Genus Cercospora in Thailand: Taxonomy and Phylogeny (with a ...

Stromata 19–29 µm diam., small, composed of
a few globose to subglobose, dark brown cells.
Conidiophores 34–85 × 2.5–5 μm, up to 13
in moderately dense fascicles, 1–3-septate,
straight to decumbent, unbranched, light brown
to brown, paler and narrower towards the apex,
plainly geniculate with 1–5 geniculation near
the apex. Conidiogenous cells integrated, terminal,
holoblastic, polyblastic, sympodially
proliferating. Conidiogenous loci 2–3 μm diam.,
conspicuous, thickened and darkened. Conidia
12–67 × 2.5–3.5 μm, 4–7-septate, hyaline,
acicular, obconically truncate at the base, with
acute apex, hila 2–3 μm in diam., thickened
and darkened.
Specimens examined – THAILAND,
Chiang Rai Province, Wiang Pa Pao, on leaves
of Celosia argentea L., 25 November 2005,
Jamjan Meeboon (CMU 27902 ); same locality,
on C. argentea var. cristata (L.) Kuntze, 25
November 2005, Jamjan Meeboon (CMU
27893).
Hosts – Celosia argentea, C. argentea
var. cristata, C. aristata, C. laxa, C. plumosa,
C. trigyna, Celosia spp. (Amaranthaceae)
(Crous & Braun 2003, Meeboon 2009).
Distribution – Bangladesh, Brazil, Brunei,
Cambodia, China, Cuba, India, Indonesia,
Japan, Malaysia, Myanmar, Nigeria, Pakistan,
Papua New Guinea, Sabah, Sri Lanka, Sudan,
Taiwan, Thailand, Uganda, USA, and
Venezuela (Crous & Braun 2003).
Plant Pathology & Quarantine
Notes – Cercospora celosiae on C. argentea
and C. argentea var. cristata was
reported from Thailand by Petcharat &
Kanjanamaneesathian (1989), Sontirat et al.
(1980) and Meeboon (2009).
Cercospora ricinella Sacc. & Berl., Atti Reale
1 st . Ven. Sci. Lett. Art. 6, Ser. 3: 721 (1885).
≡ Cercosporina ricinella (Sacc. & Berl.)
Speg., Anales Mus. Nac. Hist. Nat. Buenos
Aires 20: 429 (1910).
= Cercospora albido-maculans G.
Winter, Hedwigia 24: 202 (1885); also in J.
Mycol. 1: 124 (1885). (Fig. 17)
Leaf spots – 2–9 mm diam., distinct,
amphigenous, circular or subcircular, greyish
brown, with reddish brown margins. Caespituli
amphigenous. Stromata 12–26 μm diam., intraepidermal,
small, composed of globular to
angular, brown to blackish brown cells. Conidiophores
47–125 × 3–5 μm, 5–9 in loose and
divergent fascicles, 1–4-septate, arising from
stromata, erect to decumbent, smooth, pale
yellow to pale brown, unbranched, subcylindrical,
strongly geniculate. Conidiogenous
cells integrated, terminal to intercalary, holoblastic,
polyblastic, sympodially proliferating.
Conidiogenous loci 2.5–3 μm diam., conspicuous,
thickened and darkened. Conidia 29-
168.5 × 2.5–3.5 μm, solitary, narrowly obclavate
to subacicular, 2–12-septate, straight to
curved, hyaline, smooth, base obconically
Fig. 16 – Line drawings of Cercospora celosiae on Celosia argentea. a. Conidiophores and stroma.
b. Conidia. Bars = 50 µm. (Meeboon 2009).
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