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Behrouz Golhasan Mehrab Esmaeili Yiwu Fang Joaquín Abolafia Ramin Heydari 《Forest Pathology》2019,49(6)
Ektaphelenchoides maafiae n. sp. was isolated during a survey of nematodes associated with bark samples of an oak tree (Quercus castaneifolia) in Gorgan, Golestan Province, northern Iran. The new species has a body length of 480–546 μm (in females) and 431–480 μm (in males). The cuticle is weakly annulated, with three lateral lines. Lip region offset. The stylet is 13–15 μm long without basal swellings. The excretory pore is located at the level of the metacorpus base to slightly posterior, and hemizonid is at 15–17 μm posterior to the excretory pore. The post‐uterine sac is short, 6–8 μm long. Spicules having rounded condylus, rostrum short, conical with bluntly pointed tip, a cucullus (apophysis) presented on the dorsal distal end. Male tail bearing four (2 + 2) caudal papillae, conical, with sharply pointed terminus. The new species is close to four known species of the genus, including E. hunti, E. ruehmi, E. caspiensis and E. poinari, but differs from them by body size, shape of tail terminus, stylet length, shape and size of spicules, length of post‐vulval uterine sac and number of caudal papillae. Phylogenetic analysis based on small subunit (SSU) and partial large subunit (LSU) sequences of rDNA confirmed its status as a new species. 相似文献
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An infestation of mangrove forests with Neodolichodorus persiangulfus n. sp. in southern Iran is reported. This paper is the first to report a representative species of the genus in the country. The new species was characterized by 2,120 (1795–2400) µm long females, and 1755 (1533–2019) µm long males, a continuous to slightly offset cephalic region separated from the rest of the body by a shallow depression, having 5–7 annuli and a distinct labial plate, a lateral field with four lines, the outer ones crenate, irregularly areolated in anterior and posterior body region, 79 (66–85) μm long female stylet, a didelphic‐amphidelphic female reproductive system with asymmetric sclerotized vaginae, phasmids 5–10 annuli behind the anus, female tail elongate conoid, suddenly narrowing at 5–12 annuli posterior to anus and males with trilobed bursa, 52.5 (47–58) μm long spicules and 21.5 (18–27) μm gubernaculum. With the elongate‐conoid female tail and c? >1.2, the new species is close to five known species of the genus: N. brevistylus, N. leiocephalus, N. paralongicaudatus, N. rageshi and N. sinensis, but is distinguished from them by the morphology of the female tail, areolation type of the lateral field, position of hemizonid and phasmid and morphometric data. Molecular phylogenetic analyses using sequences of the near full‐length fragment of the small and the D2‐D3 expansion segments of the large subunit ribosomal DNA (SSU and LSU rDNA D2‐D3) revealed the new species placed in a clade including one isolate of Neodolichodorus sp. and some species of Globodera, Heterodera and Rotylenchulus with 0.89 Bayesian posterior probability (BPP) in SSU phylogeny. The only available SSU sequence of the genus was the tentative closest relative to the new species in the inferred SSU tree. In the reconstructed LSU phylogenetic tree, N. persiangulfus n. sp. formed a poorly supported clade with Rotylenchulus spp. in Bayesian inference (BI), and the only other available D2‐D3 sequence of the genus occupied a distant placement to the new species. 相似文献
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Yousef Moradi‐Amirabad Heshmat Rahimian Valiollah Babaeizad Sandra Denman 《Forest Pathology》2019,49(4)
Decline diseases of forest trees are complex syndromes not attributable to single causal factors. In Iran, symptoms of decline disease have been observed in a number of native forest species including Quercus castaneifolia (chestnut‐leaved oak), Q. brantii (Persian oak) and Carpinus betulus (hornbeam). The symptoms are prevalent in the northern forests and the Zagros mountain forests. There are parallels between the disease in Iran and acute oak decline (AOD) reported in the UK, specifically the presence of weeping cankers, which have been attributed to a polybacterial complex wherein Brenneria goodwinii is considered a key necrogen. Based on the AOD symptomatology, and as a first step towards discovering potential causal agents of the stem weeping symptoms of affected trees in Iran, necrotic tissues were tested primarily for the presence of B. goodwinii. Symptomatic Q. castaneifolia and C. betulus from the Mazandaran Province and symptomatic Q. brantii from Kohgiluyeh and Boyerahmad Province were sampled. Isolation and culture on a selective medium yielded uniform bacterial colonies. Isolates were characterized using phenotypic and genotypic (DNA sequencing) tests. The isolates were phenotypically identical to members of Pectobacteriaceae and Yersiniaceae, specifically Brenneria and Rahnella spp. The nucleotide sequences of the 16S rRNA and housekeeping genes gyrB, infB and atpD (MLSA) amplified via PCR demonstrated that the isolates from the trees in Iran were indeed B. goodwinii, B. roseae subsp. roseae, Rahnella victoriana and an unknown species of Brenneria. Most bacteria isolated from non‐symptomatic trees were Gram‐positive, and Pseudomonas spp. were dominant, but bacterial species isolated from the diseased trees were not detected in healthy trees. Hypersensitivity response tests were positive, but inoculation on saplings was more variable with internal necrosis developing only once in the test period. Therefore, further testing is required. This is the first report of the incidence of B. goodwinii, B. roseae subsp. roseae, R. victoriana and Brenneria sp. associated with acute oak decline‐like symptoms on Q. castaneifolia, Q. brantii and C. betulus across the western forests of Iran and in the world. 相似文献
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Needles of Pinus sylvestris with and without symptoms of Cyclaneusma needle cast, from the west of Poland, were examined for abundance and diversity of fungi using Illumina sequencing. Fungal communities were dominated by Ascomycota (93.6%–98.6% of OTUs). Basidiomycota and non‐culturable fungi were less frequent. Needles were colonized by 260 taxa. Ascomycota, Basidiomycota and Glomeromycota were represented by 149, 39 and 1 taxa. Abundance of fungi was least in 1.5‐year‐old needles attached to twigs and greatest in fallen 2‐year‐old needles. Fungal communities had least diversity in 1.5‐year‐old needles and most diversity in 0.5‐year‐old needles of current growth. It was found that (a) the most common fungi were the needle pathogens Cyclaneusma minus, Lophodermium spp. and Sydowia polyspora; (b) less common potential pathogens were Cenangium ferruginosum, Coniothyrium complex, Desmazierella acicola, Neocatenulostroma germanicum and species in the genera Neodidymelliopsis, Pestalotiopsis, Phoma, Pleurophoma and Pyrenochaeta; (c) common primary or secondary saprotrophs included species of Alternaria, Aureobasidium, Beauveria, Cladophialophora, Cladosporium, Epicoccum, Exophiala, Lecanicillium, Penicillium, Cryptococcus and Kwoniella; (d) Lophodermium was represented mostly by Lophodermium pinastri which occurred 4–72 times more frequently than Lophodermium seditiosum; (e) frequencies of C. minus and C. ferruginosum were lower in the 0.5‐year‐old symptomless needles, increased in the symptomatic and symptomless 1.5‐year‐old needles and decreased after needle fall; (f) frequency of L. seditiosum was highest in 0.5‐year‐old needles; (g) frequency of L. pinastri increased with needle age whereas S. polyspora increased after needle fall; (h) lower frequency of L. pinastrii was associated with higher frequency of S. polyspora. It was concluded that Cyclaneusa needle cast in Poland may be caused by C. minus accompanied by C. ferruginosum, L. seditiosum, L. pinastrii and S. polyspora. Participation of Coniothyrium spp., Epicoccum nigrum, Pestalotiopsis spp. and Phoma spp. in the disease progress cannot be excluded. 相似文献
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Host specificity of co‐infecting Botryosphaeriaceae on ornamental and forest trees in the Western Balkans 
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下载免费PDF全文 The Botryosphaeriaceae is a diverse family of endophytes and fungal pathogens of mainly woody plants. We considered the host range and distribution of these fungi by sampling diseased ornamental and forest trees and shrubs in Serbia, Montenegro, Bosnia and Herzegovina, spanning a Mediterranean and a Continental climatic region. In total, ten Botryosphaeriaceae species were identified in the Western Balkans and with the exception of Sphaeropsis visci and Phaeobotryon cupressi, which occurred on one host, all the species had a broader host range. Phaeobotryon cupressi was found only in the Mediterranean region and S. visci, Dothiorella sp., Dothiorella sarmentorum and Diplodia seriata were present only in the Continental region. Pathogenicity tests were conducted on a variety of hosts from which the Botryosphaeriaceae species were isolated. These included leaves and/or stems of seedlings of 21 hosts, and cut leaves and/or branches of six hosts. Moreover, stems of seedlings of Chamaecyparis lawsoniana, Cedrus deodara, Picea omorika, Pinus patula and Eucalyptus grandis were inoculated as hosts from which some or all of the Botryosphaeriaceae species used for inoculation were not isolated. Inoculations showed that the majority of these fungi could also co‐infect hosts other than those from which they were isolated. The results suggest that most of the species have broad host ranges and can potentially cause disease on a broad range of tree species under certain conditions. 相似文献
