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 Add this item to the list   Septoria convolvuli (Lib.) Desm.
   
Literature:
 
Page number:59 
Remarks (internal):More than 10 different species of Septoria have been recorded on Calystegia and Convolvulus spp. (Convolvulaceae). Of these S. calystegiae Westend. was transferred to the genus Stagonospora (Grove, 1935). According to Jørstad (1965), S. septulata Beach hardly deserves specific rank. The whole complex of Septoria species on Convolvulaceae needs revision. Nevertheless, the Korean collections agree well with the previous records of S. convolvuli (Grove, 1935; Jørstad, 1965; Radulescu et al., 1973; Sameva, 1991; Lu, 1992; Andrianova and Minter, 2001b; Markevi?ius and Treigiene, 2003). Shin (1998) recorded this species on C. soldanella for the first time in Korea and provided a short description with phytopathological notes. Shin and Sameva (2002) described this species and added C. hederacea as new host record to Korea.
The young ostioles have the trace of guard cells of stomata, suggesting that most of the conidiomata are formed at the stomatal cavities.
 
Description type:Non-original description 
Description:Septoria convolvuli (Lib.) Desm.
Ann. Sci. Nat. Bot., ser. II, 17: 108 (1842)

= Sphaeria lichenoides var. convolvulicola DC., F1. Fr. 5-6: 148, 1815.
= Sphaeria gentianaecola var. convolvulicola (DC.) Fr., Syst. Mycol. 2: 531, 1823.
= Depazea convolvulicola (DC.) Berk., Ann. Mag. Nat. Hist. 6: 363, 1841.
= Depazea convolvulicola (DC.) Rabenh., Deut. Krypt.-Fl. 1: 138, 1844.
= Ascochyta convolvuli Lib., Pl. Crypt. Ard., no. 56, 1830.
= Septoria fuscella Berk., in Currey, Trans. Linn. Soc. Lond. 22: 334, 1859.
= Septoria flagellaris Ellis & Everh., Bull. Torrey Bot. Club 10: 97, 1883.
= Rhabdospora flagellaris (Ellis & Everh.) Kuntze, Rev. Generum Plantarum 3: 511, 1898.
= Septoria septulata Beach, Amer. J. Bot. 6: 19, 1919.
Literature: Saccardo (1884, p. 536); Allescher (1901, p. 764); Grove (1935, p. 377); JÀ¸rstad (1965, p. 30); Radulescu et al. (1973, p. 185); Brandenburger (1985, p. 514); Teterevnikova-Babayan (1987, p. 172); Lu (1992, p. 220); Guo et al. (1993, p. 83); Vanev et al. (1997, p. 148); Muthumary (1999, p. 79), Andrianova and Minter (2001b); Bai et al. (2003, p. 200); Markevi?ius and Treigiene (2003, p. 92).
Lesions on the upper leaf surface, scattered to rarely confluent, distinct, circular to subcircular, small to large, 3-10 mm diam., at first appearing grayish brown to yellowish brown, later turning brown to dark brown without distinct border line, finally becoming grayish brown with clear dark brown margin; on the lower leaf surface initially appearing as indistinct discolored lesions, later becoming grayish brown without distinct border line. Conidiomata pycnidial, scattered, occasionally in aggregations (usually 2 pycnidia touched with their walls), epiphyllous, also rarely hypophyllous, dark brown to brown, globose depressed, immersed, unilocular, (65-)80-140 µm diam.; ostiole subcircular to irregular, 25-60 µm wide, surrounded with darker cells. Conidia filiform, substraight to slightly curved, occasionally sickle-shaped or sigmoid, obconically subtruncate at the basal end, subacute to subobtuse at the distal end, becoming narrower towards the apex, eguttulate, granulate, hyaline to subhyaline, 28-68 x (1.5-)2-2.5 µm, (2-)3-5(-7)-septate, septa more or less distinct.
Habitat: On living leaves of Calystegia hederacea Wall. and Calystegia soldanella Roem. & Schult. - (Convolvulaceae).
Distribution: Circumglobal where the host plants are growing including Korea.
Disease: The Septoria leaf spot on Calystegia spp. seems to be very common in Korea. The circular lesions on the upper leaf surface are dotted with numerous black conidiomata in the later stage of disease development, which are clearly seen under naked eye. By the help of a simple lens we can see the conidial tendrils protruding from the ostioles of conidiomata.
Development of Septoria convolvuli in infected plants may result in withering and thus conidiomata are found within nearly dead leaves. The initial lesions caused by this fungus are devoid of conidiomata. This fungus is a potential agents for biocontrol of the weed, Convolvulus arvensis (Sedlar et al., 1983).
Since the lesions are generally not large and scattered on the leaves, the Korean name of the disease is suggested as 'Jeom-muni-byong', which means literally 'small and scattered-lesion-disease'.
 
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