Queirozia turbinata (Phyllactinieae, Erysiphaceae): a powdery mildew with a dematiaceous anamorph

Abstract

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.

Molecular phylogenetic analyses reveal a close evolutionary relationship between <I>Podosphaera</I> (<I>Erysiphales</I>: <I>Erysiphaceae</I>) and its rosaceous hosts

“…The Erysiphaceae is a group of obligate biotrophic fungi that cause powdery mildew disease on about 1 × 10 4 angiosperm species (Amano 1986), and it consists of 16 genera and approximately 650 species (Braun & Takamatsu 2000, Braun et al 2002, Takamatsu et al 2005a, b, Liberato et al 2006). The host range of this fungal group is strictly confined to angiosperms and the fungi have never been reported to infect ferns or gymnosperms (Amano 1986).…”

Molecular phylogeny and evolution of subsection Magnicellulatae (Erysiphaceae: Podosphaera) with special reference to host plants

“…650 species (Braun and Takamatsu 2000;Braun et al 2002;Takamatsu et al 2005a, b;Liberato et al 2006). The host range of this fungal group is strictly restricted to angiosperms, and the fungi have never been reported to infect ferns or gymnosperms (Amano 1986).…”

Características e importância econômica da fruticultura 2

“…Os gêneros Sphaerotheca e Podosphaera também foram combinados em único gênero, 'Podosphaera'TAKAMATSU, 2000).Análises filogenéticas moleculares revelaram que Uncinula septata e U. curvispora, espécies que causam oídio em plantas fagáceas e endêmicas do leste da Ásia, se separaram de outros oídios em um estágio inicial da evolução e, portanto, um novo gênero, Parauncinula, foi proposto para essas duas espécies(TAKAMATSU et al, 2005). A espécie Uncinula forestalis também separou de outros oídios em estágio inicial de evolução e o gênero Caespitotheca, foi proposto para essa espécie(TAKAMATSU et al, 2005).A espécie Pleochaeta turbinata foi proposta para o gênero Queirozia, pois se distinguia claramente de outros oídios(LIBERATO et al, 2006). Oidium phyllanthi passou a fazer parte do novo gênero, Microidium(TO-ANUN et al, 2005).…”