive expansion of RWA, and population variation in the individual years and periods of the season. A comparison of the evidence on RWA in the individual years since its detection in Hungary and in the Czech Republic supports the presumption on the occurrence of an expansion route from the south-east (Turkey) to Central Europe. This expansion is classified as an adventive route of the over-all expansion that has covered the whole West-Mediterranean (South Europe, North Africa).  相似文献   

2.
A supplementary research on Russian wheat aphid (= RVA), Diuraphis noxia (Kurdj.) between 1998-99 documented the pest distribution all over the Czech republic already. RVA abundance was proved to be significantly area-dependent within the state. The banker areas are in southern Moravia (district Znojmo, the frontier area near Austria) up to central Moravia. The determined RWA distribution area is much broader than presumed on grounds of climatic characteristics.The abundance of RVA generally decreases from the SE to the NW and N direction, as well as with the increasing altitude within the area.The highest altitude a.s.l. of RWA occurrence in the crop was 762 in. The re-classified main expansion route was determined to follow two directions (sourcing from Hungary and Austria) to southern-central-northem Moravia, and to southern Bohemia and further on to the central Bohemian lowland. The field information indicated the development of preference of RWA for barley.  相似文献   

3.
Summary The Russian wheat aphid (=RWA), Diuraphis noxia (Kurdj.) is an exotic expansive aphid on the small grains determined in the Czech republic since 1993 (1995). Determination of RWA flight patterns by suction air traps (= SATs) between 1994-1998 indicated some banker, less important, or indicated RWA distribution areas. A comparison of the RWA monitoring by SATs and by crop samples in areas more or less distant from individual SAT locations manifested a high silmilarity of RWA evidence in its overall distribution and area-influenced population numbers. Owing to geographic area-dependent features of its life-cycle (holocycly) and host plant preferences, RWA seems to be most injurious to spring barley. In spite of the role of SATs in aphid forecasting, RWA samples are recommended to be taken also from the crops at the early ripening stage as the respective SAT evidence reflects only the emigration of the alate aphids originating from the decreasing populations. In general, RWA detection by SATs was either simultaneously or successively found to reflect the RWA presence in the more or less distant crops. The 30km perimeter of a SAT is agreed to be representative for mon-toring RWA populations in a sampled area.  相似文献   

4.
The Russian wheat aphid,Diuraphis noxia (Mordw.) has been detected in southern Moravia, the Czech Republic in June, 1995. Its location is related to its incidence in central Hungary. The further predicted area of distribution covers the grain-maize growing districts of southern Moravia (Czeck Republic), neigh-bouring parts of Austria, southern and south-eastern parts of the Slovak Republic. The aphid is classified as a species expanding to the north from its mediaterranean area of distribution, apart of extensive areas (North to South Americas, S. Africa, expected in Australia) which it has covered thorugh accidental introductions and further spread over the world.  相似文献   

5.
An analysis of the Russian wheat aphid (RWA) (Diuraphis noxia Kurdj.), overpopulated due to extraordinary weather conditions (2000) in the Czech Republic, enabled the identification of several within-field situations ouside of the routine approach. This group, classified as within-field refugium, includes variation due to field relief, some injuries caused by the use of machinery, the unharvested field margins and, last but not least, the volunteer plants. Differences between the RWA populations in these situations and the normal grove are presented and recommended to be taken into consideration in the research on RWA population dynamics and movement.  相似文献   

6.
Two hot and dry weather periods during mid-spring and early summer caused severe drought-stress to barley groves in many districts of the Czech Republic in 2000. Although not generally taken into consideration as an injury-increasing factor, the Russian wheat aphid (=?RWA), Diuraphis noxia (Kurdj.), was discovered to contribute significantly to injury in the ripening stage of spring barley as well as to the substantial decrease of yield (up to 30?–?40?% of the calculated mean, in some districts). RWA increased considerably not only in the lowland banker areas but also in the higher altitudes, values in the latter case then manifesting those found in the lowland banker areas in the previous years.  相似文献   

