柴达木盆地中西部土壤中暗色丝孢菌群落多样性分析

从柴达木盆地中西部采集土样59份,涵盖的生态类型有:沙漠、戈壁、湿地、小镇-绿洲等。分离获得暗色丝孢菌108株,经鉴定分属于15属。利用种群优势度、Shannon-Wiener多样性指数、物种均匀度、生态位宽度四项指数,对柴达木盆地中西部不同生境土壤中的有关暗色丝孢菌物种(属级)进行物种多样性分析。结果表明,该地区土壤中暗色丝孢菌的物种优势度存在明显差异:沙漠生境中,链格孢属Alternaria和细基格孢属Ulocladium真菌优势度较高;戈壁生境中,单格孢属Monodictys真菌的优势度最高;湿地和小镇-绿洲生境中,则分别以瓶霉属Phialophora和枝孢属Cladosporium真菌占优势。在小镇-绿洲生境中,土壤暗色丝孢菌的Shannon-Wiener多样性指数最高,均匀度较低;而在沙漠和戈壁生境中多样性指数明显较低,而物种的均匀度较高。在上述四类生境中,链格孢属Alternaria和细基格孢属Ulocladium真菌具有较宽的生态位,为广适性物种;而平脐蠕孢属Bipolaris、卷旋孢属Cirrenaria、弯孢属Curvularia、矛束霉属Doratomyces、粘束孢属Graphium、漆斑霉属Myrothecium、齿梗孢属Scolecobasidium、帚霉属Scopulariopsis、节隔孢属Scytalidium和葡萄穂霉属Stachybotrys10个属真菌的生态位较窄,为狭适性物种。     

黄山大型真菌的物种多样性

安徽黄山属于黄山-怀玉山生物多样性保护优先区域,孕育了极为丰富的生物资源。为了解该区的大型真菌物种多样性,2018-2020年对该区的大型真菌展开了野外调查和标本采集,通过分子生物学方法及子实体形态特征检索比较对获得的标本进行鉴定,并对该区的物种组成、属级地理区系成分、经济真菌和特有成分等进行了统计分析。该地区共发现大型真菌421种,隶属于9纲19目72科200属,其中包含食用菌68种,药用菌31种,毒菌39种,特有种66种。优势科有牛肝菌科Boletaceae、鹅膏科Amanitaceae、红菇科Russulaceae、多孔菌科Polyporaceae、蘑菇科Agaricaceae、小皮伞科Marasmiaceae、光茸菌科Omphalotaceae、球盖菇科Strophariaceae、粉褶菌科Entolomataceae和口蘑科Tricholomataceae 10科,优势属为鹅膏属Amanita、乳菇属Lactarius、蘑菇属Agaricus、金牛肝菌属Aureoboletus、红菇属Russula、粉褶菌属Entoloma、小皮伞属Marasmius、小菇属Mycena、裸脚伞属Gymnopus、粉孢牛肝菌属Tylopilus、栓孔菌属Trametes、丝膜菌属Cortinarius、灵芝属Ganoderma和多汁乳菇属Lactifluus 14属。对黄山大型真菌属级地理成分分析发现该区大型真菌的区系地理成分可分为9类,主要以世界广布成分为主(66.5%),其次是北温带成分(15.5%)和泛热带成分(10.5%)。本研究表明黄山的大型真菌具有丰富的物种多样性,其中食用菌资源较为丰富,主要为世界广布成分,同时也具有较高的特异性。     

大小兴安岭针叶树倒木上木腐真菌的物种多样性

木腐真菌在森林生态系统中具有丰富的物种多样性, 并在倒木的降解过程中发挥重要的生态功能。针叶树是大小兴安岭森林生态系统的优势树种, 因此研究针叶树倒木木腐真菌物种多样性和影响其物种分布的相关环境因子有助于揭示大小兴安岭森林生态系统物质循环的机理。本研究收集了近16年对大小兴安岭地区冷杉属(Abies)、落叶松属(Larix)、云杉属(Picea)和松属(Pinus) 4类针叶树倒木上1,561份木腐真菌标本的采集信息, 统计了物种种类及其腐朽类型, 并选取具有代表性的地点开展木腐真菌群落多样性及其与环境因子的相关性分析。结果显示, 大小兴安岭针叶树倒木木腐真菌有166种, 隶属于70属, 其中白腐真菌有111种, 占所有种类的66.9%, 褐腐真菌为55种, 占所有种类的33.1%。在4类针叶树倒木上均能生长的真菌种类有19种, 占所有种类的11.5%, 其中柔丝干酪孔菌(Oligoporus sericeomollis)是各类倒木上木腐真菌群落中的优势种。大兴安岭地区落叶松属为优势寄主, 其倒木上生长的木腐真菌种类数和个体数在4类倒木中均为最高; 而小兴安岭地区松属倒木上木腐真菌种类数和个体数比其他3类倒木高, 是该地区的优势寄主。对6个代表性地区木腐真菌群落的研究显示, 有11种真菌在6个地区均有分布, 小兴安岭地区木腐真菌多样性普遍高于大兴安岭地区; 聚类分析显示树种比地理位置对木腐真菌物种分布的影响更大。     

