15 July 2014, 33(4): Mycosystema ISSN CN /Q 2014 IMCAS, all rights reserved.

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1 菌物学报 15 July 2014, 33(4): Mycosystema ISSN CN /Q 2014 IMCAS, all rights reserved. 研究论文 Research paper DOI: /j.mycosystema Five new species of Scolecobasidium (Hyphomycetes) and a key to species of the genus known from soil in China XU Jun Jie 1, 2Δ ZHANG Yue Li 1, 3, 5Δ WU Yue Ming 1 GENG Yue Hua 1, 4 ZHANG Tian Yu 1* 1 Department of Plant Pathology, Shandong Agricultural University, Tai an, Shandong , China 2 College of Life Sciences, Linyi University, Linyi, Shandong , China 3 Institute of Plant Protection, Shandong Academy of Agricultural Sciences, Jinan, Shandong , China 4 College of Plant Protection, Henan Agricultural University, Zhengzhou, Henan , China 5 Shandong Key Laboratory of Plant Virology, Jinan, Shandong , China Abstract: Five new species of the genus Scolecobasidium: S. acutimum, S. anisomerum, S. curvularioides, S. spheroideum and S. zhejiangense from soil in China are described and illustrated. The relationship of the new taxa with similar species are discussed. Additionally, a key to twenty two Scolecobasidium species known from soil in China is provided. The types (dried cultures) and living cultures studied are deposited in the Herbarium of Shandong Agricultural University: Plant Pathology (HSAUP). The isotypes (dried cultures) are kept in HMAS. Key words: soil fungi, dematiaceous hyphomycetes, taxonomy 齿梗孢属 ( 丝孢纲 )5 个新种及中国土壤中本属真菌已知种检索表 许俊杰 1, 2Δ 张悦丽 1, 3, 5Δ 吴悦明 1 耿月华 1, 4 张天宇 1* 1 山东农业大学植物病理学系山东泰安 临沂大学生命科学学院山东临沂 山东省农业科学院植物保护研究所山东济南 河南农业大学植物保护学院河南郑州 山东省植物病毒重点实验室山东济南 摘要 : 报道 5 个中国土壤中齿梗孢属新种 : 细基齿梗孢 Scolecobasidium acutimum 不等齿梗孢 S. anisomerum Supported by the National Natural Science Foundation of China (NSFC) (No ). Δ Co first author. * Corresponding author. E mail: tyzhang1937@163.com Received: , accepted:

2 778 ISSN CN /Q Mycosystema July 15, 2014 Vol. 33 No. 4 弯孢齿梗孢 S. curvularioides 近球齿梗孢 S. spheroideum 和浙江齿梗孢 S. zhejiangense 对新种与各自相似种的区别进行了讨论 文末附有中国土壤中已知 22 种齿梗孢属真菌的检索表 新种模式标本 ( 干制培养物 ) 与活菌种保藏于山东农业大学植物病理学标本室 (HSAUP), 等模式标本 ( 干制培养物 ) 存放在中国科学院真菌标本馆 (HMAS) 关键词 : 土壤真菌, 暗色丝孢菌, 分类 INTRODUCTION The genus Scolecobasidium was established by Abbott (1927) for two species, S. terrum E.V. Abbot (type) and S. constrictum E.V. Abbot, with features: mycelium septate; conidiophores lateral from mycelium, short, curved, aseptate; conidia rectangular, 1 septate, nearly hyaline to olivaceous brown, solitary from 1 3 short denticles which were born from the sides of conidiophores. Barron & Busch (1962) amended the descriptions of the genus and reported two new species: S. humicola G.L. Barron & L.V. Busch and S. variable G.L. Barron & L.V. Busch. Roy et al. (1962) found other two new species: S. macrosporum R.Y. Roy and S. verruculosum R.Y. Roy, R.S. Dwivedi & R.R. Mishra. The conidia of S. macrosporum were 3 septate. Shearer (1974) mentioned that the brown conidia with 1 3 septa existed in long and narrow denticles at the tops of short conidiophores. Narayan & Kamal (1986) published S. trichoides Narayan & Kamal whose conidia has 7 septa. Up to now Scolecobasidium includes about 50 species (http//www. mycobank. Org), 22 species of which were found from soil in China (Liu & Zhang 2006; Yu et al. 2008; Wu & Zhang 2008; Jiang & Zhang 2008; Pan et al. 2009, 2012). During the course of a survey of dematiaceous hyphomycetes from soil in China, five fungi possessed the typical Scolecobasidium characters but did not match other similar species in this genus were obtained, and are therefore described as new species. Additionally, a key to 22 species of the genus known from soil in China is provided. 