Molecular phylogeny of Nectria species associated with dieback and canker diseases in China, with a new species described Author Yang, Qin The Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing 100083, China Author Du, Zhuo The Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing 100083, China Author Liang, Ying-Mei Museum of Beijing Forestry University, Beijing 100083, China Author Tian, Cheng-Ming The Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing 100083, China text Phytotaxa 2018 2018-06-15 356 3 199 214 http://dx.doi.org/10.11646/phytotaxa.356.3.2 journal article 10.11646/phytotaxa.356.3.2 1179-3163 13706646 Nectria pseudotrichia Berk. & M.A. Curtis, J. Acad. Nat. Sci. Philadelphia 2, 2: 289. 1853. FIGURE 6 . Host/distribution :—Pathogen on twigs and branches of Juglans regia , Kadsura longipedunculata , Ulmus pumila . Known from Acacia sp. , Eucalyptus viminalis , Schinus myrtifolia in Argentina ; Litchi chinensis in Australia ; Acer sp. , Albizia julibrissin , Grevillea robusta , Jussiaea peruviana in Florida; Cajanus indicus , Cedrela toona , Cordia macrophylla , Guarea guidonia in Puerto Rico ; Hydrangea sp. , Mallotus sp. , Mucuna sp. in China ; and Cedrela toona in Thailand ( Seifert 1985 , Hirooka et al. 2012 ). Asexual morph on natural substrata :— Synnemata usually erumpent through epidermis, solitary or gregarious, crowded to caespitose, cylindrical-capitate, subulate-capitate, or claviform, erect or nodding, unbranched, medium to slender, distinctly hispid at base to mid-level, young synnemata smooth to granular, soft- textured when fresh, red-brown at base, turning blood-red in KOH, toward base becoming almost black with age, 760–1250 μm in height including stipe, 176–278 μm in width. Ornamental cells cylindrical, straight, curved, sinuous or twisted, arising laterally at more or less right angles, distributed evenly over surface of synnemata or concentrated near base or apex, 5–12 μm in length, 1.5–2.0 μm in width, usually unbranched but occasionally dichotomously branched, aseptate. Conidiophores with sterile hyphae, branching monoverticillate or biverticillate. Conidiogeonus cells enteroblastic, monophialidic, cylindrical to subulate, straight or curved in terminal whorls with sterile hyphae or lateral and terminal, 11.5–34 × 1.2–1.8 μm, collarette not conspicuous. Sterile hyphae mixed with phialides, acicular, straight, or usually curved, unbranched or dichotomously branched, 14–36 × 1.4–2.1 μm, arising from hyphae, often in groups of 1–5, from conidiophores together with phialides. Conidial masses globose, hemispherical or more-or-less discoid, whitish yellow when fresh, drying sienna, 170–255 μm in width. Conidia hyaline, ellipsoidal, obovate or oblong, sometimes slightly curved, non-septate, (4.0–)4.5–7.5(–8.0) × (2.0–)2.5–3.6(–4.1) μm (n = 50), smooth-walled. Sexual morph: Unknown. FIGURE 6. Morphology of Nectria pseudotrichia from Ulmus pumila (BJFC-S1392). A: Host branch. B–D: Synnemata on natural substrata. E: Median section of synnema. F–H: Conidiophores and conidia. I: Conidia. Scale bars: C = 1 mm; D–E = 500 μm; F–I = 20 μm. Cultures :—Colony surface is cottony with aerial mycelium orange, sometimes yellowish brown, with uniform texture; aerial mycelium white to whitish yellow; reverse orange to yellowish brown. Materials examined :— CHINA , Shanxi Province , Taiyuan City , Lingshi County , 36°85′54.86″N, 111°79′20.69″E, alt. 460 m , on twigs and branches of Ulmus pumila , coll. Y . M . Liang, 23 August 2016 ( BJFC-S1392 ; living culture, CFCC 52123 ) ; Jiangxi Province , Shangrao City , 28°52′33.00″N , 118°03′59.00″E , alt. 460 m , on twigs and branches of Kadsura longipedunculata , coll. B . Cao, 1 April 2017 ( BJFC-S1391 ; living culture, CFCC 52122 ) ; Zhejiang Province , Tianmu Mountains , 30°19′18.21″N , 119°26′33.61″E , alt. 332 m , on twigs and branches of Juglans regia , coll. Q . Yang & Z . Du, 20 April 2017 ( BJFC-S1393 ; living culture, CFCC 52124 ) Notes :— Nectria pseudotrichia is a rather common tropical fungus in the genus Nectria . The isolates CFCC 52122, CFCC 52123, and CFCC 52124 were shown to be N. pseudotrichia based on the phylogenetic analysis and their morphological traits. This finding represents a new host plant record for China .