黑粉菌属的聚类分析

本文对我国黑粉菌属(Ustilago)51个样本,选取33个形态学和生物学编码性状进行了类平均法的系统聚类分析。根据聚类分析结果,建议将我国黑粉菌属分为3个表观群(Phenons);茭白黑粉菌目前以放在黑粉菌属内为妥;还认为 Ustilago ocrearum 是 Ustilagokoenigiae 的变种;Ustilago kusanoi 是 Ustilago minima 的变种;Us(?)ilago aoenoe 和 Usti-lago nuda 是两个不同种。     

黑粉菌属某些种的核rDNA ITS2序列分析

本文报道从某些黑粉菌的黑粉孢子粉末中提取核糖体脱氧核酸(rDNA)后,用聚合酶链式反应(PCR)的方法,对其转录间区(ITS2)片断进行了扩增,核苷酸序列测定和分析,其结果表明异形黑粉菌(Ustilago anomala)与其它3种近似黑粉菌,科尔达黑粉菌(U. cordae),柳叶刺黑粉菌(U. bungeana)和网孢黑粉菌(U. reticulata)的rDNA ITS2序列区别很大,在被测定的190个碱基对中,差别达69个位点以上(26.3-36.3%),异形黑粉菌与这三种黑粉菌亲缘关系较远,在中国作者原定名为异形黑粉菌的种与在欧洲取材的科尔达黑粉菌相似程度较高.因此将在中国已报道的异形黑粉菌更正为科尔达黑粉菌,而柳叶刺黑粉菌与科尔达黑粉菌近似程度也较高,将柳叶刺黑粉菌作为科尔达黑粉菌的异名.     

知母上一种新的黑粉菌

本文报告知母上一种新的黑粉菌,定名为知母楔孢黑粉菌。这种黑粉菌的冬孢子萌发方式表明,先菌丝的特征不适宜于用作黑粉菌分为两科的依据。     

黑粉菌属一新种及中国黑粉菌补遗VI

本文描述采自河北小五台山的黑粉菌一新种,即寄生在野青茅(Deyeuxia arundinacea(L.) Beauv)上的野青茅黑粉菌(Ustilago deyeuxiae L. Guo)。此种与网优黑粉菌(Ustilago scrobiculata Liro)近似,但野青茅黑粉菌网纹明显,网眼高。并报道三种黑粉菌中国新记录。1)酢浆草黑粉菌(Ustilago oxalidis Ellis&Tracy)寄生于醉浆草(Oxalis corniculata L.),此种是我国首次在酢浆草科(Oxalidaceae)植物上发现的黑粉菌。2)网状黑粉菌(Ustilago polygoni-alati Thirum. & Pavgi)寄生于尼泊尔萝(Polygonum nepalense Meisn.),作者对此种进行了订正研究。3)臭草条黑粉菌(Urocystis melicae (Lagerheim & Liro) Zundel)寄生于细叶臭草(Melica radula Fr.)。     

中国黑粉菌属和利罗黑粉菌属

黑粉菌属是Roussel 1806年建立的,全世界记载有三百余种,主要寄生于禾本科,是经济作物及牧草的重要致病菌·长期以来,对黑粉菌的邢子使用过各种名称,如厚垣孢子,冬孢子及黑粉孢子等.本文采用黑粉孢子以区别锈菌的冬孢子. 芳’(1979)在《中国真菌总汇》中列出黑粉菌属五十种及一个变型.作者经过显微结构和超显微结构的研究,承认其中二十九种为正确名称,八种及一变型为异名,顶黑粉菌(Ustilago acrearus Berk.)由于错拼而被废弃.埃地黑粉菌(Ustilago emodensis Berk.)被转移至利罗粉菌属(Liroa).另有十一种黑粉菌因缺少标本留待今后订正.自1979年以后,杨信东(1983)增加黑粉菌属二种我国新纪录,K.范基和郭林(1986)描述一新种,四种新纪录.在本文中,作者描述一新种:鸢尾蒜黑粉(Ustilago ixiolirii Guo L) ,孢子堆生在蒴果内,不开裂,黑色,粉末状.黑粉孢子球形,近球形,稀椭圆形, 12.5-21×10-21μm,黑褐色,壁厚1-1.Sμm,纹饰脑状.是迄今生在石蒜科植物上唯一黑粉菌的种,其它几种黑粉菌均属条黑粉菌属.本文增加七种我国新纪录.共计四十九种,寄生于六科四十四属植物,主要是禾本科和蓼科.这仅是黑粉菌属研究的初步报告,在全国范围内大量采集黑粉菌标本后,作者相信会有更多新种和我国新纪录被发现.利罗黑粉菌属(Liroa)是从黑粉菌属(Ustaligo)分出的,此属为单种属.     