1 MATERIALS AND METHODS Five species of Scolecobasidium were collected from soil of four provinces in China. The soil samples were stored in 4 freezer after collection and isolations were carried out within at most two months. The single spore cultures were taken by soil plate method and soil dilution plate method. Morphological comparison of sporulation elements of Scolecobasidium spp. were based on cultures which were grown for 2 weeks on potato dextrose agar (PDA; 200g white potato boiled and filtered, 20g dextrose, 20g agar, 1L distilled water) in petri dishes at ambient room temperature 23 25, under a daily fluorescent light/dark cycle of 12/12h. Microscopic slides were prepared in lactophenol and glycerin solution as mounting fluid. Dimensions of microscopic elements belonging to the holotypes were obtained from the measurements of 50 mature conidia and 30 conidiophores, respectively, using an Olympus microscope (model BX 50), with 100 (oil

3 XU Jun Jie et al. / Five new species of Scolecobasidium (Hyphomycetes) and a key to species of the genus known from soil in China 779 immersion) objectives. 2 TAXONOMIC DESCRIPTIONS Scolecobasidium acutimum J.J. Xu & T.Y. Zhang, sp. nov. Fig. 1 MycoBank MB Etymology: acutimum, referring to the conidial shape (tapering towards the base) of the type. Colonies effuse, hairy, olivaceous brown to dark brown, brown in reverse, growing slowly on PDA reaching a diameter of 1 2.5cm at 25 in 2 weeks. Mycelium partly superficial, partly immersed. Hyphae branched, septate, subhyaline or pale brown, smooth, 1 3μm thick. Conidiophores micronematous, pale brown, smooth, short cylindrical or wedge shaped, often swollen at the tip, simple or sparsely branched, continuous or septate, pale brown, up to 13μm long, 1 2.5μm thick. Conidiogenous cells integrated, polyblastic or monoblastic, intercalary or terminal, determinate or sympodial, short cylindrical or subglobose, Fig. 1 Conidia and conidiophores of Scolecobasidium acutimum J.J. Xu & T.Y. Zhang (ex HSAUPⅡ ; bar=25μm). denticulate, smooth. Conidia acropleurogenous, solitary, ellipsoidal, rounded at the tip, tapering towards the base, pale brown, straight, 1 septate, occasionally constricted at septa, minutely echinulate, μm, av μm, brown in mass. Type: From the city planting plot soil, Longyan( 龙岩 ), Fujian Province, China, 8 Jan. 2004, J.J. Xu, HSAUPⅡ (dried culture on PDA), holotype; HMAS , isotype. Comments: This species somewhat resembles Scolecobasidium pallescens W. Song, J.F. Yu & T.Y. Zhang (Yu et al. 2008), S. chinense H.Q. Pan & T.Y. Zhang (Pan et al. 2012), S. crassihumicola Matsush. (Matsushima 1971) and S. humicola G.L. Barron & L.V. Busch (Domsch et al. 2007). Its conidia are rounded at the tip and tapering at the base, with measurements of μm, av μm, while those of S. pallescens are μm, rounded at two ends. S. chinense differs in having brown colored conidia varied in shape. S. crassihumicola and S. humicola are distinguished by their longer (>10μm) conidia. Scolecobasidium anisomerum Y.L. Zhang & T.Y. Zhang, sp. nov Fig. 2 MycoBank MB Etymology: anisomerum, referring to the unequally 2 celled conidia of the type. Colonies effuse, pilose, greyish brown, brown in reverse, growing slowly on PDA reaching a diam. of 1.5 2cm at 25 in two weeks. Mycelium partly superficial, partly immersed, composed of branched, septate, pale brown, smooth walled hyphae, μm thick. 菌物学报