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In August 2011, fungal endophytes were isolated from fine (0.1–0.5 cm diameter) and structural (0.6–2.0 cm) roots from eighteen Q. robur trees at six sites in a Q. robur‐dominated forest displaying symptoms of oak decline. Five sites were subjected to periodic flooding for 3 months in 1997 and 1 month in 2010. Fungal colonization was detected in 94% of 1296 root fragments examined. Fungi representing 126 taxa from Zygomycota (four species), Ascomycota (117 species) and Basidiomycota (five species) were isolated using culture‐based methods and identified by morphotyping and sequencing of the ITS 1 and 2 rDNA. The most frequent eudominants (with colonization frequencies ≥10%) were Aspergillus spp., Cosmospora sp., Ilyonectria radicicola, Pezicula radicicola, Pyrenochaeta cava and six species of Trichoderma. Species composition did not vary greatly between sites, but only 3% of species occurred in all sites. Number of species was higher in roots subjected to floods. Eudominants and dominants present only on flooded sites included Aspergillus spp., Chaetomium globosum, Cosmospora sp., I. radicicola, Sporothrix inflata, Trichoderma harzianum, T. pubescens and T. virens. Structural roots were usually colonized by a higher number of species than fine roots. The majority of species detected belong to Class 2 NC‐endophytes. Pezicula radicicola and Phialocephala fortinii belong to Class 4 NC‐endophytes. 相似文献
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Zeinab Mirzaie Fouladvand Ebrahim Pourjam Natsumi Kanzaki Robin M. Giblin‐Davis Majid Pedram 《Forest Pathology》2019,49(2)
Basilaphelenchus gorganensis n. sp. is described and illustrated from wood and bark of a dead tree from northern Iran. The new species is characterized by female body length (415–559 µm), three‐lined lateral fields, a sclerotized cephalic vestibule and cephalic framework, thin stylet with three elongate backwardly directed knobs, small spherical to oval metacorpus, with small and posteriorly located valve, simple vulva without any flap apparatus, 59‐ to 79‐µm‐long post‐vulval uterine sac, functional rectum and anus and dorsally convex, ventrally concave, usually ventrally bent conical female tail with a sharp tip. Males are common, apparently functional and characterized by well‐curved spicules, three pairs of small caudal papillae and no bursa at tail tip. Molecular phylogenetic inferences using partial sequences of small and large subunit ribosomal RNA genes (SSU and LSU rDNA) from different isolates of the new species revealed it differs from currently sequenced species and belongs to the Tylaphelenchinae clade. 相似文献
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Yuan Cheng Wenxia Zhao Ruozhu Lin Yanxia Yao Shaoshuai Yu Zhongfu Zhou Xuechao Zhang Yahui Gao Wenxia Huai 《Forest Pathology》2019,49(5)
Wild apple forests in the Tian Shan Mountains in north‐western China have been adversely affected by an unknown disease in recent years. Symptoms attributed to this disease that affects wild apple trees include xylem browning and dieback which are suggestive of infection by Fusarium species. Therefore, the research team conducted the first survey for Fusarium in the afflicted wild apple forests. Twig samples with symptoms of xylem browning and dieback were collected in the Xinyuan, Gongliu, Yining and Huocheng Counties of Xinjiang Uighur Autonomous Region in China. Based on phylogenetic analyses and morphological observation, sixty strains of Fusarium accounted for 48% of the total number of fungi isolated from samples were subsequently classified into six species including twenty‐four F. avenaceum, seventeen F. solani, ten F. tricinctum, five F. proliferatum, two F. sporotrichioides and two unfamiliar Fusarium sp. 1. The five previously known species of Fusarium were then tested for pathogenicity to leaves and twigs in vitro. The results indicated that all of the species, except for F. tricinctum, can cause obvious lesions on the leaves of host plants and on the twigs of Fuji and wild apple. This is the first report of Fusarium species pathogenicity in Xinjiang wild apple forests, confirming a new host for these pathogens in this study. 相似文献
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I. Matsiakh H. T. Doğmuş‐Lehtijärvi V. Kramarets A. G. Aday Kaya F. Oskay R. Drenkhan Steve Woodward 《Forest Pathology》2018,48(2)