孢堆黑粉菌属三个新组合及中国黑粉菌补遗VIII(英)

本文报道3个新组合种和3个中国新记录种。新组合是：广州孢堆黑粉菌[Sporisoriumcantonense（Zundel）L．Guo]香茅粒孢堆黑粉菌[Sporisoriumcymbopogonis-distantis（Ling）L．Guo]和海南孢堆黑粉菌[Sporisoriumhainanae（Zundel）L．Guo]中国新记录种为：中间炭黑粉菌（AnthracoideaintercedensNannfeldt）,戴维斯黑粉菌（UstilagodavisiiLiro）和田中黑粉菌（UstiilagotanakaeS.Ito）。     

玉米黑粉菌实时荧光定量PCR检测方法的建立

目的:建立利用实时荧光定量PCR对玉米黑粉菌[Ustilago maydis(DC.)Corda]快速定量检测的方法。方法:以玉米黑粉菌βactin基因为内参基因,以含有βactin基因的具浓度梯度pMD19 T-Simple质粒为标准品,接种黑粉菌后不同时间点的玉米叶片作为样本用以检验该方法的实用性。结果:建立了利用实时荧光定量PCR对玉米黑粉菌进行定量分析的方法。该方法重复性好、特异性强、灵敏性高,对玉米黑粉菌的最低检出率为19拷贝/反应,可以准确检测经注射接种后1 d的玉米叶片中的黑粉菌量。结论:建立的实时荧光定量PCR方法可用于玉米黑粉菌菌量的检测。     

寸草黑粉菌新种(黑粉菌目)

自中国青海民和发现一种寄生在莎草科白颖苔草Carexduriusculasubsp.rigescens植物上的黑粉菌新种,寸草黑粉菌Ustilagoduriusculae。此种与寄生在禾本科植物上的条形黑粉菌(Ustilagostriiformis)近似,其区别是寄生植物属于不同的科。     

菰黑粉菌科(Yeniaceae)的确认问题

菰黑粉菌科(Yeniaceae)是刘慎谔(1949)根据阎玫玉(1935)对菰黑粉菌(Yenia esculenta) 冬孢子**萌发方式的研究结果而建立的。但是20多年来,似还没有得到有关工作者的承认, 主要是由于黑粉菌冬孢子萌发方式受环境因素的影响很大,性状不太稳定的缘故。 为了确认 此科建立的必要性和合理性,在前人研究的基础上,对菰黑粉菌冬孢子的萌发方式和条件作了 进一步的研究。结果表明：菰黑粉菌冬孢子在形态上和生理上几乎同时成熟,孢子形成后便 可立即大量萌发。冬孢子的存活力较短暂,在室温下10个月完全丧失萌发力。 菰黑粉菌冬孢子在9-33℃下均能萌发,萌发的适温范围为24-30℃,30℃下8小时便 开始萌发。孢子在pH 2.0-11.0均能萌发,以pH3.5-7.0较好,最适pH为4.0-5.0。合 成培养基和植物性煎汁培养基有利于孢子的萌发,在动物性煎汁培养基和缺乏养料的蒸馏水 培养基上萌发较差。冬孢子在完全光照和完全黑暗下均能萌发。孢子萌发时对氧的需要量不 大,纯氧或过量的氧对萌发似有抑制作用。菰黑粉菌这种对萌发条件要求不严格的特性,表明 它具有广泛的适应性和顽强的生命力。这种特性是它在长期历史发展过程中所形成的,也是 长期人工选择和自然选择的结果。对这些生物学性状的了解,为在生产实践上争取茭白的丰 产奠定了理论基础。 温度、光照、氢离子浓度、营养条件和氧的供应,对菰黑粉菌冬孢子的萌发方式有一定的影 响,特别是对孢子原菌丝影响较大。但是对短的无隔担子原菌丝影响却不大,一般都没有引起 形态上的较大改变。刘慎谔(1949)根据这一性状所建立的菰黑粉菌属(Yenia)和菰黑粉菌科 (Yeniaceae),是有一定根据的,似应给予承认。 本文还对黑粉菌目的演化和分科问题进行了讨论。     

新书简讯

中国黑粉菌王云章著科学出版社出版本书是研究黑粉菌的一本专书,描远了130个种、1个变种和1个变型的黑粉菌,它们分属于15个属,分别寄生在13科75属的种子植物上,其中,有“%的种是寄生在禾本科植物上的。本书首先简短地介绍了研究黑粉菌的历史、黑粉菌各属在各科寄主上的分布、菌种概念、系统关系及分类后,以自然分类为系统,详细描述各科、属、种黑粉菌的形态,寄主,模式种产地及其在我国的分布。每种除有学名外,都订有中     

The smut fungi of the world. A survey

After a short historical review, our current knowledge about the smut fungi of the world, their number, classification, occurrence on host plant groups and their relationship to other groups of fungi are presented. Surprising results of the new classification of smut fungi are shown. The estimated number of existing species, expected results and trends in smut fungus taxonomy, the necessity and modalities of the conservation of smut fungi and the preparation of an illustrated world monograph of smut fungi are discussed.     

