日 植 病 報 64: 38-41 (1998) 短 報

Ann. Phytopathol. Soc. Jpn. 64: 38-41 (1998) Phytopathological Note

Anthracnose of Liriope platyphylla Caused by Glomerella cingulata

Takao KOBAYASHI* and Chung-Ho CHEN*,**

Key words: Anthracnose, Glomerella cingulata, Liriope platyphylla.

In May of 1995, a severe leaf blight of Liriope platy- appeared 3-4 days after inoculation and soft rot pro- phylla Wang et Tang was found at Toride, Ibaraki gressed rapidly. Many conidial masses were produced on Prefecture. On leaf spots and blighted areas, numerous the infected skin. fruit-bodies of Glomerella and were rec- Germination of (Fig. 1) Conidia began ognized. Isolates from a single and a conidium to germinate between 2 to 4 hr on water agar (WA) at produced similar colonies having the same size and 25℃, and ca. 80% of the conidia germinated after 10hr. shape of conidia. Conidia were elliptic to cylindric and They germinated between 10 and 35℃, but not at 5 and distinctly different from the falcate conidia of Colletotri- 40℃, within 24hr on WA. Optimum temperature was chum dematium (Persoon: Fries) Grove, a hitherto 25℃. Conidia died after 20min at 40℃. known anthracnose on Liriope (Iwata 1941)6). Growth of mycelial colony (Figs. 2-4) Fungal Therefore, etiological studies of Glomerella on Liriope colonies grew well on Richards' solution agar and potato were carried out. Summarized results were previously sucrose agar, but poorly on Saito's soy agar, after 7 days reported1). at 25℃, among the tested agar media (Fig. 2). Best Symptoms and signs (Plate 1-A, B) Small brown colony growth was observed at 30℃ after 7 days on PSA spots, 1-2mm in diam., developed on leaf blades in late (Fig. 3a). The fungus grew well at pHs 5 to 9, but quite autumn. During winter, they increased gradually in poorly at pH 3 and 4 (Fig. 3b). Fructose, but not sucrose, number and size. In spring, spots rapidly enlarged, was a good carbon source for colony growth on Hop- coalescing into a severe grayish brown leaf blight with kins' solution agar at 25℃ (Fig. 4a). Good growth of a dark brown border. Numerous black points of perithe- mycelial colony was recorded on Hopkins'solution agar cia and pinkish sticky masses of acervuli were produced contained KNO3 or NaNO3, whereas the fungus could on the leaf spots and blighted areas. not utilize (NH4)2SO4 as a nitrogen source (Fig. 4b). Morphology and identification of the fungus The anthracnose fungus on Liriope platyphylla found (Plate 1-D-H) Perithecia were erumpent, black, at Ibaraki Prefecture was apparently different from subglobular, 70-110μm in diam. Asci were clavate, Colletotrichum omnivorum Halsted [A synonym of 8-spored, 37-50×7.5-10μm. were hyaline, Colletotrichum dematium (Persoon: Fries) Grove] record- continuous, fusoid, often inequilateral, 14-21×5-5.5μm. ed on L. graminifolia Bak, from Tokyo6). The former Acervuli were erumpent, 50-100μm in diam., without has elliptic to cylindric conidia, whereas the latter has setae. Conidia were hyaline, elliptic, continuous, 15- falcate to crescent ones. The former fungus was 22.5×4.5-5.5μm. identified as Glomerella cingulata (Stoneman) Spaulding Morphology of the fungus described above was includ- et Schrenk [Anamorph: Colletotrichum gloeosporioides ed within the range of Glomerella cingulata and its (Penzig) Penzig et Saccardo] and was added as a second anamorph Colletotrichum gloeosporioides described on anthracnose fungus of Liriope. Through inoculation various plants7). Hence, an additional anthracnose tests and field observations, pathogenicity of the fungus fungus on Liriope was identified as G. cingulata on Liriope seemed to be relatively weak. The disease (Stoneman) Spaulding et Schrenk. first develops on old leaves in late autumn and becomes Pathogenicity (Plate 1-C) (1) On Liriope: Clear serious the next spring. Spots rapidly enlarge, finally leaf spots developed around wounds 4 days after spray- resulting in many blighted leaves. Perithecia and acer- ing a conidial suspension or putting a piece of mycelial vuli are produced simultaneously on blighted leaves. colony. No spots were produced from inoculations on This Liriope isolate belongs to an isolate group of nonwounded leaves. Numerous acervuli with pinkish Glomerella cingulata having an optimum temperature conidial masses were produced on the inoculated spots. from 25 to 30℃ for mycelial growth, together with (2) On apple fruit: Anthracnose spots developed from isolates from acacia5), amaryllis2), black locust4) and inoculations on wounded . Pale brown spots New Zealand hemp2). The other group of G. cingulata

* Department of International Agricultural Development , Sakuragaoka 1-1-1, Setagaya-ku, Tokyo 156-8502, Japan 東京農業大学国際農業開発学科 ** Present address: Taiwan Agricultural Chemicals and Toxic Substances Research Institute , 11 Kuang Ming Road, Wufeng, Taichung Hsien, Taiwan 413, ROC 台 湾 農 業 薬 物 ・毒 物 試 験 所 Ann. Phytopathol. Soc. Jpn. 64 (1). February, 1998 39

Fig. 3. Mycelial growth on PSA after 7 days. a: Fig. 1. Germination of conidia on water-agar. a: Ger- Growth at different temperatures, b: Growth at mination and time at 25℃, b: Germination and different H-ion concentrations. temperature after 24hr.