宁夏境内腾格里沙漠固沙植物根际土壤真菌多样性研究

从宁夏境内腾格里沙漠不同生境固沙植物根际采集土样108份,共分离得到257株真菌分属于26属,其中青霉属Penicillium、曲霉属Aspergillus、镰刀菌属Fusarium、链格孢属Alternaria、茎点霉属Phoma、毛霉属Mucor、木霉属Trichoderma和丛梗孢属Monilia是固沙植物根际土壤中普遍存在的真菌种群。多样性分析结果表明,沙漠区真菌物种丰富度、Shannon-Wiener多样性指数和Pielou均匀度最高,分别为16、2.5893和0.9339;而草原区物种丰富度、Shannon-Wiener多样性指数和Pielou均匀度最低,分别为14、2.0891和0.7961。Jaccard相似性研究表明,宁夏境内腾格里沙漠地区4个生境固沙植物根际土壤真菌种群相似性为中等不相似。半荒漠区与封育区相似性最高,草原区与沙漠区相似性最低。典范对应分析(CCA)可知,土壤真菌的种类和数量与土壤性状变化密切相关。9个土壤性状中,氮含量和钾含量是根际真菌群落变化的最主要影响因子。     

大小兴安岭地区红菇属物种多样性及其地理成分

红菇属(Russula)真菌广泛分布于世界各地并与多种植物根系共生形成外生菌根, 对于森林生态系统的多样性维持与群落构建具有重要的作用。我国东北大小兴安岭地区是欧亚和美洲北温带地区生物群落交流的关键地区之一, 但该地区有关外生菌根真菌的区系研究较少。本研究对采自大小兴安岭的96份红菇标本进行了形态学鉴定和ITS序列分析, 通过结合世界范围内红菇属代表性物种(146个种)的ITS序列构建了红菇属系统发育图谱。结果表明, 大小兴安岭地区红菇属有46个分类单元, 其中包括37个种和9个未定种。对大小兴安岭地区37种红菇的地理成分分析表明, 北温带分布成分有13种、温带-热带共有成分8种、欧亚成分9种、世界广布成分7种。本研究表明大小兴安岭地区的红菇具有丰富的物种多样性, 而且具有明显的北温带区系特征, 同时也具有一定的区域特殊性。     

不同生境黑果枸杞根际与非根际土壤微生物群落多样性

研究典型生境黑果枸杞根际与非根际土壤微生物群落多样性及其与土壤理化性质间的关系,为进一步研究黑果枸杞抗逆性提供理论数据。采集新疆精河县艾比湖地区(EB)盐碱地、乌苏市(WS)路旁荒地、五家渠市(WQ)人工林带的黑果枸杞根际与非根际土壤,利用Illumina-MiSeq高通量测序技术分析细菌和真菌群落组成和多样性。结果表明:根际土壤细菌多样性高于非根际土壤(WQ除外),而根际真菌多样性低于非根际土壤。WQ非根际土壤细菌和真菌多样性均高于EB和WS;根际细菌多样性排序为EBWSWQ,根际真菌多样性排序为WSEBWQ。根际土壤优势细菌门依次是变形菌门、拟杆菌门、放线菌门、酸杆菌门,真菌优势门为子囊菌门、担子菌门。根际土壤细菌变形菌门、拟杆菌门、酸杆菌门的相对丰度高于非根际土壤,而厚壁菌在根际土壤中的丰度显著降低,真菌优势门丰度在根际土和非根际土中的变化趋势因地区而异; Haliea、Gp10、Pelagibius、Microbulbifer、假单胞菌属、Thioprofundum、Deferrisoma是根际土壤细菌优势属;多孢子菌属、支顶孢属、Corollospora、Cochlonema是根际真菌优势属。细菌、真菌优势类群(门、属)的组成以及丰富度存在地区间差异,厚壁菌门在EB地区的丰富度显著高于含盐量较低的WS、WQ;盐碱生境EB中根际土壤嗜盐细菌的丰度高于非盐碱生境(WQ、WS),如盐单胞菌属、动性球菌属、Geminicoccu、Pelagibius、Gracilimonas、Salinimicrobium等。小囊菌属是EB根际真菌的最优势属,Melanoleuca是WQ和WS的最优势属,地孔菌属、Xenobotrytis、Brachyconidiellopsis、多孢子菌属等在EB根际土壤中的丰度显著高于WQ和WS。非盐碱生境(WS和WQ)的微生物群落之间的相似性较高,并且高于与盐碱环境(EB)之间的相似性,表明土壤含盐量对微生物群落组成丰度具有重要的影响。     

