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1.
Dothistroma needle blight (DNB) has been observed in Slovakia during the last two decades. Up until 2017, Dothistroma septosporum has only been detected and molecularly confirmed to cause DNB in Slovakia. Here, we report the detection of Dothistroma pini at six localities around Slovakia, representing different plantation types. Four pine species (Pinus sylvestris, P. nigra, P. mugo and P. jeffreyi) were confirmed as hosts of D. pini in Slovakia, of which only P. mugo has been previously reported as host in Slovakia. Three gene regions (ITS, EF1 –α, and ß-tubulin) of each of the 13 isolates were sequenced and assigned as D. pini. Based on ITS sequences, the studied isolates represent the haplotypes Dp_HAP.1, Dp_HAP.2. Both mating types were detected but at different localities. Our results suggest that in addition to D. septosporum, D. pini may contribute to DNB also in Slovakia.  相似文献   

2.
Extracellular proteins were extracted from Phellinus weirii infected Douglas‐fir (Pseudotsuga menziesii var. menziesii) roots and needles to examine endochitinase activity. Chitinases have been associated with the plant's defence response against fungal attack because they hydrolyse chitin, a structural component of fungal cell walls. Protein separation using sodium dodecyl sulphate‐polyacrylamide gel electrophoresis (SDS‐PAGE) followed by Western immunoblot analysis using a polyclonal antibody specific to an endochitinase‐like protein (ECP) resulted in the detection of up to three polypeptides between 27 and 30 kDa in size. Two‐dimensional gel electrophoresis (2‐D PAGE) followed by Western immunoblot analysis revealed that the apoplastic fluid contained multiple ECP isoforms with isoelectric points (pIs) ranging from 5.3 to 5.8 and molecular masses of 27–30 kDa. Chitinase activity in needle and root tissues was measured spectrophotometrically using a colorimetric assay. A gel overlay technique using glycol chitin as a substrate for endochitinase was applied to confirm that the ECP antibody detected an enzymatically active protein. The apoplastic fluid collected from P. weirii‐infected winter Douglas‐fir needles showed anti‐freeze activity and seasonal analysis of needle tissue showed some evidence of ECP accumulation in winter months. ECP was distributed systemically throughout the tree. Increased levels of endochitinase activity in the region of P. weirii infection supports a physiological role for ECP in the plant defence response.  相似文献   

3.
Dothistroma needle blight (DNB) is a serious disease of pines (Pinus spp.), with a worldwide distribution. It is caused by the ascomycete fungi Dothistroma septosporum (teleomorph: Mycosphaerella pini) and Dothistroma pini (teleomorph unknown). Recently, DNB was found on Pinus peuce in Austria, Pinus pallasiana in Ukraine and the European part of south-western Russia, as well as on Pinus radiata and Pinus wallichiana in Bhutan. Based on DNA sequence comparisons of the internal transcribed spacer and β-tubulin gene regions, isolates from Austria and Bhutan were identified as D. septosporum, while isolates from Ukraine and south-western Russia were identified as D. pini. Additional isolates studied from Pinus mugo in Hungary confirmed the presence of D. septosporum in this country. The record of D. septosporum on exotic P. peuce in Austria represents a new host report of this needle blight pathogen in Europe. Likewise, DNB and the associated pathogen, D. septosporum are reported from Bhutan, eastern Himalayas, for the first time. In addition, D. pini was found in two European countries and on a new host, P. pallasiana. These European records represent the only reports of D. pini from outside the north-central USA. Morphological examination of selected specimens from different hosts and countries showed that D. septosporum and D. pini overlap in the length of their conidia, while the width is slightly wider in D. pini than in D. septosporum. The differences in conidial width are so small, however, that identification of the two Dothistroma species solely based on morphology is virtually impossible. The new host and country records provided here are consistent with the continuing trend of reports of the DNB pathogens from new hosts and new geographical areas during the last two decades, particularly in the northern hemisphere.  相似文献   

