松材线虫和拟松材线虫繁殖能力差异研究

松材线虫作为外来入侵种,逐步取代拟松材线虫占据生态位。初步研究表明这可能与两种线虫的繁殖能力差异关系密切。本研究采取了两种方法,即离体条件竞争试验和体内竞争试验比较二者繁殖力。结果表明,松材线虫的繁殖水平明显高于拟松材线虫。松材线虫和拟松材线虫混合物长时间培养后,松材线虫逐步竞争淘汰拟松材线虫。除此以外,离体培养和体内竞争结果均表明,竞争条件下松材线虫的繁殖力高于非竞争条件。     

松材线虫和拟松材线虫家系建立及其致病力测定

遗传背景相对一致、致病力稳定的植物线虫材料是开展其遗传学和致病机制研究的基础。对分别来自中国和日本的4个松材线虫(Bursaphelenchus xylophilus)和1个拟松材线虫(B.mucronatus)虫株采用两条幼虫配对在葡萄孢(Botrytis cinerea)基质上进行单异活体共培养的方法获得了若干个遗传背景相对一致线虫家系,家系成功率为13.3%～20%。线虫家系在盛有灰葡萄孢培养基质的、直径为9 cm的培养皿上取食完全所需的时间为10～44天。对不同家系进行了致病力测定表明,家系间的致病力分化明显。综合考虑感病率、感病指数、接种松苗死亡历期等指标,其中松材线虫家系AN19#F1的致病力最强,而拟松材线虫虫株AN5#所建家系都没有表现致病力。     

松材线虫和拟松材线虫不同株系线粒体DNA RAPD分析

对松材线虫7个株系和拟松材线虫2个株系的线粒体DNA随机扩增多态性分析结果显示,松材线虫和拟松材线虫种间和种内都表现出很大的变异性,但种间变异明显大于种内变异,因而支持将松材线虫和拟松材线虫划分为两个不同的种.两个拟松材线虫株系(法国株系和日本株系)之间的相似值和松材线虫各株系间的相似值极为接近,由此看来,这两个株系的变异为种内变异,应同属于一个种.聚类分析的结果表明,松材线虫和拟松材线虫系两个明显不同的类群,即松材线虫类群和拟松材线虫类群.松材线虫类群又分为两个亚组,一个是以日本株系为代表,另一个是以北美洲(美国和加拿大)株系为代表.     

松材线虫和拟松材线虫雄虫交合伞形状的比较

松材线虫和拟松材线虫雄虫交合伞形状的比较刘伟，杨宝君关键词松材线虫，拟松材线虫，雄虫交合伞松材线虫病是松树的一种毁灭性病害。病原松材线虫ＢｕｒｓａｐｈｅｌｅｎｃｈｕｓｘｙｌｏｐｈｉｌｕｓＮｉｃｋｌｅ（简作Ｂｘ）的形态与非病原拟松材线虫Ｂ．ｍｕｃｒｏｎ...     

楸树根结线虫的调查和鉴定

连云港市楸树根结线虫发病率达93.3—100％,感染指数53.4—57.5。经酯酶凝胶电泳、鉴别寄主试验、虫体测量及会阴花纹观察,确认该线虫是南方根结线虫Meloidogyne incognita 2号小种。     

国内部分地区松材线虫和拟松材线虫基因多态性的RAPD分析

采用SDS法提取线虫基因组DNA,分别选取了6种随机引物对部分地区的10株松材线虫和10株拟松材线虫进行随机扩增和亲缘关系比较。RAPD的结果可以明显区分松材线虫和拟松材线虫,与形态学分类相吻合。聚类分析的结果也表明,线虫种内和种间均存在差异,但种间差异明显大于种内差异,同种线虫在同一地区或临近地区的同源性明显高于其它地区,同一地区内寄主对线虫种类分布的影响较小。该方法具有所需样品量少、检测灵敏度高、结果准确等优点,为松材线虫种群的亲缘关系、传播途径及其检测防疫等方面提供一种灵敏、可靠的研究方法。     

美国密苏里州和松材线虫有关的昆虫

已发现鞘翅目中有七种昆虫携带松材线虫Bursaphelenchus xylophilus。从松材线虫为害的欧洲赤松上羽化出来的卡墨天牛Monochamus carolinensis(olivier)(鞘翅目天牛科),每头平均携带线虫19152(±16421)条。没有一个其他昆虫携带线虫在300条以上的。卡墨天牛携带的线虫85％是在胸部,并且主要在后胸节。用扫描电子显微镜确定从受害树羽化出来的天牛呼吸系统内的线虫。     