不同生境下川麦冬根围土壤丛枝菌根真菌多样性北大核心CSCD

采用高通量(Illumina Miseq)测序技术对栽培和野生2种生境下川麦冬根围的丛枝菌根(AM)真菌多样性和群落结构进行测定,并结合土壤理化因子进行相关性分析,以明确两种生境下川麦冬根围土壤AM真菌多样性和优势群落的分布特点,探讨AM真菌群落分布差异的驱动因子,为AM真菌应用于麦冬生产提供理论依据和技术支持。结果表明:(1)不同生境下川麦冬根围土壤中共鉴定出AM真菌3属10种,其中野生川麦冬根围土壤鉴定出的AM真菌3属7种,分别隶属于无梗囊霉属(Acaulospora)、多孢囊霉属(Diversispora)和球囊霉属(Glomus),而栽培环境下鉴定出AM真菌1属6种,隶属于球囊霉属。2个生境优势属均为球囊霉属。(2)不同生境下川麦冬根围AM真菌之间存在显著差异,野生生境下川麦冬根围土壤AM真菌多样性指数ACE和Shannon均显著高于人工栽培生境,而Simpson指数则相反。(3)相关性分析表明,AM真菌多样性指数及群落组成结构均与土壤理化因子存在相关性,其中全钾(TK)、全磷(TP)、全氮(TN)对AM真菌多样性指数和群落结构组成均存在显著影响。研究认为,不同生境下川麦冬根围AM真菌群落存在显著差异,球囊霉属为川麦冬互利共生的关键属,TK、TP、TN是不同生境川麦冬根围AM真菌群落差异的主要驱动因子。     

大别山、仙居县和溧水区大型真菌多样性

大型真菌具有重要的经济价值和生态意义,是生态系统不可缺少的重要组成部分。本研究于2018年7月-10月和2019年7月-10月采用踏查法对大别山鹞落坪自然保护区和天堂寨自然保护区、仙居县和溧水区的大型真菌多样性进行调查,共采集到600多份样本,结合形态特征和分子进行物种鉴定,参考大型真菌书籍进行鉴定。结果表明：大别山研究区共鉴定得到大型真菌84种,隶属5纲11目27科56属;仙居县研究区大型真菌共计87种,隶属6纲10目25科56属;溧水研究区大型真菌79种,隶属5纲10目22科38属。多孔菌科（Polyporaceae）和口蘑科（Tricholomataceae）是三个研究区的共有优势科。α-多样性指数分析得出,在不同的生境下,多样性是溧水研究区>仙居县研究区>大别山研究区。研究结果表明,大型真菌物种的丰度与海拔和纬度呈负相关,三个研究区的大型真菌物种不仅有一些北温带特征,也有一些泛热带成分,世界分布属和北温带分布属占当地属总数的大部分。     

云南哀牢山地区种子植物区系研究

依据采集的4 000余份标本及馆藏标本的整理和鉴定,云南哀牢山地区有野生种子植物199科945属2 238种215变种(亚种).植物种类十分丰富,是云南植物多样性最为丰富的地区之一.种子植物区系总体上是亚热带性质,其热带科占70.47%,热带属占63.89%,热带成分虽多于温带成份,但相当数量温带成分的存在反映了该区系具有从热带向温带的过渡性质.该植物区系缺少典型热带成分,但具有不少东亚特征科属.因此,该植物区系在区划上仍属于东亚区中国-喜马拉雅植物亚区,云南高原地区,属于东亚植物区系的一部分.     