The a and b loci of Ustilago maydis hybridize with DNA sequences from other smut fungi.

The smut fungi are obligately parasitic during the sexual phase of their life cycle, and the mating-type genes of these fungi play key roles in both sexual development and pathogenicity. Among species of smut fungi it is common to find a bipolar mating system in which one locus with two alternate alleles is believed to control cell fusion and establishment of the infectious cell type. Alternatively, several species have a tetrapolar mating system in which two different genetic loci, one of which has multiple alleles, control fusion and subsequent development of the infection hyphae. Cloned sequences from the a and b mating-type loci of the tetrapolar smut fungus Ustilago maydis were used as hybridization probes to DNAs from 23 different fungal strains, including smut fungi with both tetrapolar and bipolar mating systems. In general, all of the smut fungi hybridized with the mating-type genes from U. maydis, suggesting conservation of the sequences involved in mating interactions. A selection of DNAs from other ascomycete and basidiomycete fungi failed to hybridize with the U. maydis mating-type sequences. Exceptions to this finding include hybridization of DNA from the a1 idiomorph of U. maydis to DNA from one strain of U. violacea and hybridization of both a idiomorphs to DNA from Saccharomyces cerevisiae.     

Smut fungi (Basidiomycota p.p., Ascomycota p.p.) of the world. novelties, selected examples, trends

After defining the meaning of the term 'smut fungus', their current taxonomic classification is presented. There are to date, 1640 'true' species of smut fungi that are classified into 2 phyla, 2 subphyla, 4 classes, 8 orders, 24 families and 90 genera. Recent changes to the classification of the smut fungi have produced some surprises when compared to their traditional classification. The variability of the symptoms produced by the smut fungi on their host plants, and the great morphological diversity of the spores is illustrated by selected pictures. Trends and perspectives in the research of the taxonomy of smut fungi are discussed. On the occasion of the imminent world monograph of smut fungi the necessity for urgent measures ensuring their global conservation is stressed. If present trends of habitat destruction continue, caused in large part by the human population explosion, many of the estimated 4000 to 4500 species of smut fungi become extinct before they are even discovered.     

Anthracoidea maquensis, a new species of smut fungi from China

This paper describes one new species of smut fungi from Gansu Province, Northwestern China, Anthracoidea maquensis on the host plant Kobresia maquensis, an endemic Chinese species, it was compared with the five known species on the host plant section elyna of Kobresia and the differences of each species were given in the key.     

Sympatry and interference of divergent Microbotryum pathogen species

The impact of infectious diseases in natural ecosystems is strongly influenced by the degree of pathogen specialization and by the local assemblies of potential host species. This study investigated anther‐smut disease, caused by fungi in the genus Microbotryum, among natural populations of plants in the Caryophyllaceae. A broad geographic survey focused on sites of the disease on multiple host species in sympatry. Analysis of molecular identities for the pathogens revealed that sympatric disease was most often due to co‐occurrence of distinct, host‐specific anther‐smut fungi, rather than localized cross‐species disease transmission. Flowers from sympatric populations showed that the Microbotryum spores were frequently moved between host species. Experimental inoculations to simulate cross‐species exposure to the pathogens in these plant communities showed that the anther‐smut pathogen was less able to cause disease on its regular host when following exposure of the plants to incompatible pathogens from another host species. These results indicate that multi‐host/multi‐pathogen communities are common in this system and they involve a previously hidden mechanism of interference between Microbotryum fungi, which likely affects both pathogen and host distributions.     

New species and new records of smut fungi from China

This paper deals with six species of smut fungi which were collected in the provinces Yunnan and Gansu in China. Among them, Anthracoidea yunnanensis and Entorrhiza guttiformis are new species. Sporisorium andropogonis-annulati, which is a new combination, Sporisorium montaniensis, Urocystis pseudoanemones, and Ustilago griffithsii are new records for China.     

Ustilago aldabrensis, a new species from Seychelles, and two other smut fungi on Dactyloctenium

A new smut fungus Ustilago aldabrensis on the grass Dactyloctenium ctenoides is described and illustrated from Aldabra Island in the Seychelles archipelago. It is compared with similar species known on the genus Dactyloctenium. A further two smut fungi infecting this host plant genus, U. dactyloctenii-gigantei and U. idonea are discussed. U. dactyloctenii-gigantei is reported for the first time from Nigeria on a new host plant, D. aegyptium. U. idonea is redescribed, and its nomenclature and geographical distribution are clarified. A key to smut fungi infecting species of Dactyloctenium is provided.     