7.
Cool and wet weather in some periods of the season generally supressed the RWA (Diuraphis noxia Kurdj.) populations in the Czech republic in 2001. However, some sites manifested population levels ranging out of the population mean stated per area, and these sites were also apparently responsible for respective peaks of alate aphids sampled by suction traps. An analysis of these sites determined them to be attributed to some poor quality barley fields in a warmer area of the state. RWA is known to vary in all-over populations in different years, and the year 2001 illustrated its capability of its surviving even unfavourable periods and seasons, remaining well-established in the area.  相似文献   

8.
Agroforestry in the Czech Republic has vanished both from the landscape and public conscience. That raises questions about its history and fate; there are examples of this land use type from all neighbouring countries. The article looks at the record of such systems in a historical land tax survey, the Franciscan cadastre made in the Czech Republic in the mid nineteenth century. With this source, patterns of preindustrial-era subsistence systems were analysed in a considerable part of what is now the Czech Republic. Any correlation among occurrences of various land uses (including agroforestry cultures) and influences of chosen natural and cultural factors was statistically tested and further visualised by multivariate analysis. The main existing agroforestry types and their historical distribution were investigated. The results have shown that cropland with fruit trees, and meadows, and pastures with either fruit trees or wood use, were a common part of Czech countryside in the mid-nineteenth century. Some agroforestry plots were found in the 1689 total studied cadastral areas. The types of agroforestry and the overall subsistence patterns were attuned to elevation, soil fertility, population density, and the dominant language group of the inhabitants. Cropland and pastures with fruit trees were associated with more fertile inland lowlands with sound infrastructure and prevalently Czech inhabitants (so-called ‘old settlement’ areas), wood meadows and pastures with cadastral units located in border regions at higher elevations characterised by lower soil fertility, a greater ratio of coniferous forests and predominantly inhabited by Czech Germans. Traditional agroforestry, as is discussed, however, did not survive the industrialisation of agriculture.  相似文献   

9.
Nine bumble-bee (Bombus)-species (listed) were determined to visit flowers of an exotic invasive species,Impatiens glandulifera Royle in the wetland biocorridors in the Czech Republic. None of the species was found specific to the target plant and the dominant part of the guild represented common eurytopic species.I. glandulifera was classified as an important source of nectar and pollen, and the significance of this source increased with the decreasing season as the bloom period lasted much longer than that of most of the native plant species. Despite its invasive effects on the native plant communities in wetlands,I. glandulifera contributed to the conservation of common bumble-bee species, as well as to an over-all positive role of wetlands in the cultivated landscape.  相似文献   

10.
While bats are important reservoirs and vectors of pathogenic agents with zoonotic potential, their skin‐associated microbial community could harbour organisms relevant to bat health as well as those associated with bat habitats in general. A total of 140 skin swabs collected from bats in the Czech Republic were cultured for bacteria from 2012 to 2013. A phytopathogen, isolated from a lesser horseshoe bat (Rhinolophus hipposideros), was identified as Lonsdalea quercina by MALDI‐TOF (matrix‐assisted laser desorption–ionization time‐of‐flight mass spectrometry) and characterized as Lonsdalea quercina subsp. britannica using phylogenetic analysis based on a 16S rRNA and two housekeeping (infB and atpD) genes. Lonsdalea quercina subsp. britannica is a gram‐negative facultative anaerobic bacterium reported to cause bark canker and drippy nut disease in oaks. Our finding provides evidence of Lonsdalea quercina in the Czech Republic (Moravian Karst). As the lesser horseshoe bat is a sedentary species, it may bio‐indicate the presence of the phytopathogenic bacterium in the broadleaved forests of the habitat of pathogen recovery. We therefore suggest active surveillance of the area of the Moravian Karst for signs of oak disease and/or decline.  相似文献   