真菌系统学大趋势：越来越多的分类单元

分子生物学技术与真菌系统学的有机融合,为真菌分类和系统发育研究带来了革命性的变化。最近20年来,真菌学家们建立了大量的新目、新科、新属和新种,掀开了真菌多样性及其起源进化研究的新纪元,但很多重要的系统发育问题仍没有解决,特别是大量目间、科间的亲缘关系并不清楚。细分是真菌系统学的主流趋势,野生食用菌和毒蘑菇的分类也是如此,近年涌现了越来越多的新分类单元,如在2010-2019年的10年间,中国发表大型真菌（含地衣）新种1 240余个。本专刊收载的15篇论文是对我国野生食用菌和毒蘑菇研究工作的部分总结,对真菌资源利用、毒蘑菇中毒预防与治疗具有较重要的科学意义和应用价值。     

Further connections between the benthic marine algal floras of the northern Arabian Sea and Japan

Identifications made on some recent collections of benthic marine algae from the Sultanate of Oman, northern Arabian Sea, have revealed several new records for this region. A total of eight species, representing five species of Rhodophyceae, two species of Phaeophyceae, and a single species each of Chlorophyceae, are newly reported for Oman. Of particular interest is the fact that these species represent new records for the Indian Ocean, some of which had previously been known from Japan and environs.     

Regional specialization of Sarcodes sanguinea (Ericaceae) on a single fungal symbiont from the Rhizopogon ellenae (Rhizopogonaceae) species complex

We have sampled the mycorrhizal roots of 76 snow plants (Sarcodes sanguinea, Monotropoideae, Ericaceae) in two areas of the Sierra Nevada of California that are ～180 km apart. To identify the fungal symbionts associated with these plants, we first analyzed restriction fragment length polymorphisms (RFLPs) of the internal transcribed spacer region (ITS) of the fungal nuclear ribosomal repeat. Fungal ITS-RFLPs were successfully produced from 57 of the 76 plants sampled, and all symbionts shared the same DNA fragment pattern. The morphology of S. sanguinea mycorrhizae was consistent with that expected from a Rhizopogon species in section Amylopogon. To confirm and refine this identification, a total of six fungal ITS sequences were determined from S. sanguinea mycorrhizae. These sequences were analyzed together with eight existing and eight newly determined ITS sequences from Rhizopogon section Amylopogon. The newly determined sequences include an ITS sequence from the fungal symbiont of pine drops (Pterospora andromedea, Monotropoideae, Ericaceae), a plant that was previously reported to be exclusively associated with the Rhizopogon subcaerulescens group. When these sequences were analyzed together, the Sarcodes symbionts grouped tightly with several collections of R. ellenae including the holotype, one collection of R. idahoensis, and one collection of R. semireticulatus. A different lineage comprised collections of R. subgelatinosus, R. subcaerulescens, another collection of R. semireticulatus, and the Pterospora symbiont. We conclude that S. sanguinea associates exclusively with a single species in the R. ellenae species complex throughout our sampling range. These results indicate a much higher level of specificity in S. sanguinea than was previously reported and confirm the emerging pattern that nonphotosynthetic, monotropoid plants generally associate very specifically with a narrow range of ectomycorrhizal fungi.     

Fungal diversity on submerged wood in a tropical stream and an artificial lake

Two collections of submerged wood were made from the Mushroom Research Centre in northern Thailand. One collection comprising 100 samples was made from an artificial lake, which had been made by damming a stream running through a secondary forest. The other collection comprising 90 samples was made from an adjacent non dammed shallow stream running through a similar forest. A total of 68 fungal taxa were recorded during the study and the Shannon–Weiner index (H′) was applied to evaluate the diversities of freshwater fungi. Sørensen’s index (S′) was calculated to evaluate the similarity of different fungal communities. The variation of freshwater fungi on submerged wood between lentic and lotic habitat is discussed and compared with previous studies. A dramatic decrease in species richness and diversity, with significantly changed species composition were observed in the artificial lake as compared to the non dammed stream.     

Radioactive caesium in British mushrooms

Summary

Thirty-four different taxa of larger fungi have been analysed for their content of caesium 137 over a 3 year period. The majority of the material has been collected from various sites in Central Scotland; 38% of the collections were from North Wales and Merseyside. Comparison has been made between the same species from different sites and different species from the same site. It has also been possible to analyse the same species from the same plot on two consecutive years. The levels of caesium 137 in the fungal species analysed were extremely low when compared with their counterparts in Central Europe and it is concluded that the Chernobyl incident had little effect on the accumulation by these fungi of this radionuclide. There is no evidence that edible species accumulate caesium 137 at levels considered to be dangerous for consumption.     