Dothistroma needle blight (DNB) is among the most serious foliar diseases affecting Pinus spp. globally. Infected needles were collected from potential host species in four locations in western Ukraine and in four locations in eastern Georgia during spring–summer 2015 to update the knowledge on pathogen distribution in these countries. Dothistroma spp. were detected using isolation, sequencing and species‐specific priming (SSPP) PCR. Two new hosts for Dothistroma spp. were recorded in western Ukraine: D. septosporum on Pinus nigra var. australica and D. pini on P. nigra var. mollet. D. septosporum was found on 15‐year‐old P. strobus in western Ukraine. New hosts for D. septosporum were recorded in Georgia on 5‐ to 10‐year‐old naturally regenerated P. sylvestris var. hamata and on 40‐ to 50‐year‐old P. ponderosa trees. D. pini was found for the first time in Georgia on 30‐ to 40‐year‐old P. nigra trees. The work confirmed the presence of both D. septosporum and D. pini in western Ukraine and Georgia, and demonstrated new hosts for both Dothistroma species. 相似文献
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This preliminary study identified the fungal endophytes of Sitka spruce (Picea sitchensis) in four Scottish plantations, analysed their recruitment possibilities and community structure across the sites, and identified the possible origins of the endophytes in this non‐native host. Although Sitka spruce is native to north‐western North America, it comprises a huge portion of Scottish forestry and is an economically vital timber tree. Needles from two age classes were collected and cultured for emerging endophyte isolates. Using a combination of morphological features and genetic sequencing of the nuclear ribosomal ITS regions of representative morphological types, 57 morphotypes were recorded which represented at least 15 different species, including a hypothesized sister species to the pathogen of Pseudotsuga menziesii in North America and Europe, Nothophaeocryptopus gaeumannii (previously P. gaeumannii) that was present at all sites tested. Diversity, recruitment, site, needle age and needle part effects are discussed. The phylogeny of Nothophaeocryptopus based on analysis of combined ITS and Tub2 sequence data is given in order to assess the relationship of the unknown endophyte to the Douglas fir pathogen N. gaeumannii. 相似文献
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In addition to Hymenoscyphus fraxineus, two fungi identified as Diaporthe eres aff. and Fusarium sambucinum aff. were also isolated from necrotic bark lesions on declining one‐year‐old Fraxinus excelsior in a forest stand in Montenegro. To examine their involvement in ash decline, a pathogenicity test was performed using under bark inoculations on one‐year‐old Fraxinus excelsior. Hymenoscyphus fraxineus was included as comparison. All three fungal species proved highly pathogenic towards one‐year‐old seedlings although lesion sizes differed significantly between the different species. Hymenoscyphus fraxineus was most aggressive, followed by F. sambucinum aff., while D. eres aff. caused the smallest lesions. This study demonstrates for the first time the ability of isolates in the D. eres and F. sambucinum species complexes to cause decline on one‐year‐old common ash seedlings. 相似文献
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The epidemic outbreak in northern Europe of Neonectria neomacrospora, the causal agent of dieback in Abies spp., led the European and Mediterranean Plant Protection Organization (EPPO) to include the pathogen on its alert list in 2017. Effective monitoring of this pathogen calls for a rapid and sensitive method of identification and quantification. A probe‐based real‐time PCR (qPCR) assay based on the β‐tubulin gene was developed for the detection and quantification of N. neomacrospora in infected wood samples, and directly for ascospores. This study presents the first published species–specific molecular detection assay for N. neomacrospora. The analytical specificity was validated on taxonomically closely related fungal species as well as on 18 fungal species associated with the host (Abies sp.). The analytical sensitivity was tested on naturally infected wood, on purified pathogen DNA in a matrix of host DNA and on N. neomacrospora ascospores for detection of airborne inoculum. The latter was tested both with a DNA extraction step prior to qPCR and without DNA extraction by direct qPCR on collected ascospores. The assay was specific to N. neomacrospora, with a sensitivity of 130 fg purified DNA, or 10 ascospores by direct qPCR. Omitting DNA extraction and amplifying directly on unpurified ascospores improved assay sensitivity significantly. 相似文献
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W.‐x. Huai G. Tian E. M. Hansen W.‐x. Zhao E. M. Goheen N. J. Grünwald C. Cheng 《Forest Pathology》2013,43(2):87-103