4 780 ISSN CN /Q Mycosystema July 15, 2014 Vol. 33 No. 4 Fig. 2 The conidia and conidiophores of Scolecobasidium anisomerum Y.L. Zhang & T.Y. Zhang (ex HSAUP ; bar=25μm). Conidiophores arise laterally from superficial hyphae, straight or flexuous, occasionally branched, pale brown, smooth, 0 1 septate, μm long, 1.5 3μm thick. Conidiogenous cells polyblastic or sometimes monoblastic, terminal or intercalary, sympodial, straight or flexuous, occasionally branched, cylindrical, denticulate, smooth, light brown. Conidia solitary, acrogenous and lateral, straight, ovoid, napiformly tapered at the base, rounded at the apex, brown, verruculose, 1 septate, slightly constricted at septa, 5 6.5μm long, basal cells 3 4μm wide, apical cells μm wide. Type: From botanical garden soil, Guilin( 桂林 ), Guangxi Province, China, 1 July 2005, Y.L. Zhang, HSAUPⅡ (dried culture on PDA), holotype; HMAS196256, isotype. Comments: In conidial morphology, the present fungus resembles Scolecobasidium constrictum E.V. Abbott (1927) and S. microspora H.M. Liu & T.Y. Zhang (2006). However, the conidia of S. anisomerum (5 6.5μm in length) are shorter than those of S. constrictum (5 12μm in length), and wider than those of S. microspora (2.5 3μm in width). Besides, the two conidial cells of this new taxon are unequal in size, while those of S. microspora are nearly equal. This fungus as a new taxon is supported by the results of molecular systematic analysis based on ITS and LSU gene fragment sequencing. The type specimen HSAUPⅡ has the ITS fragment of 673bp; the base proportions are: A 23.6%, C 26.3%, G 26%, T 24.1%; the molecular weight is kDa. The LSU fragment is 1 418bp, with molecular weight of kDa, and the base proportions are: A 26%, C 21.5%, G 30.2%, T 22.3%. ITS and LSU gene fragment sequencing shows that in ITS MP system topological structure, HSAUPⅡ is separated as an alone branch; in the LSU MP system topological structure diagram it is also separated as an alone branch, distinguishing this fungus from other species in the genus Scolecobasidium. Scolecobasidium curvularioides J.J. Xu & T.Y. Zhang, sp. nov. Fig. 3 MycoBank MB Etymology: curvularioides, referring to the curved conidia of the type. Colonies effuse, compact, hairy, pale brown to yellowish brown, raised in center, regular in margin, brown to dark brown in reverse, growing slowly on PDA reaching a diameter of 1 2.5cm at 25 in 2 weeks. Mycelium partly superficial, partly immersed. Hyphae branched, septate, pale brown or medium brown, smooth,

5 XU Jun Jie et al. / Five new species of Scolecobasidium (Hyphomycetes) and a key to species of the genus known from soil in China 781 Fig. 3 Conidia and conidiophores of Scolecobasidium curvularioides J.J. Xu & T.Y. Zhang (ex HSAUPⅡ ; bar=25μm). 1 3μm thick, sometimes forming simple mycelial ropes. Conidiophores micronematous, pale brown to medium brown, smooth, cylindrical or clavate, swollen at the tip, simple or sparsely branched, septate or continuous, denticulate, 6 50μm long, μm thick. Conidiogenous cells integrated, polyblastic, intercalary or terminal, determinate or sympodial, cylindrical to clavate, denticulate, smooth, pale brown to yellowish brown. Conidia 2 celled, ellipsoidal, obovoid or rarely turbinate, acropleurogenous, solitary, pale brown, brown in mass, distinctly constricted at septa, usually curved to one side, occasionally straight, rounded at the apex, tapering to the base, short stipitate, the basal cells usually larger than the top cells, μm. Type: From soil under trees, Xiamen( 厦门 ), Gulangyu( 鼓浪屿 ), Fujian Province, China, 8 Jan. 2004, J.J. Xu, HSAUPⅡ (dried culture on PDA), holotype; HMAS196257, isotype. Comments: In conidial morphology, the present fungus resembles Scolecobasidium qinghaiense H.Q. Pan & T.Y. Zhang (2012), S. chinense H.Q. Pan & T.Y. Zhang (Pan et al. 2012) and S. compactum M.B. Ellis (1976). It differs from S. qinghaiense by its conidia usually curved to one side, while the conidia of the latter are usually straight. It differs from S. chinense by the features of that its conidia are distinctly constricted at septa, while the conidia of the latter usually have flat spore body. S. compactum differs in having conidiophores usually in tight clusters and straight and echinulate conidia (Ellis 1976). Scolecobasidium sphaeroideum Y.L. Zhang & T.Y. Zhang, sp. nov. Fig. 4 MycoBank MB Etymology: sphaeroideum, referring to the nearly spherical conidia of the type. Colonies on PDA effuse, pilose, olivaceous brown to dark brown, brown in reverse, growing very slowly reaching a diam. of 1.5 2cm at 25 in 4 weeks. Mycelium partly superficial, partly immersed, composed of branched, septate, pale brown, smooth walled hyphae, 1.5 2μm thick, aerial hyphae developed, forming simple mycelial ropes. Conidiophores arise laterally from superficial hyphae, straight or flexuous, occasionally branched, pale brown, smooth, septate, 22 38μm long, μm thick. Conidiogenous cells integrated, polyblastic or monoblastic, intercalary or terminal, determinate, short cylindrical, denticulate, smooth. Conidia solitary, acrogenous, straight, 菌物学报

6 782 ISSN CN /Q Mycosystema July 15, 2014 Vol. 33 No. 4 broadly ellipsoidal to subglobose, brown, verruculose, 1 septate, μm. Type: From rice field soil, Xiaonanhai( 小南海 ), Chongqing, China, 1 Dec. 2005, Y.L. Zhang, HSAUPⅡ (dried culture on PDA) holotype; HMAS196258, isotype. Comments: The new taxon differs from all the species in the genus Scolecobasidium whose conidia are 2 celled, broadly ellipsoidal to subglobose, and conidial L/W<2. Fig. 4 Conidia and conidiophores of Scolecobasidium sphaeroideum Y.L. Zhang & T.Y. Zhang (ex HSAUPⅡ ; bar=25μm). medium brown, smooth, 1.5 3μm thick. Conidiophores micronematous, pale brown, smooth, short cylindrical or wedge shaped, swollen at the tip, simple or occasionally branched, aseptate, pale brown, denticulate, μm. Conidia acropleurogenous, solitary, ellipsoidal, obovoid or rarely turbinate, pale brown to medium brown in mass, minutely echinulate, 1 septate, μm, av μm. Type: From vegetable plot soil, Zhoushan ( 舟山 ), Shenjiamen( 沈家门 ), Zhejiang Province, China, 8 Jan. 2004, J.J. Xu, HSAUPⅡ (dried culture on PDA), holotype; HMAS196259, isotype. Comments: The new species differs from all the members of Scolecobasidium whose conidia are 2 celled, having the septum approximately positing at the middle of the spore. Its conidia are ellipsoidal, obovoid or rarely turbinate and short (<10μm). Scolecobasidium zhejiangense J.J. Xu & T.Y. Zhang, sp. nov. Fig. 5 MycoBank MB Etymology: zhejiangense, referring to the province where the type specimen were collected. Colonies effuse, compact, hairy, greyish brown to olivaceous brown, raised in center, regular in margin, brown to dark brown in reverse, growing slowly on PDA reaching a diameter of 1 2.5cm at 25 in 2 weeks. Mycelium partly superficial, partly immersed. Hyphae branched, septate, pale brown to Fig. 5 Conidia and conidiophores of Scolecobasidium zhejiangense J.J. Xu & T.Y. Zhang (ex HSAUPⅡ ; bar=25μm).