Fig. 2. Growth of mycelial colony on agar media (after

7 days at 25℃).

having an optimum temperature for mycelial growth at from 20 to 25℃, is composed of isolates from camellia3), chestnut9) and citrus8), etc. The present isolate showed best growth on Richard's solution agar, but grew poorly on Saito's soy agar. These cultural characteristics were similar to those of amaryllis and New Zealand hemp isolates, but were different from those of the other isolates of Glomerella cingulata cited above. The utilization of carbon sources Fig. 4. Mycelial growth on Hopkins' medium after 7 in the Liriope isolate coincided well with that of the days at 25℃. a: Influence of carbon sources, b:

New Zealand hemp-isolate2), but was different from the Influence of nitrogen sources. other isolates. That it was a good utilizer of KNO3 and NaNO3, but not of (NH4)2SO4 as a nitrogen source, was Ann. Phytopathol. Soc. Jpn. 61: 604-605 (in Japanese). also in accordance with the amaryllis- and New Zealand 2. Chen, C.-H., Kobayashi, T. and Kagiwata, T. (1997). hemp-isolates2), but not with the other isolates of G. New diseases on three ornamental plants-Powdery cingulata. From these facts, the species designated as mildew of pyracantha and anthracnoses of amaryllis Glomerella cingulata may be composed of many isolates and New Zealand hemp. J. Agric. Sci. Tokyo Nogyo having different cultural characteristics. Daigaku (Tokyo Univ. of Agric.) 42 (2): 75-86. 3. Ito, K., Chiba, O., Ono, K. and Hosaka, Y. (1956). The authors express their deep thanks to the members of Studies on some anthracnoses of woody plants III. Laboratory of Tropical Crop Protection, Department of Anthracnose affecting the fruit of L. International Agricultural Development, Tokyo University Bull. Gov. For. Exp. Stn. 83: 65-88. of Agriculture, especially to Dr. Keiko Natsuaki, for their 4. Ito, K. and Kobayashi, T. (1958). Studies on some encouragement and help during the present study. anthracnoses of woody plants V. Anthracnose fungi of black locust. Bull. Gov. For. Exp. Stn. 108: 1-29. 5. Ito, K. and Shibukawa, K. (1956). Studies on some Literature cited anthracnoses of woody plants IV. A new anthracnose of 1. Chen, C.-H. and Kobayashi, T. (1995). Anthracnose of Acacia with special reference to the life history of the Liriope graminifolia caused by Glomerella cingulata. causal fungus. Bull. Gov. For. Exp. Stn. 92: 51-64. 40 日本植物病理学会報 第64巻 第1号 平成10年2月

6. Iwata, Y. (1941). Colletotrichum omnivorum Halst. on 茨 城 県 取 手 市 で 発 生 し た ヤ ブ ラ ン 炭 疽 病 の 病 原 菌 は,岩 田 Liriope graminifolia Bak. f. Ann. Phytopathol. Soc. Jpn. (1941)の 報 告 し た 鎌 形 分 生 子 を持 つColletotrichum omnivo- 11 (1): 92-93. rum (=C. dematium)と は異 な り,子 の う胞 子 の ほ か に 円 筒 ・ 7. Kishi, K. et al. eds. (1988). Plant Diseases in Japan. 楕 円 形 の分 生 子 を 持 つ た め,Glomerella cingulataと 同 定 した 。 Zenkoku-Noson-Kyoiku-Kyokai, Tokyo (in Japanese). また 接 種 に よ り本 病 菌 の 病 原 性 を 確 認 し,ヤ ブ ラ ン 炭 疽 病 菌 の 一 つ と し て 追 加 し た 8. Togashi, K. (1949). Biological Characters of Plant 。 本 病 は成 熟 葉 に 晩 秋 か ら発 病 し,翌 春 激 Pathogens. Temperature Relations. Meibundo, Tokyo. し くな る。 本 菌 分 生 子 の 発 芽 適 温 は25℃ で,2時 間 後 か ら発 芽 9. Uchida, K. (1981). Studies on the ecology and control す る。 菌 叢 の 生 育 適 温 は30℃ で,高 温 型 に属 す る。好 適 培 地 は of anthracnose rot of Japanese caused by リチ ャ ー ズ 寒 天 培 地 で,斉 藤 氏 し ょ う ゆ 寒 天 培 地 で は生 育 が 劣 Colletotrichum gloeosporioides Penzig. Bull. Ibaraki り,ア マ リ リス お よ び マ オ ラ ン分 離 株(陳 ら,1997)と 似 た 傾 向 Hortic. Exp. Stn. Spec. Issue 6: 1-70. を 示 した 。 ま た 糖 の な か で は果 糖 を よ く利 用 す るが し ょ糖 で は 生 育 が 劣 り,チ ッ ソ源 で は硝 酸 カ リ と硝 酸 ナ ト リ ウ ム を よ く利 和 文 摘 要 用 し,硫 酸 ア ンモ ニ ウ ム は ほ とん ど利 用 し な い 。 これ ら は マ オ ラ ン炭 疽 病 菌 と相 似 た 傾 向 で あ っ た 。 小 林 享 夫 ・陳 忠 和:Glomerella cingulataに よ る ヤ ブ ラ ン (Received August 27, 1997; Accepted October 16, 1997) 炭 疽 病-病 原 追 加

Explanation of plate

Plate I Anthracnose of New Zealand hemp caused by Glomerella cingulata (Anamorph: Colletotrichum gloeosporioides). A: Symptom on a diseased bush in May. B: Close-up of symptom. C: Result of an inoculation with conidial suspension after 7 days (Left: Control for wound inoculation; Center: Wound inoculation; Right: Nonwound inoculation). D: Perithecia developed on leaf lesion. E: Asci. F: Ascospores. G: Acervulus on the same lesion having perithecia. H: Conidia.

[Scale (-): D and G=20μm; E, F, and H=10μm. Phase contrast: E, F and G]