台灣玫瑰黑腐病之病原菌形態與生理特性

Morphological and Physiological Charateristics of Cylindrocladium scoparium, the Causal Agent of Rose Black Rot

鄭吉助( C.C Cheng) ； 黃振文( J. W Huang)

《植物病理學會刊》 12卷2期 (2003/06) Pp. 85-92

https://doi.org/10.6649/PPB.200306_12(2).0003

摘要

在埔里與新社玫瑰切花栽培田中，發現玫瑰花扦插苗與成株出現莖基部褐變、壞死與龜裂的病徵，受害根部組織則呈現黑變腐取的症狀。將罹病株分離獲得的菌株，回接於玫瑰花扦插苗，可以引起如田病株般的病徵。將病原菌CS-01與CS-05兩菌株分別培養在馬鈴薯葡萄糖瓊脂培養基平板上，菌落呈深黃褐色，分生孢子柄直立透明，有２至３又狀整齊分枝，每一孢子柄末端著生2至3個瓶狀枝；菌體有一長絲狀無性附絲，附絲頂端膨大成橢員形泡囊狀；分生孢子長柱形，透明，有單一隔膜，大小為38.1-44.6X5.9-6.1 μm，孢子於瓶狀枝上單生，可群聚成束狀；厚膜孢子褐黑色，大小為9.2-12.2X6.8-8.4μm，經鑑定為Cylindrocladium scoparium Morgan。本菌CS-01與CS-05菌株最適生長溫度介於24-28°C間，最適分生孢子發芽的酸值為pH6至9。利用病菌土接種法，發現玫瑰花扦插苗的發病百分率，會隨著接種菌量濃度的增加，愈趨嚴重。

關鍵字

玫塊花 ； 玫瑰黑腐病菌 ； 病原性 ； 病原菌鑑定 ； 形態 ； 生理

並列摘要

Recently, commercial plantings of rose (Rosa hybrida L.) at Puli and Shinshe areas in central Taiwan were damaged by an unknown disease. Symptoms consisted of a blackening of the root cortex, discoloration of lower stem, sometimes accompanied with longitudinal cracking. Severe root infection resulted in heavy mortality in rose cutting seedlings and plants. A species of Cylindrocladium was consistently isolated from disease portions of roses on 2% (w/v) water agar. Pathogenicity was confirmed by inoculating two isolates,CS-01 and CS-05 respectively onto rose cutting seedlings for 7 days under high humidity (RH＞95%) at 28 oe. Discoloration of stem bark and wood similar to the field symptoms developed on the inoculated plants. On potato dextrose agar, the growth rate of the fungus was rapid. Colonies reached 55.3-59.4 mm diameter for 6 days at 28°C, with yellowish to deep brown. Conidiophore upright, hyaline, regularly and repeatedly dichotomously or trichotomously branched, each terminating in two or three phialides, typically with a slender elongated sterile branch tenninating in an ellipsoid swelling; Conidia hyaline, 38.1-44.6 x5.9-6.1μm, 2-celled, cylindrical, borne singly but held togehter in bundles with mucilage. chlamydospores produced abundantly, globose to oblong, yellow-brown, single cell, 9.2-12.2x6.8-8.4μm. Thus, the fungus was identified as Cylindrocladium scoparium Morgan. The optimum temperature for conidial germination and mycelial growth of both isolates was at 24-28°C. The optimum pH value for conidial germination of C. scoparium was between 6-9. The optimum temperature for both infection on rose cuttings was at 24-28°C

並列關鍵字

Cylindrocladium scoparium ； identification ； morphology ； pathogenicity ； physiology ； Rosa hybrida