7 XU Jun Jie et al. / Five new species of Scolecobasidium (Hyphomycetes) and a key to species of the genus known from soil in China 783 Key to species of the genus Scolecobasidium known from soil in China 1. Conidia 1 septate...2 Conidia more than 1 septate Conidial length/width<2...3 Conidial length/width Conidia broadly ellipsoidal to subspherical, verruculose, µm... S. sphaeroideum Conidia ellipsoidal, ovoid to broadly ellipsoidal Conidia unequally 2 celled, top cells smaller than the basal ones, rounded at apex, napiformly tapered at the base, µm... S. anisomerum Conidia 2 celled, two cells approximately equal Conidia tuberculate, 9 11(10) 4 7(5.5)µm... S. tuberculatum Conidia verruculose Conidia μm, flat at septa, ovoid to ellipsoidal...s. microsporum Conidia 6 9(7.5) 3 6(5)μm, distinctly constricted at septa, ellipsoidal... S. verruculosum 7. Conidia Y or T shaped, µm... S. terrum Conidia obovoid, ovoid, ellipsoidal or other shaped Conidia smooth walled...9 Conidia verruculose or echinulate Conidia distinctly constricted at septa...10 Conidia flat or slightly constricted at septa, straight, μm... S. chinense 10. Conidia usually curved to one side, μm... S. curvularioides Conidia straight, μm...S. qinghaiense 11. Conidia distinctly constricted at septa, μm... S. constrictum Conidia flat or slightly constricted at septa Conidia dimorphic: (1) ellipsoidal, rounded at ends, μm; (2) fusiform, μm... S. dendroides Conidia monomorphic Conidial length<10μm...14 Conidial length>10μm Conidia obovoid or ovoid, μm... S. humicola Conidia broadly ovoid to ellipsoidal, μm... S. crassihumicola 15. Conidia ellipsoidal, obovoid or rarely turbinate, μm... S. zhejiangense Conidia uniformly obovoid to ellipsoidal, pale brown Conidia rounded at ends, μm...S. pallescens 菌物学报

8 784 ISSN CN /Q Mycosystema July 15, 2014 Vol. 33 No. 4 Conidia rounded at apex, tapering at the base, (7.5) (2)μm...S. acutimum 17. Conidia ellipsoidal, ovoid to broadly ellipsoidal or broadly ovoid...18 Conidia cylindrical to ellipsoidal, ovoid or obovoid Conidia smooth, mostly 2 celled, 3 celled conidia unequally septate, μm S. laeve Conidia echinulate, 0 3 septate, equally septate, ellipsoidal, μm... S. ellipticum 19. Conidia bacillary, cylindrical or fusiform...20 Conidia ovoid, obovoid to ellipsoidal Conidia bacillary, 3 septate, constricted at septa, μm...S. longisporium Conidia fusiform or cylindrical, not constricted at septa, μm...S. tshawytschae 21. Conidia obovoid, 1 4 septate, μm...S. obovatum Conidia ovoid, obovoid to ellipsoidal, occasionally with longitudinal or oblique septa, 8 21(15) 4 8(5)μm...S. anellii [REFERENCES] Abbott EV, Scolecobasidium, a new genus of soil fungi. Mycologia, 19: Barron GL, Busch LF, Studies on the soil hyphomycetes Scolecobasidium. Canadian Journal of Botany, 40: Domsch KH, Gams W, Anderson TH, Compendium of soil fungi. 2nd edition. IHW Verlag, Eching Ellis MB, More dematiaceous hyphomycetes. CMI, Kew, Surrey, England Jiang YL, Zhang TY, New species of Bipolaris, Scolecobasidium and Torula from soil. Mycotaxon, 107: Liu HM, Zhang TY, Two new species of Scolecobasidium. Mycosystema, 25(3): (in Chinese) Matsushima T, Microfungi of the Solomon Islands and Papua New Guinea. Published by the author, Kobe Narayan P, Kamal, New foliicolous hyphomycetes from India. Canadian Journal of Botany, 64(1): Pan HQ, Xia HB, Zhang TY, The species of Scolecobasidiun from soil in the source areas of Yangtse River and Yellow River. Mycosystema, 31(5): (in Chinese) Pan HQ, Zhang TY, Kong JH, Notes on soil dematiaceous hyphomycetes from the Yellow River source area, China Ⅰ. Mycosystema, 28(1): (in Chinese) Roy RH, Dwivedi RS, Mishra RR, Two new species of Scolecobasidium from soil. Lloidia, 25: Shearer CA, Fungi of the Chesapeake Bay and its tributaries IV. Three new species from the Patuxent River. Mycologia, 66: Wu YM, Zhang TY, Soil dematiaceous hyphomycetes from Hulunbuir and Xilin Gol Steppe, Inner Mongolia, China. Mycosystema, 27(4): (in Chinese) Yu JF, Song W, Zhang TY, Notes on soil dematiaceous hyphomycetes from Mount Taibai and its surrounding area Ⅱ. Mycosystema, 27(4): (in Chinese)