Domestication of maize, sorghum, and sugarcane did not drive the divergence of their smut pathogens

We investigated two alternative hypotheses for the origin of crop pathogen species: that human-mediated agricultural practices drove the divergence of many crop plant pathogen species or that coevolutionary processes in natural populations of the crops' ancestors drove divergence of pathogen species. We distinguished between these two hypotheses by constructing a robust multigene phylogeny and estimating the dates of divergence among four, monophyletic species of smut fungi (Ustilago maydis, U. scitaminea, Sporisorium reilianum, S. sorghi) known to specifically infect maize, sorghum, sugarcane, and their wild ancestors. Without a fossil record for smut fungi, we calibrated the pathogen species' divergence times to their plant host divergence times. Specifically, a calibration date of 10,000 years was employed to test the hypothesis that the fungal species originated at the time of domestication of their current hosts and a calibration date of 50 million years was employed to test the hypothesis that the fungal species originated on wild ancestors of their domesticated hosts. Substitution rates at five protein coding genes were calculated and rates obtained for the 10,000 year calibration date were orders of magnitude faster than those commonly reported for eukaryotes, thus rejecting the hypothesis that these smut pathogen species diverged at the time of domestication. In contrast, substitution rates obtained for the 50 million year calibration were comparable to eukaryotic substitution rates. We used the 50 million year calibration to estimate divergence times of taxa in two datasets, one comprised solely the focal species and one comprised the focal species and additional related taxa. Both datasets indicate that all taxa diverged millions of years ago, strongly supporting the hypothesis that smut species diverged before the time of domestication and modern agriculture. Thus, smut species diverged in the ecological context of natural host plant and fungal populations.     

Spore Liberation and Dispersal in Smut Fungi*

Teliospores are the most important diaspores of smut fungi, albeit not the only ones. The role of basidla, basidiospores, secondary spores, yeast cells, and infected parts of the host for dispersal has often been neglected. Many smut species have soral structures like galls, peridia, and elaters, which cause teliospores to be liberated over prolonged periods. This increases the chance that at least some spores are released under favourable wet climatic conditions and while host plants are susceptible. In this review, the diversity of dispersal units as well as vectors of smut fungi are presented. The importance of timing of diaspore liberation, flexibility in dispersal strategies, and the genetic and evolutionary implications of dispersal strategies of smut fungi are discussed. The general considerations are complemented by examples based on original field and laboratory observations: peridia of Farysia corniculata and certain species of Sporisorium expose the spore mass by hygroscopic movement under wet conditions (hygrochasy) favourable for teliospore germination and infection of a host plant. Basidia with firmly attached basidiospores liberated from spore balls of Doassansiopsis deformans, branched basidiospores of Rhamphospora nymphaeae, needle-shaped basidiospores of species of Entyloma, folded basidiospores of Mycosyrinx cissi, and stellate groups of yeast cells of Trichocintractia utriculicola show enlarged surfaces, which are advantageous for dispersal in water. Galls filled with spore balls of Doassansiopsis limnocharidis and witches' brooms formed by spikelets infected by Cintractia standleyana separate from the host and fall into water where they are dispersed.     

On the Evolutionary History of Uleiella chilensis,a Smut Fungus Parasite of Araucaria araucana in South America: Uleiellales ord. nov. in Ustilaginomycetes

The evolutionary history, divergence times and phylogenetic relationships of Uleiella chilensis (Ustilaginomycotina, smut fungi) associated with Araucaria araucana were analysed. DNA sequences from multiple gene regions and morphology were analysed and compared to other members of the Basidiomycota to determine the phylogenetic placement of smut fungi on gymnosperms. Divergence time estimates indicate that the majority of smut fungal orders diversified during the Triassic–Jurassic period. However, the origin and relationships of several orders remain uncertain. The most recent common ancestor between Uleiella chilensis and Violaceomyces palustris has been dated to the Lower Cretaceous. Comparisons of divergence time estimates between smut fungi and host plants lead to the hypothesis that the early Ustilaginomycotina had a saprobic lifestyle. As there are only two extant species of Araucaria in South America, each hosting a unique Uleiella species, we suggest that either coevolution or a host shift followed by allopatric speciation are the most likely explanations for the current geographic restriction of Uleiella and its low diversity. Phylogenetic and age estimation analyses, ecology, the unusual life-cycle and the peculiar combination of septal and haustorial characteristics support Uleiella chilensis as a distinct lineage among the Ustilaginomycotina. Here, we describe a new ustilaginomycetous order, the Uleiellales to accommodate Uleiella. Within the Ustilaginomycetes, Uleiellales are sister taxon to the Violaceomycetales.