Phytophthora species were surveyed by collecting soil samples and placing bait leaves in selected streams during June–October in the years 2005, 2006 and 2010 at three sites in oak forests in Diqing Tibetan Autonomous Prefecture of NW Yunnan province, China. Seventy‐three isolates of Phytophthora spp. were recovered from 135 baited leaf samples and 81 soil samples. Eight Phytophthora species were identified by observation of morphological features and ITS1‐5.8S‐ITS2 rDNA sequence analysis. The eight taxa included two well‐known species P. gonapodyides and P. cryptogea, two recently described species P. gregata and P. plurivora, two named but as yet undescribed taxa, P. taxon PgChlamydo and P. taxon Salixsoil, and two previously unrecognized species, Phytophthora sp.1 and P. sp.2. The most numerous species, P. taxon PgChlamydo, and the second most abundant species, P. taxon Salixsoil, were recovered at all three sites. Phytophthora cryptogea was detected only once at site Nixi. Phytophthora gregata and P. sp.2 were isolated from a stream only at site Bitahai, while the other three species were each found at two sites. Phylogenetic analysis revealed that the isolates belonged to three ITS clades, one species including six isolates in clade 2, six species including 66 isolates in clade 6 and one species in clade 8. There was a relatively rich species and genetic diversity of Phytophthora detected in the investigated regions where the forest biotic and abiotic factors affecting the growth and evolution of Phytophthora populations were diverse. 相似文献
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Sabyasachi Banerjee Seema Singh Shailesh Pandey Maneesh S. Bhandari Amit Pandey Krishna Giri 《Forest Pathology》2020,50(2)
Wilt disease caused by Fusarium solani is a serious constraint to Dalbergia sissoo (shisham) plantations in northern India. In this study, the antagonistic potential of 40 bacterial isolates recovered from rhizophere soil of healthy shisham trees, and a well‐characterized Trichoderma species (Trichoderma virens) were tested for their possibility as biocontrol agents for F. solani. Two promising isolates (S1 and S15) were identified which inhibited pathogen growth, caused chitin degradation, produced siderophores and solubilized phosphate in vitro. Isolate S15 scored highest for hydrogen cyanide (HCN) production while isolate S1 was a non‐HCN producer. These two isolates were identified as Serratia marcescens (S1) and Pseudomonas azotoformans (S15) following sequence analysis of 16S rDNA. In dual culture assays, T. virens caused 80% inhibition of mycelial growth of the test fungus. The three selected antagonists when tested in planta in the glasshouse completely suppressed production of wilt symptoms on 12‐month‐old shisham plants. Further work is needed to ascertain the potential of these isolates to be used as biocontrol agents to manage shisham wilt under field conditions. 相似文献
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Response of swamp bay,Persea palustris,and redbay,P. borbonia,to Raffaelea spp. isolated from Xyleborus glabratus 下载免费PDF全文
下载免费PDF全文 T. J. Dreaden A. S. Campbell C. A. Gonzalez‐Benecke R. C. Ploetz J. A. Smith 《Forest Pathology》2017,47(1)
Laurel wilt is a devastating invasive disease of members of the Lauraceae plant family. It is caused by the fungus Raffaelea lauricola, which is a nutritional symbiont of its ambrosia beetle vector, Xyleborus glabratus. In the United States, six Raffaelea spp., in addition to R. lauricola, have been recovered from mycangia of X. glabratus. We compared the response of two laurel wilt suspects, swamp bay (Persea palustris) and redbay (Persea borbonia), to five of these species, another undescribed Raffaelea sp., and R. lauricola. Six weeks after inoculation, only R. lauricola caused significantly greater symptoms than water inoculations. The fungi varied in their ability to move systemically and be recovered from the host at the end of the experiment. Stem hydraulic conductivity was decreased by R. lauricola, but none of the other taxa. Although the roles these fungi play in the life cycle of X. glabratus are not known, they do not appear to be pathogens on these host tree species. 相似文献
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Amani Bellahirech Maria L. Incio Steve Woodward Mohamed L. Ben Jama Filomena Nbrega 《Forest Pathology》2019,49(1)
Ambrosia beetles, including Platypus cylindrus, commonly act as vectors of Ophiostomatales. In an investigation of fungi associated with P. cylindrus, several species of Ophiostomatales were identified, including two species of Ophiostoma s. str. These two species were characterized based on comparisons of DNA sequences of the internal transcribed spacer regions including the 5.8S gene of rDNA and β‐tubulin gene. Two distinct clades were discernable in the phylogenetic trees, supported by high bootstrap values. One clade included the species Ophiostoma tsotsi, reported herein for the first time in Tunisia, and the species Ophiostoma quercus. 相似文献