美国和日本松材线虫情况的比较

前言在日本,松材线虫Bursaphelenchus xylophilus(steiner and Buhrer)Nickle(以前学名为B.lignicohus Mamiya and kiyohara)引起松树枯死。最近三十年间,在日本本地松(日本赤松     

植物线虫的采集、分离和固定

植物线虫的采集、分离及固定方法是植物线虫研究工作的基础。由于实验室条件的差异,所用的方法也不尽相同,现介绍几种常用方法。     

Fungal–copper interactions in wood examined with large field of view synchrotron-based X-ray fluorescence microscopy

ABSTRACT

The goal of this study was to demonstrate how synchrotron-based X-ray fluorescence microscopy (XFM) can be used to better understand the mechanisms of copper tolerance in wood decay fungi. Copper is a major component in commercial wood preservatives as it is toxic to many wood decay fungi. However, certain fungi are copper tolerant and can attack preservative-treated wood, resulting in structural damage to treated wood members. Here we used large-field XFM to visualize six different elements (K, Ca, Mn, Fe, Cu, and Zn) in the mycelia and wood inoculated with four different species of brown rot wood decay fungi. Wood blocks were partially dipped into a solution of copper sulfate, exposed to fungi in malt extract agar petri dish assays for nine weeks, and then imaged and compared to blocks that were partially dipped in water. The blocks were imaged immediately adjacent to an end-matched control that was placed in malt extract agar petri dish assays for 9 weeks, but not exposed to the fungi so that the differences in the elemental distributions could be directly compared. The colonized wood and mycelia were rich in K, Ca, Mn, and Fe; however, the elements and the spatial distribution in the mycelia and wood differed across fungal species. The most interesting results were the maps showing the copper distribution. While three of the four fungi grew on the copper-rich region of the wood, only one species, Fibroporia radiculosa, dramatically reduced the copper concentration in the region of fungal growth.     

Identification of wood‐decay fungi and assessment of damage in log depots of Western Black Sea Region (Turkey)

The aim of this study was to determine and quantify the wood‐decay fungi found on logs of forest tree species (beech, oak, hornbeam, Scots pine and fir) stored in log depots located in six different provinces in the Western Black Sea Region of Turkey. Additionally, it was aimed to determine the natural durability of some important wood species against the most commonly detected wood‐decay fungi. Eighteen families, 31 genera and 45 species belonging to the division Basidiomycota were detected; Antrodia crassa was identified for the first time in Turkey. The abundance of Panus neostrigosus, Polyporus meridionalis, Trametes hirsuta, T. versicolor and Stereum hirsutumincreased significantly with the holding time of the logs (r = 0.99, 0.87, 0.53, 0.57 and 0.78, respectively, p < 0.05). The majority of the fungal species were detected on logs stored in depots for 4–6 years (66%). The percentage of fungal species found on the logs with a holding time of three years or less was 29%, whereas the percentage for those detected on logs stored for seven or more years was 31%. Among the wood species, the greatest number of fungal species (29) and highest amount of fungi (2,539) occurred on beech wood. Natural durability tests showed that T. versicolor caused the greatest loss of wood mass, with an average of 23%. Field studies and natural durability tests performed in the laboratory showed that beech wood lost the most mass among the timber species studied.     

Diversity and community structure of wood-inhabiting fungi found in Japanese wooden houses analyzed by the next-generation sequencing

The diversity and community structures of wood-inhabiting fungi in 16 decayed wood samples from ten wooden houses in Japan were analyzed using a next-generation sequencing (NGS) to determine the fungi responsible for wood decay. DNA of fungi in decayed wood was extracted directly, the internal transcribed spacer (ITS) region in ribosomal DNA (rDNA) was amplified by polymerase chain reaction (PCR), and then, sequences of tagged ITS fragments were analyzed by NGS. Results of sequencing indicated that 68 species of ascomycetes, 37 species of basidiomycetes, and one fungus each from Mortierellales and Mucoromycetes were detected. The fungal community structures showed diversity and included various species of ascomycetes. A microscopic examination of cell wall structure in decayed wood samples suggested that some ascomycetes were soft-rot fungi. Heat map analysis indicated that the similarity in the structures of fungal communities was influenced to a greater extent by the wood species of samples than where they were used as a component.     

