Liberato José R, Barreto Robert W, Niinomi Seiko, Takamatsu Susumu
Departamento de Fitopatologia, Universidade Federal de Viçosa 36571-000, Viçosa, MG, Brazil.
Mycol Res. 2006 May;110(Pt 5):567-74. doi: 10.1016/j.mycres.2006.01.012. Epub 2006 Apr 17.
The powdery mildew monotypic genus Queirozia was reduced to a synonym of Pleochaeta in 1982. Now, a re-examination of the type material of Queirozia and of two other specimens showed that Queirozia turbinata has a very distinct combination of characters that do not allow its placement within Pleochaeta. It has forked special aerial hyphae, subclavate and predominantly lemon-shaped conidia, and both conidiophores and conidia varying from greyish to yellowish brown (a feature that appears to be unique for this fungus within the Erysiphales). This may represent the first dematiaceous anamorphic powdery mildew known to science. This fungus also has hemiendophytic mycelium, a character considered almost exclusive to the tribe Phyllactinieae. The outer wall surface pattern of wrinkled and turgid conidia of Q. turbinata as observed under the SEM is different from those presented in the literature for this tribe. Molecular analysis showed that Q. turbinata belongs to the tribe Phyllactinieae and is phylogenetic closer to Pleochaeta than to Leveillula or Phyllactinia. It is therefore acknowledged that Queirozia is closely related to Pleocheta but too distinct morphologically from this genus to be accepted as a synonym. Emended descriptions of Queirozia and Q. turbinata are presented.
粉状白粉菌单型属奎罗斯白粉菌（Queirozia）在1982年被归为叉丝单囊壳属（Pleochaeta）的异名。如今，对奎罗斯白粉菌的模式标本以及另外两份标本的重新检查表明，陀螺状奎罗斯白粉菌（Queirozia turbinata）具有非常独特的特征组合，使其无法归入叉丝单囊壳属。它有分叉的特殊气生菌丝、近棍棒形且主要呈柠檬形的分生孢子，分生孢子梗和分生孢子的颜色从浅灰色到黄褐色不等（这一特征在白粉菌目中似乎是该真菌独有的）。这可能是科学上已知最早的暗孢型无性态白粉菌。这种真菌还具有半内生菌丝体，这一特征几乎是叶生单囊壳族（Phyllactinieae）所独有的。扫描电子显微镜下观察到的陀螺状奎罗斯白粉菌皱缩且肿胀的分生孢子外壁表面模式与该族文献中描述的不同。分子分析表明，陀螺状奎罗斯白粉菌属于叶生单囊壳族，在系统发育上与叉丝单囊壳属的关系比与离壁壳属（Leveillula）或球针壳属（Phyllactinia）更近。因此，可以确认奎罗斯白粉菌与叉丝单囊壳属关系密切，但在形态上与该属差异明显，不能被视为异名。本文给出了奎罗斯白粉菌属和陀螺状奎罗斯白粉菌的修订描述。
