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

Fig. 37 – Line drawings of Cercospora ipomoeae
on Ipomoea obscura. a. Conidiophores
and stromata. b. Conidia. Bars = 50 μm.
(Meeboon 2009).
Phadeng, Mushroom Research Centre, on
leaves of Argyreia henryi Craib (Convolvulaceae),
10 November 2006, Ikumitsu Araki
(CMU 27911); Chiang Mai Province, Chiang
Mai University, Faculty of Agriculture, on
leaves of I. obscura (L.) Ker Gawl. (Convolvulaceae),
21 August 2008, Jamjan Meeboon
(BBH 23558).
Hosts – Argyreia tiliaefolia, Convolvulus
arvensis, Dichondra repens, Hewittia bicolor,
Hewittia sp., Ipomoea acuminata, I. alba, I.
aquatica, I. armata, I. asarifolia, I. batats, I.
biloba, I. bonanox, I. cairica, I. carnea, I.
clarensis, I. coccinea, I. cordofana, I. cymosa, I.
eriocarpa, I. fistulosa, I. forsteri, I. hederacea,
I. hildebrantii, I. indica, I. kentrocarpa, I.
lacumosa, I. leari, I. longicuspis, I. nil, I.
pandurata, I. pes-caprae, pestigridis, I. purpurea,
I. quamoclit, I. ramonii, I. reptans, I.
septaria, I. triloba,I. turpethum, I. villosa,
Jacquemontia tammifolia, Merremia chrysoides,
M. Emarginata, M. Umbellata, Operculina
sp. (Convolvulaceae) (Crous & Braun 2003,
Meeboon et al. 2007c).
Plant Pathology & Quarantine
Distribution – Worldwide, including
American Samoa, Antigua and Barbuda,
Argentina, Australia, Barbados, Brazil, Brunei,
China, Cook Islands, Costa Rica, Cuba, Fiji,
Guam, Hong Kong, India, Indonesia, Italy,
Ivory Coast, Jamaica, Japan, Kenya, Kiribati,
Korea, Malaysia, Marshall Islands, Mauritius,
Myanmar, New Caledonia, New Zealand,
Pakistan, Panama, Papua New Guinea, Puerto
Rico, Samoa, Sierra Leone, Solomon Island,
Sudan, Venezuela, Taiwan, Tanzania, Thailand,
USA, Vanuatu (Crous & Braun 2003, Meeboon
et al. 2007c).
Notes – The first report of C. ipomoeae
on Argyreia henryi from Thailand was made by
Meeboon et al. (2007c). Crous & Braun (2003)
assigned this species to C. apii s.lat.
Literature – Chupp (1954, p. 171).
Cercospora operculinae Mendoza, Phiipp. J.
Sci. 75: 174 (1941).
= Cercospora operculinicola Kamal, in
herb. (IMI 367133).
(= C. apii s. lat.) Fig. 38
Leaf spots 1–6 mm diam., amphigenous,
distinct, circular to subcircular, brown, with
dark margin. Caespituli amphigenous. Stromata
7–55 μm diam., substomatal, small to welldeveloped,
composed of a few globose to
subglobose, brown cells. Conidiophores 64–
127.5 × 3–5 μm, 2–7 in loose fascicles, 2–8septate,
arising from stromata, straight, unbranched,
cylindrical, smooth, brown at the
base, paler toward the apex, plainly geniculate.
Conidiogenous cells integrated, holoblastic,
polyblastic, rarely monoblastic, terminal, sympodially
proliferating. Conidiogenous loci 1–2
μm diam., conspicuous, thickened and darkened.
Conidia 22.5–96 × 3–3.5 μm, solitary,
acicular, sometimes obclavate, straight, hyaline,
6–9-septate, smooth, truncate at the base,
tapering toward a subacute apex, hila 1–2.3 μm
diam., conspicuous, thickened and darkened.
Specimen examined – THAILAND,
Chiang Mai Province, A. Mae Taeng, on leaves
of Operculina turpethum (L.) Silva Manso
(Convolvulaceae), 6 February 2008, Jamjan
Meeboon and Iman Hidayat (BBH 23768).
Hosts – Operculina bufalina, O. riedeliana,
O. turpethum (Convolvulaceae) (Crous
& Braun 2003).
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