4.
Dothistroma Needle Blight (DNB) has been known in Slovenia since 1971, but the disease symptoms have intensified in recent years. With this study, the DNB symptoms in Slovenia are for the first time connected to both phytopathogenic Dothistroma species: D. pini and D. septosporum. Based on the ITS‐rDNA comparisons, the Slovenian isolates of D. pini group with the D. pini isolates from France, Hungary and the USA and not with the D. pini isolates from Russia and Ukraine. Both mating types MAT1 and MAT2 of D. septosporum are present in Slovenia, while for D. pini, only MAT2 was found. The current widespread occurrence of D. pini in native forest stands indicates the prolonged presence of this species in Slovenia.  相似文献   

5.
Phellinus sensu lato (s.l.) is a complex of segregate genera that act as aggressive pathogens of woody plants. Nearly all of the genera in this complex have unresolved taxonomies, including Porodaedalea, which is one of the most important trunk rot pathogens of coniferous trees throughout the northern hemisphere. In an attempt to elucidate the species within Porodaedalea, a multilocus phylogenetic analysis was performed with partial sequences from four loci (internal transcribed spacer, nuclear large subunit, tef1 and rpb2) using 41 isolates that originated from North America and Europe. For reference, we analysed the neotype isolates of Porodaedalea pini and P. chrysoloma. Our results confirmed that Porodaedalea pini s.s. and P. chrysoloma s.s. are unique phylogenetic species that do not occur in North America. We detected two discrete clades of Porodaedalea originating from the southwestern and southeastern United States. Isolates from these regions grouped with significant statistical support and represent undescribed taxa. With the exception of P. cancriformans, our analyses revealed monophyly among 28 isolates originating from the northern United States, Canada and Fennoscandia, a group we have labelled the ‘Holarctic group’. Holarctic group isolates were collected from Larix, Picea, Pinus, Pseudotsuga and Tsuga and were presumed to represent at least four morphological species (P. gilbertsonii, P. laricis, P. pini s.l. and P. piceina). Tests of gene flow and genetic differentiation detected significant differences among Holarctic group isolates by region of origin, and three subgroups were designated: (i) Atlantic‐Boreal; (ii) Interior; and (iii) Pacific. Neutrality tests using the Holarctic group demonstrated significant departures from the standard neutral model of evolution and could indicate that a diversifying selection has maintained rare phenotypes in the population, which has fostered taxonomic confusion in Porodaedalea.  相似文献   

6.
The relationship between the occurrence of sporophores of the root rot pathogen Inonotus tomentosus (Basidiomycota, Hymenochaetaceae) and disease symptoms was studied in a white spruce plantation (Picea glauca) in Canada over a period of 14 years. Numbers of sporophore clusters (three or more sporophores within 1 m of each other) were well correlated with numbers of infected living or dead trees (r = 0.64–0.86, p = 0.000–0.003). Infected trees may have sporophores around them before external symptoms of disease occur on the tree. As numbers of dead trees increased, the numbers of infected living trees remained constant, indicating increased infection within the stand. However, the number of sporophores varied considerably between the years. The diagnostic value of sporophores for tomentosus root rot is discussed.  相似文献   

7.
Dothistroma septosporum and D. pini are the causal agents of Dothistroma needle blight (DNB) of Pinus spp. in natural forests and plantations. The main aim of this study was to develop molecular diagnostic procedures to distinguish between isolates within D. septosporum, for use in biosecurity and forest health surveillance programmes. This is of particular interest for New Zealand where the population is clonal and introduction of a new isolate of the opposite mating type could have serious consequences. Areas of diversity in the dothistromin toxin gene clusters were identified in D. septosporum (51 isolates) and D. pini (6 isolates) and used as the basis of two types of diagnostic tests. PCR‐restriction fragment length polymorphism (RFLP) of part of the dothistromin polyketide synthase gene (pksA) enabled distinction between two groups of D. septosporum isolates (A and B) as well as distinguishing D. septosporum and D. pini. The intergenic region between the epoA and avfA genes allowed further resolution between some of the A group isolates in RFLP assays. These regions were analysed further to develop a rapid real‐time PCR method for diagnosis by high‐resolution melting (HRM) curve analysis. The pksA gene enabled rapid discrimination between D. septosporum and D. pini, whilst the epoA–avfA region distinguished the New Zealand isolate from most other isolates in the collection, including some isolates from DNB epidemics in Canada and Europe. Although this study is focused on differences between the New Zealand isolate and other global isolates, this type of diagnostic system could be used more generally for high‐throughput screening of D. septosporum isolates.  相似文献   

