檬果果斑病之研究　Ⅰ.病徵及病原菌

Studies on Mango Fruit Ⅰ. Symptoms and Causal Organism

廖嘉信(Chia-Hsin Liao)

《中華農業研究》 21卷2期 (1972/06) Pp. 146-150

https://doi.org/10.29951/JARC.197206.0008

摘要

檬果果斑病爲臺灣檬果之新病害，民國五十八年發見以來，爲害日趨嚴重，一般認爲抗病力甚強之菜檨子（本地種），枝葉亦嚴重受害。果實之病斑發生在皮目上，初期有流膠及三角形裂縫，漸擴展呈黑褐色之星形，同時病斑突起，細菌分必物沿果皮流下。葉部病斑與1948年Patel氏等在印度發現者近似。本病亦在葉柄及幼枝發生。
病原經試驗結果證實爲一細菌性病害。病原體爲桿狀，大小約0.4~0.6×0.8~1.7μ，單胞或呈短鏈狀，Gram陰性，非抗酸性，無內生胞子及莢膜，具活動性之單極單鞭毛，在馬鈴薯葡萄糖培養基平板上爲圓形，白色或乳白色，中高、全緣之菌落，生長良好。肉汁培養液中，生長中等，混濁均勻，有微量粘性沈澱，表面有輪環。在Uschisky氏及Cohn氏液均不生長。本病原菌之生長適溫爲攝氏28~30度，氫離子在pH7.0時生長最好。在Glucose, saccharose, Starch, Trehalose, Dextrin, D-Galactose, D-Xylose, Raffinose Grycerin, D-Mannitol及Sorbitol培養基中産生酸，但不産生氣體，能水解澱粉和酪素。除Fs 33外，不能使硝酸鹽還原。能使白明膠液化，石蕊還原，不以産生吲嗓，產生硫化氫和觸酶之好氣性桿狀菌。據試驗結果證實，本病原之生理及形態與Patel氏等(1948)發現之Pseudomonas mangiterae-indicae近似，惟不能爲害Cashewnut。

並列摘要

The fruit spot of Mango, a new disease in Taiwan was found at Yu-Ching in 1969, the same disease had reported by Patel in India in 1948. The disease is characterized by appearing crack with clearing exudate at lenticels on fruits about at the 10th day after infection, then turning to deep brown stellate spots with raised and heavy bacterial exudate flows downward. The lesions are 1-5 mm in diameter, 2-3 mm in depth. The leaf lesions are angular, dark brown, water-soaked areas from 1-4 mm in diameter with clearing margin, rough and raised later. In severely affected ones, the most of fruits and leaves are failed down, sometimes the tender branch may infected.
The causal bacterium was isolated, it is a aerobic bacterium, rod-shaped 0.4-0.6×0.8-l.7μ in size, Single or short chain, not acid-fast, without endospore, motile by monotrichous flagellum. Potato-Dextrose Agar colony is circular, white to creamy white with entire margin, smooth, glistening, translucent. No growth in both Uschisky's solution and Cohn's.
The temperature range for growth of the bacterium is 8-36℃, the optimum temperature being 28-30℃. The pH range for growth is 4.0-10.0, the optimum being 7.0. Starch and casein are hydrolyzed, nitrates are not reduced except Fs 33, gelatin is liquefied, Litmus is reduced, no indole is produced, hydrogen sulfide is produced. Acid but no gas is produced from glucose, saccharose, starch, Trehalose, Dsxtrin, D-Galactose, D-Xylose, Raffinose, Grycerin, D-Mannitol and Sorbitol, no acid and gas are produced from L-Arabinose, Lactose, Maltose, Inulin, L-Rhamnose, D-Mannose and Salicin.
The causal bacterium affects Mangifera indica L. but does not infects Anacardiuinm occidentale L. (Cashew nut).