Mycologg: a new accelerated test method for wood durability above ground

If not properly handled, selected and protected, wood will be degraded by bacteria, fungi and also insects. In order to ensure service life, durability tests are needed. Most accelerated laboratory tests on wood durability are focused either on fungi attacks or the uptake of moisture. Accelerated field tests in ground contact are of limited use since they could be difficult to reproduce and are sensitive to the characteristics of the soil in which the wood is placed. In addition, the results cannot be directly transferred to wood in use above ground because such wood is subjected to different set of conditions. The Mycologg is a new accelerated test method for estimating the durability of wood in above ground applications. The Mycologg allows the test panels to be subjected to the discolouring fungi and different RH (relative humidity) cycles simultaneously. Every 30 min, the temperature, the RH, and the moisture content in each test panel are measured and saved in special software. This allows for a constant update of the moisture patterns during a fungi attack. A trial was made with Scots pine (Pinus sylvestris) heartwood samples, where fungal growth after 6, 8 and 10 weeks in the Mycologg were compared to weather exposure of duplicate samples after 12, 16, and 26 months. The results showed that 10 weeks into the Mycologg accelerated test method corresponds well to real-time weather exposure with respect to fungal discolouration.     

Polypores on Spruce in Northeast China

Poroid species of wood-inhabiting fungi growing on spruce (Picea koraiensis Nakai or Picea yezoensis (Sieb. & Zucc.) Carriere) in Northeast China were investigated during 1993-2002, and 71 species were recorded from these trees or their wood. Skeletocutis lilacina A. David & Jean Keller and Skeletocutis papyracea A. David are new to China. Fomitopsis pinicola (Sw.:Fr.) P. Karst., Onnia leporina (Fr.) H. Jahn, Perenniporia subacida (Peck) Donk, Phaeolus sckweinitzii (Fr.:Fr.) Pat., Phellinidium sulphurascens (Pilat) Y.C. Dai and Phellinus yamanoi (Imazeki) Parmasto are the pathogens on the two trees. Among the 71 species 18 species (ca. 25% of all species) are considered as rare species, 34 species (48% of all species) are the occasional species, and 19 species (27% of all species) are the common species.     

Wood‐rotting basidiomycetes are a minor component of fungal communities associated with Acacia hybrid trees grown for sawlogs in South Vietnam

Acacia hybrid (Acacia mangium × Acacia auriculiformis) clones are widely planted in Vietnam with a total of approximately 400,000 ha to meet the demand for pulpwood, sawn timber and wood chip exports. Silvicultural techniques such as pruning and thinning have been applied to improve productivity and sawlog quality of Acacia hybrid plantations. However, those techniques may also create opportunities for wood decay fungi to enter the Acacia hybrid stems through wounds and cause stem defects that reduce sawlog quality and the value of the plantation. The presence of fungal decay agents in Acacia hybrid trees was examined in two Vietnamese plantations. In July 2011, just prior to a second thinning, discoloured wood samples were taken from a three‐year‐old Acacia hybrid plantation at Phan Truong Hai for the isolation of fungi. In July 2012, approximately 18 months after pruning and thinning treatments, discoloured wood samples were taken from a three‐year‐old Acacia hybrid plantation at Nghia Trung for the isolation of fungi. DNA sequencing of the rDNA ITS identified the isolates. In May 2015, approximately 4 years after thinning and fertilizer treatments, discoloured and decayed wood samples were taken from the above (7‐year‐old) Acacia hybrid plantation at Phan Truong Hai for fungal identification. DNA was extracted directly from discoloured and decayed wood samples and fungal rDNA ITS amplicons sequenced on a Roche 454 sequencer. The results showed that silvicultural treatments did not affect the fungal communities associated with discoloured and decayed wood of Acacia hybrid plantation at Phan Truong Hai. A total of 135 fungal species or OTUs (operational taxonomic units) were identified, including 82 members of Ascomycota and 52 Basidiomycota.     