8.
Dothistroma septosporum and D. pini cause the serious pine needle disease, Dothistroma needle blight (DNB). Of these, D. septosporum has a global distribution, while D. pini is known only from the USA, Russia, Ukraine and France. During a study of D. septosporum isolates from Pinus nigra in Hungary, microsatellite markers revealed the presence of a second Dothistroma species. The aim of this study was to identify the DNB pathogens occurring in Hungary using four different molecular techniques. These included sequencing of the rDNA ITS region, a species‐specific ITS‐RFLP, mating type primers and a diagnostic microsatellite marker, Doth_A. Results showed that both D. septosporum and D. pini occur in Hungary and that both DNB pathogens were present on the same trees and in some cases, the same needles. Mating types MAT1 and MAT2 of D. septosporum were shown to be present in Hungary, but only the MAT2 of D. pini was found. In addition, examination of needles with DNB symptoms from Russia revealed the presence of D. pini on Pinus pallasiana and P. nigra as well as on a new host, Pinus mugo. The molecular markers applied in this study were sufficiently robust to identify and differentiate between the two DNB pathogens, both in culture and directly from needles. They will consequently be useful to document the geographical range and to monitor the spread of D. septosporum and D. pini in future studies.  相似文献   

9.
An epidemic wood‐decaying fungus, Inonotus rickii, originating from South America, has spread to the Mediterranean area and southern China. We report the first observation of this fungus on Acacia richii in Panzhihua, southern China. It causes serious canker and decay on urban trees in the investigated area. In addition, phylogenetic analysis showed that the fungus from Panzhihua is closely related to isolates from Europe, South America, Mianyang and Hainan of China. Moreover, it was concluded that the isolates of the species previously reported from the USA do not belong to I. rickii.  相似文献   

10.
Summary Two highly variable DNA markers were developed for Cronartium flaccidum and Peridermium pini. The markers were used to study the genetic composition of aecia of single cankers of both species. All five cankers of P. pini were homogenic and contained only one allele in both loci studied, indicating that the aecia were homozygous. The homogeneity of the cankers suggested that either genetic exchange via spermatization does not occur in autoecious P. pini populations, or that the pairing is homothallic. Two C. flaccidum cankers contained heterozygous loci. However, one canker contained genetically variable aecia indicating heterothallism, whereas the aecia of the other canker were homogenic.  相似文献   

11.
The occurrence and distribution of Dothistroma needle blight (DNB) were studied in 2014–2017 around Slovakia. A total of 84 localities, both native and planted, were investigated, and the presence of DNB was confirmed in 73 of them. In all positive locations, symptoms typical of DNB were observed and the Dothistroma species was confirmed using species‐specific primers either from fungal cultures or directly from needles. Both Dothistroma species—D. septosporum and D. pini—were identified. Both species occurred together in 29 locations, only D. septosporum in 42 and only D. pini in two locations. The host range of D. septosporum included 10 pine species and two spruce species. The host range of D. pini comprised the same number of pine hosts but only one spruce species. Five pine hosts, P. aristata, P. coulteri, P. densiflora, P. jeffreyi, P. × schwerinii, and one spruce host P. abies are new hosts species of D. pini. P. densiflora and Picea pungens have earlier been reported to be susceptible for DNB. In this study, D. septosporum was found from both tree species.  相似文献   