11.
The distribution of the double spined spruce engraver beetle Ips duplicatus ranges from Scandinavia and northeastern Europe to northern Asia. In Europe, I. duplicatus usually is associated with I. typographus on Picea abies, and due to morphological similarities and similar gallery constructions the damage and significance of I. duplicatus are often not recognised and thus underestimated. I. duplicatus has been recently reported from the southern part of Poland, the Czech Republic, Slovakia, northern parts of Austria and Germany; records are missing from many other central European countries (e.g., Hungary). The species became an important pest in some parts of central Europe, and continuous outbreaks of this bark beetle have been reported in Inner Mongolia, China, since the 1950s. The aim of this study was to compare I. duplicatus populations from Europe and Asia by genetic means using the analysis of the mitochondrial DNA. Individuals of I. duplicatus populations from China, Poland, the Czech Republic and Slovakia were collected, and 520 bp fragments of the cytochrome oxidase I (COI) gene were analysed. Four haplotypes were detected and a sequence divergence of 0.8% was found between the populations from China and Europe. These differences associate with behavioural differences in the pheromone bouquet and behavioural response of the two groups. Within Europe three haplotypes were found, but due to the small sample size no significant geographical distribution was demonstrated.  相似文献   

12.
An overview of the genus Bursaphelenchus in the Czech Republic is presented, based on a recent survey for monitoring the presence of the pinewood nematode, Bursaphelenchus xylophilus, as well as on previous reports of this genus in the country. In addition, we provide a morphological and molecular characterization of four Bursaphelenchus species (B. eremus, B. pinophilus, B. vallesianus and B. borealis) found during the monitoring programme for forest pests, conducted during 2006–2010, within the Moravian and Bohemian regions. Nematodes were extracted from over 1917 insects and 1493 wood samples collected from deciduous and coniferous trees exhibiting wilting and declining symptoms. Bursaphelenchus species were found only in 0.73% of insects and 0.47% of the total number of wood samples. Bursaphelenchus borealis and B. pinophilus dauer juveniles were found associated with the insect vectors Dryocetes autographus and Pityogenes bidentatus, respectively. While a total of seven Bursaphelenchus species are now reported from the Czech Republic, the status of B. xylophilus remains as absent.  相似文献   

13.
The Czech Republic is passing the third outbreakperiod ofIps typographus since 1880. The first and second outbreaks (1870–1876 and 1945–1954) were a consequence of falling of masses of trees caused by storm. The data ofIps duplicatus during the first outbreak mentioned in later papers are a mistake, reality it has beenIps amitinus.The third outbreak from 1980 until now has not one but several from man dependent and not dependent causes. There are: Falling of trees, by repeating windstorms damage of trees by pollutions of SO2 and their pollutants, the increasing temperatures during the last period of 30 years and the development of higher numbers of generations of the beetle. The successes in using pheromones in control ofIps typographus were overestimated. Also the changes in the ownership of forest stands were of importance. Ips duplicatus occured in North Moravia having been migrated across Northpoland to the east Czech Republic.In the Nationalpark of umava (on the other side to the Nationalpark of Bavaria) in some reservations no measures againstIps typographus as in Bavaria were made. Here new control measures must be taken against this pest.  相似文献   

14.
Between 2008 and 2010, horse chestnut (Aesculus hippocastanum) trees growing at 216 locations in the Czech Republic were surveyed for bleeding canker disease. Typical symptoms of bleeding canker were found at 16 locations, and samples were collected from five of these locations. The bacterium Pseudomonas syringae was isolated from five locations, and Pseudomonas syringae pathovar aesculi, which is the causal agent of bleeding canker disease, was isolated at one location. This is the first report of P. syringae pv. aesculi in the Czech Republic.  相似文献   

15.
The population structure of Hymenoscyphus fraxineus, the causal agent of ash dieback, was assessed at four closely located sites in the Czech Republic. To analyse the genetic variation, one Swiss and one Norwegian population with known population structures were selected as reference points. The analysis was performed using 16 previously published and five newly developed microsatellite markers. The quality of the new markers was assessed by sequencing the flanking region, identifying the type of the mutation and analysing the inheritance and linkage between all pairs of loci. In addition, markers were tested on 45 Japanese strains to confirm their usability on native H. fraxineus populations in Asia. One of the new markers was monomorphic in all European populations and one marker exhibited a high percentage of null alleles in the Japanese samples. Twenty markers in the four Czech populations showed lower average gene diversity than in the other two European populations. One Czech population significantly differed from all the others, with a pairwise GST of approximately 0.2, the lowest allelic richness and very low average gene diversity, likely resulting from a founder effect. The amount of genetic differentiation between the four neighbouring Czech populations exceeds the expected value from previous Europe‐wide population studies and suggests that local population dynamics can affect the population structure of H. fraxineus.  相似文献   