A new species of Castilleja (Orobanchaceae) from the central Sierra Madre Occidental, Mexico, and an annotated key to the Castilleja species of that region

Castilleja holmgrenii is described from several collections made in the Sierra Madre Occidental in southeast Sinaloa and adjacent southwest Durango, Mexico. The new species is a member of subgenus and sectionCastilleja. This apparently rare species is presently known from two small, geographically restricted populations. Also provided are a list of theCastilleja species of this region with notes on their status and distribution, a key for their identification, and nomenclatural and taxonomic notes concerning some of the species.     

Ectomycorrhizas and putative ectomycorrhizal fungi of Shorea leprosula Miq. (Dipterocarpaceae)

 The ectomycorrhizas of Shorea leprosula Miq. are described and their putative fungal associates discussed. Of the 24 ectomycorrhizal types reported from seedlings, wildlings and 20-year-old trees of Shorea leprosula, 20 were associated with the Basidiomycotina, two with the Ascomycotina and two with either members of the Ascomycotina or the Russulaceae. The dominant group of fungi associated with Shorea leprosula ectomycorrhizas were members of the Russulaceae. This was confirmed by collections of fungal fruiting bodies made under adult Shorea leprosula trees in various parts of Peninsular Malaysia over a period of 3 years. Of the 28 species of putative ectomycorrhizal fungi collected, 15 were members of the Russulaceae. Accepted: 26 March 1997     

Accurate delimitation of Phanerochaete chrysosporium and Phanerochaete sordida by specific PCR primers and cultural approach

White rot fungi, Phanerochaete chrysosporium and Phanerochaete sordida, have been mostly studied in a variety of industrial processes like biopulping and pulp bleaching as well as in bioremediation. Whereas P. sordida is widely distributed in the North Temperate Zone, P. chrysosporium is reported in the restricted area and hundreds of reports have been described from a few strains of P. chrysosporium, which are deposited at various fungal collections in the world. The isolates of two species are not easily discriminated because of their morphological and molecular similarity. Through the ITS sequence analyses, a region containing substantial genetic variation between the two species was identified. PCR amplification using two specific primers was successfully used to differentiate P. chrysosporium from P. sordida. These results were supported by cultural studies. The growth rates at 37 degrees C on PDA, MEA, and Cza and the microscopic features of conidia on PDA and YMA were also very useful to differentiate those two species.     

An ecological classification of European Drosophila species

Summary The associations shown between species of Drosophila collected in three European countries are analysed using a clustering method. The resulting dendrograms are combined to give a plan of associations shown by all three surveys. These general groupings are interpreted in the light of what is known about Drosophila breeding sites.One ecological group, the fungal breeding species are examined in detail and their pattern of geographical associations investigated. The three most abundant species in collections, D. transversa, D. phalerata and D. cameraria appear to replace one another in a north-south direction in western Europe. It is suggested that ecologically marginal areas may be defined using the frequency of a species within its ecological group.     

High-throughput culturing of fungi from plant litter by a dilution-to-extinction technique

High-throughput bacterial cultivation has improved the recovery of slow-growing and previously uncultured bacteria. The most robust high-throughput methods are based on techniques of 'dilution to extinction' or 'extinction culturing'. The low-density partitioning of CFUs in tubes or microwells exploits the fact that the number of culturable species typically increases as inoculum density decreases. Bacterial high-throughput culturing methods were adapted to fungi to generate large numbers of fungal extinction cultures. The efficiency of extinction culturing was assessed by comparing it with particle filtration and automated plate-streaking. Equal volumes of particle suspension from five litter collections of the New Zealand forest tree Elaeocarpus dentatus were compared. Dilute particle suspensions of litter were pipetted into 48-well tissue culture plates containing 1 mL of agar medium per well. Particle volumes from the same samples were applied to continuous agar surfaces in Omnitray plates by automated streaking, and fungal diversity and richness were measured. The spectrum of isolates was assessed by microscopy and sequencing of the ITS or 28S region of the rRNA gene. Estimates of species diversity between the two methods were comparable, but extinction culturing increased species richness. Compared with plating methods using continuous surfaces, extinction culturing distributes fungal propagules over partitioned surfaces. Intercolony interactions are reduced, permitting longer incubation times, and colony initiation and recovery improved. Effort to evaluate and recover colonies from fungal isolation plates was substantially reduced.