酸碱度和松树基质对杀线菌Esteya vermicola菌丝体生长的影响

[目的]研究Esteya vermicola真菌适应的pH范围,并探讨松树成分对其生长的影响,以期为E. vermicola菌在松树体内的定植和林业重大病害松材线虫野外的生物防治提供理论支撑。[方法]选取E. vermicola CBS115803(EV115803)和E. vermicola CNU120806(EV120806)为试验对象,测试EV真菌适应的pH范围,并以35 a黑松不同器官组织配制培养基,探究EV菌的生长情况,观测各菌株生长速率、菌体量和产孢量。[结果]EV菌适应的pH值范围为5～13,菌体量在酸性条件下产生更多的气生菌丝。PDA中加入松树成分对EV菌有一定的刺激生长作用。在以松针、松树皮、松枝条为唯一营养来源时,EV菌生长茂盛。以木质部锯末为单一营养源时,EV菌生长缓慢。[结论]EV菌适应的pH值范围为5～13,EV菌耐碱性极强,且在加有松树各部位成分的培养基上生长,菌株EV120806对松树培养基的适应性更强,未来有望将EV菌定殖在松树中做为共生菌,摄食入侵的松材线虫,从而使松树具有内源的防控因子防控松材线虫。     

6种白腐菌腐朽前后的山杨木材酚酸种类和含量变化的高效液相色谱分析

研究阔叶树上的6种木材白腐菌火木层孔菌、粗毛盖菌、偏肿拟栓菌、三色革裥菌、冬拟多孔菌和血红密孔菌对山杨材腐朽前后木材中游离酚酸种类和含量的变化情况.结果表明:受6种白腐菌腐朽后的山杨木材中酚酸的种类和含量各不相同,在山杨材被分解120 d后,偏肿拟栓菌、三色革裥菌、血红密孔菌和冬拟多孔菌的9种游离酚酸总含量远大于粗毛盖菌和火木层孔菌的9种游离酚酸总含量,表明前4种对木质素分解能力较强的菌种获得了较高含量的酚酸;但从9种游离酚酸总的含量上看,与各菌种对木材和木质素的分解百分率不尽相同,初步分析的原因表明在木质素被分解的过程中除了有这9种游离酚酸产生以外,可能还会产生其他的游离酚酸以及苯环二聚体、三聚体和各种寡聚体以及杂环的形式,所有这些苯环结构总体造成了对木质素分解百分率的差异. 对9种酚酸进行分析测试,只构成对木质素分解的一部分,不足以用来解释对木质素的全部分解能力,其他的酚酸和游离酚酸以外的苯环结构还有待进一步研究分析测试;从各种游离酚酸单个含量上看,各种白腐菌的种类和含量都各不相同,表明不同白腐菌对同一木质纤维基质的分解途径、中间降解产物各不相同.另外,未腐朽的木材中本身就含有一些微量的酚酸成分,这些酚酸在生物分解过程中会降解和转化成其他成分, 是否有可能转化成其他种类的酚酸还有待进一步证明.     

The use of the green fluorescent protein as a biomarker for sapstain fungi

To understand wood colonization by sapstain fungi and their potential biocontrol agents, it is necessary to differentiate these organisms directly on their natural substrates. In the present study the feasibility of transforming with the green fluorescent protein (GFP), the sapstain fungus Ophiostoma piceae and a potential biocontrol agent Cartapip^®, an Ophiostoma piliferum albino strain was assessed. Transformants of the two fungal species were screened by polymerase chain reaction and Southern blot analyses. The GFP was expressed in spores, synnemata and mycelia of the transformants grown in artificial media or wood. The growth, pigmentation and wood colonization of the transformants were similar to that of the non‐transformants, suggesting that the presence of the gfp gene had no negative effect on the biology of the transformants. Using fluorescence and confocal microscopy, the GFP‐expressing fungi were easily differentiated from the wild‐type strains and other fungal species in wood, even 4 months after inoculation. The results show that the use of the GFP system is feasible to monitor Ophiostoma fungi in wood.     

木材真菌染色研究现状及发展趋势

木材真菌染色是由于真菌侵染而导致材色改变,包括菌纹线、白腐和染色。木材真菌染色可形成特殊肌理和色泽,改善木材的装饰特性,为木质产品的设计带来多样化的塑造空间。作为一种全新、天然的染色方式,真菌染色技术对于木材的美学价值和综合利用率都有较大提高。目前,分析木材真菌染色机理及染色工艺改进是开发真菌染色木材的关键。菌纹线是由于真菌的种间或种内的对抗形成,染色是由于真菌在细胞外部分泌色素或是伴随真菌自身在木材内部的生长形成。笔者从木材真菌染色机理、染色方法、染色条件、真菌染色木材性能等方面综述了木材真菌染色的研究进展。重点介绍了针对不同表现形式的不同染色方法,并对存在的问题进行了分析,提出了后续研究的方向为采用多种真菌的组合运用、环保色素溶剂的筛选、探寻更多的真菌色相用于色素提取方法染色、结合染料渗透机理改进染色工艺等。