16.
Red wood ants (Formica rufa group, RWAs) are common insects in boreal forests in Fennoscandia, and they build large, long-lived mounds as their nests. RWA mounds are enriched with carbon and nutrients, but little information is available about how they affect root distribution and the nutrient uptake of trees. In this study, we investigated the biomass, biomass density, nutrient concentrations, and amounts of fine (<2 mm) and coarse (>2 mm) roots in RWA mounds, and compared them with those of surrounding forest soil in mixed coniferous stands of different age classes in Finland. Neither fine nor coarse root biomasses differed significantly between the aboveground parts of the mounds and the organic layer of the soil. Root biomass density was lower in mounds than in the organic layer. However, fine root biomass and biomass density were higher in the belowground parts of mounds than in the surrounding mineral soil. Macroelement (N, Ca, K, P, S, Mg) and Zn and Cu concentrations in roots in the mounds were significantly higher than those in the organic layer. Root biomass and biomass density did not differ between stands of different age classes. The results of this study indicate that RWA mounds increase heterogeneity in root distribution in forest ecosystems, and also increase the availability of nutrients for plants that extend their roots inside RWA mounds.  相似文献   

17.
The method of standardized baited pitfall, traps for monitoring population ofHylobius abietis (L.) was experimentally included into the routine planting and control schedule (model area) in the Czech Republic. It is recommended to determine characteristics of the area on the basis of long-term monitoring. A short-term prognosis per site must be drawn from monitoring done from the earliest beginning of the season. However, it seems advisable to treat all the individual seedlings immediately after theyhave been planted in the area where the over-all characteristics (ascertained by monitoring) indicate generally high population levels. To base a decision for treatment on the percentage of seedlings attacked (feeding scars) per site is considered unadvisable in comparison with data obtained bymonitoring using baited pitfall traps. Insecticides for the treatment of newly planted seedlings need to be applied to two-thirds of the trunk of a seedling (including the root collar), their action should be fast enough to paralyse (kill) the weevils before they reach xylem by feeding and, furthermore, the residues should be effective up to the end of the season.With one figure and 3 tables  相似文献   

18.
Fifteen eriophyid mite species are the most abundant species in the Czech Republic from which four, viz.Eriophyes fraxinivorus onFraxinus excelsior, E. platanoideus onAcer platanoides, Phytoptus pyri onPyrus communis andStenacis triradiatus on various species ofSalix injure their host plants and are evaluated as pests. The weight of the leaves attacked by eriophyid mites increase with increasing number of galls pro leaf but the surface of attacked leaves decrease with increasing attack. Harmfulness of eriophyid mites manifests by reducing of assimilation processes, retardation of growth, precocious drying and fall-off of attacked leaves. Heavily attacked young shrubs and trees may dry and decease.With one figure and 2 tables  相似文献   

19.
The first capture of the synanthropic cockroachPeriplaneta brunnea (Burm.) in the Czech Republic (Prague airport) is recorded.  相似文献   

20.
云杉属谱系地理学主要是研究云杉属种群遗传结构的历史动态规律,以及气候振荡和地质变迁对种群分布范围、种群间基因渐渗及遗传分化的影响。文中综述了国内外云杉属谱系地理学的研究进展,结论如下:我国西南山区和青藏高原（QTP）地区云杉属树种谱系地理学研究,验证了上新世QTP上升和第四纪冰期气候振荡对该物种进化起到推动作用,该物种在这2个时期快速分化;在云杉属争议种的研究中,通过对云杉属复合种群的群体结构展开研究,揭示了种群间的基因渐渗常存在于有较低基因流的基因组,方向通常是由本土树种向入侵树种渗透;某些种群之间的基因渐渗可有助于在一些基因位点上增加这些种群和其他种群之间的分化,导致生殖隔离的产生;云杉属天然杂种多被发现在种群的对称分布区边缘、或者其重叠分布区,杂种经过异地扩张又形成了新种,验证了云杉属网状进化的历史,并证明了生境特征决定杂交优势种的分布边界。  相似文献   

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