12.
Inonotus rickii was detected for the first time causing cankers and decay in Acer negundo and Celtis australis in Italy. In a boxelder boulevard, declining trees showed sparse foliage, exudations and cracks in the bark; in some cases, chlamydospore masses were present. Five isolates were collected and compared by growth tests in vitro and electrophoretic analyses; three isolates from the same boulevard showed very similar physiological characters. The increasing importance of the pathogen in urban areas is underlined and discussed.  相似文献   

13.
Axenic cultures of Peridermium pini obtained from aeciospores on diseased Pinus sylvestris in north-east Scotland typically had an ill-defined margin and a fluffy surface, while those from East Anglia had a well-defined margin and appeared mucilaginous. The difference in colony ap-pearance is consistent with other evidence for a distinction between the forms of P. pini in the two parts of the United Kingdom. After a few months, thin sectors, comprising a rapidly expanding hyphal network, developed in some cultures from both spore sources.  相似文献   

14.
以感病泡桐组培苗提取的DNA为模板,采用PCR方法扩增pPaWBNy-2-ORF4的部分片段.将目的片段克隆到原核表达载体pGEX-4T-3,重组质粒pGEX-p2ORF4转化大肠杆菌Rosseta(DE3)菌株.IPTG诱导表达,分子量约为38 kDa的含GST标签的融合蛋白得到表达.切胶回收目的蛋白,免疫大白兔制备抗血清.间接ELISA测定抗血清的效价约为1:4096,免疫印迹实验显示:抗血清能够与原核表达的GST融合蛋白发生特异的免疫反应,与pPaWBNy-1-ORF5的原核表达蛋白无明显的交叉反应.利用制备的抗血清,在感病泡桐饲毒的茶翅蝽中检测到分子量约为18 kDa的蛋白条带,而在无菌茶翅蝽和感病泡桐组培苗中均未检测到,表明pPaWBNy-2-ORF4在饲毒的茶翅蝽中表达,而在感病泡桐组培苗中未表达或表达量低于检测水平.据此推测,该基因参与茶翅蝽传播泡桐丛枝植原体.  相似文献   

15.
Dieback and wilt, caused by Erwinia psidii (Ep), is one of the most important emergent diseases of Eucalyptus spp. in Brazil. Currently, pathogen detection relies on isolation of bacteria from infected plant tissue and either identification based on morphological, physiological and biochemical tests or DNA amplification using the polymerase chain reaction (PCR), which in many cases is laborious and cumbersome. Considering the need for a simpler and more rapid, yet reliable, method for detecting the pathogen, we obtained a polyclonal antibody (anti‐Ep) and developed an agglutination test for specific detection of E. psidii. The antiserum was produced against the E. psidii strain LPF534 and tested against 101 E. psidii isolates from Eucalyptus spp.; three E. psidii isolates from Psidium guajava; 23 Ralstonia solanacearum and 18 Xanthomonas axonopodis isolates pathogenic to Eucalyptus spp.; and seven endophytic isolates from Eucalyptus spp., three of which are phylogenetically related to the genus Erwinia. Results of direct ELISA indicated that a concentration as low as 3.5 µg/ml of the anti‐Ep antibody was able to detect the E. psidii antigen and that the antibody did not cross‐reacted with other bacteria pathogenic and non‐pathogenic to Eucalyptus spp. In the agglutination test, the anti‐Ep antibody showed positive reaction with all strains of E. psidii tested whereas cross‐reaction with none of the strains that belong to other taxonomic groups was observed. The agglutination test showed a detection limit of 105 colony‐forming units (CFU)/ml, and its specificity was the same as that obtained by PCR amplification using E. psidii‐specific primers. These results demonstrate that the agglutination test developed here is a useful tool for specific, fast and inexpensive detection of E. psidii although only operational on pure bacterial suspensions and not yet directly from infected tissues.  相似文献   

16.
Khasa  P.D.  Sigler  L.  Chakravarty  P.  Dancik  B.P.  Erickson  L.  Mc Curdy  D. 《New Forests》2001,22(3):179-197
The effect of three levels of fertilizer on thegrowth of three species of containerized-grownconifer seedlings (Pinus contorta, Picea glauca, and Picea mariana) and twospecies of bare-root conifer seedlings (Pinus sylvestris and Larix sibirica),and on the colonization of these seedlings bysix species of ectomycorrhizal fungi (Hebeloma longicaudum, Laccaria bicolor,Paxillus involutus, Pisolithustinctorius, Rhizopogon vinicolor andSuillus tomentosus), was studied. Thegrowth of the seedlings in both container-grownand bare-root nurseries increased as the levelsof fertilizer increased. For better seedlinggrowth and environmental quality it may be possible to reduce the level of fertilizers in commercial nurseries upto 33% by using selected mycorrhizal fungi.Ectomycorrhizal colonization in all seedlingswas not affected by fertilizer levels. Hebeloma longicaudum, L. bicolor, P.involutus, and P. tinctorius formedwell-developed ectomycorrhizae, whereasectomycorrhizal development by R.vinicolor and S. tomentosus was poor.Native mycorrhizal fungi colonizednon-inoculated control seedlings; however,their colonization was always lower than withinoculated fungi.  相似文献   

17.
In February 2015, an unexpected windstorm downed five hectares of a European black pine Pinus nigra subsp. laricio forest formation located close to Vallombrosa, Florence (Central Italy). In the following spring, an extensive survey was conducted in the area. Felled trees, stumps and all the suitable plant material were screened for the presence of the pinewood nematode (PWN), Bursaphelenchus xylophilus, by sampling wood and bark. Bark beetles were then collected from the gallery systems on the inner side of bark samples and observed in the laboratory. The following bark beetles were morphologically identified: Ips sexdentatus, Orthotomicus erosus, O. laricis and Pityogenes bidentatusa. The dissection of Ips sexdentatus allowed the extraction of numerous nematodes that were morphologically and molecularly identified as Ektaphelenchoides pini. Conversely, only few nematode specimens were isolated from either pine bark or wood. These individuals could be only molecularly identified and belonged to an undescribed nematode taxon. Even though no PWN was recorded in the investigated sites, our survey allowed the detection of a new association between E. pini and I. sexdentatus on P. nigra.  相似文献   

18.
van der KAMP  B.J. 《Forestry》1968,41(2):189-198
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19.
白蜡虫脂酰辅酶A还原酶（FAR1）参与了体表蜡泌物的形成过程,为了进一步研究FAR1的功能,通过预测分析基因 far1 编码的蛋白结构,选取亲水性强、特异性好的一段合成多肽作为抗原肽,免疫新西兰大白兔制备多克隆抗体,并以BCA蛋白浓度试剂盒测定抗体浓度,通过SDS-PAGE考马斯亮蓝染色观察纯化抗体的纯度,以ELISA检测抗体效价。结果表明,纯化所得的多克隆抗体纯度高,抗体浓度0.7 mg·mL-1,抗体效价为 1：512 000,为后续FAR基因功能的研究奠定基础。  相似文献   

20.
Zusammenfassung In Süddeutschland (Regierungsbezirke Oberfranken, Mittelfranken, Oberpfalz und Pfalz) tratenBupalus piniarius L.,Panolis flammea Schiff. undLymantria monacha L. von 1810–1970 immer wieder stark auf, w?hrendDendrolimus pini L. undDiprion pini L. nur in bestimmten Zeitabschnitten und relativ selten vorkamen. Die Hauptschadgebiete dieser Arten werden kartographisch dargestellt.
Pine insects in South-Germany: A historical-entomological study
Summary In South-Germany (administrative areas of Oberfranken, Mittelfranken, Oberpfalz and Pfalz),Bupalus piniarius L.,Panolis flammea Schiff. andLymantria monacha L. occurred frequently during 1810–1970, whileDendrolimus pini L. andDiprion pini L. appeared only occasionally and at moderate intensities. The distribution of these insect pests is presented in maps.

Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   

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