由Corynespora cassiicola引起之沙漠玫瑰葉斑病
Other Title
Corynespora cassiicola Causes Leaf Spot on Adenium obseum in Taiwan
Journal
台灣農業研究
Journal Volume
74
Journal Issue
4
Start Page
485
End Page
495
ISSN
2790-086X
Date Issued
2025-12-07
Author(s)
Abstract
2022 年 7 月中旬於彰化縣永靖鄉某一處園區，發現沙漠玫瑰葉片上產生褐色圓斑與不規則形病斑，嚴重時造成罹病葉片黃化與落葉。本研究自罹病葉片分離到 1 種真菌，培養於馬鈴薯葡萄糖瓊脂培養基 (potato dextrose agar; PDA) 培養基上，菌落為灰白色至灰色，培養基背面呈棕色至黑色。本菌之分生孢子呈棍棒狀或圓柱狀，直或略彎，淡褐色，具有多個隔膜，頂端鈍圓。依據本病害之病徵表現、病原菌形態特徵以及分子序列鑑定結果，將此菌鑑定為 Corynespora cassiicola。經人工接種試驗確認 C. cassiicola 對沙漠玫瑰葉片具有病原性，完成柯霍氏法則，證明此菌可為害沙漠玫瑰葉片造成葉斑病。本菌最適菌絲生長溫度為24−32℃，最適孢子發芽溫度為 20−28℃。測試殺菌劑對其菌絲生長與孢子發芽影響，結果顯示賽普護汰寧、百克列及快得寧可有效抑制本菌菌絲生長，而快得寧、鋅錳乃浦及賽普護汰寧可顯著降低此病原菌之孢子發芽。以上本研究報導沙漠玫瑰葉斑病之病徵表現、病原形態、生長適溫及藥劑敏感性等資料，可作為將來病害鑑定與防治時之參考。本文為臺灣首次紀錄由 C. cassiicola 引起的沙漠玫瑰葉斑病報告。
In July 2022, leaf spot disease of desert rose (Adenium obseum) occurred in the Changhua area, with symptoms showing brown, round, or irregular-shaped lesions on leaves. In severe cases, the affected leaves yellowed and dropped off prematurely. In this study, a fungus was isolated from the diseased leaves and cultured on potato dextrose agar (PDA) medium. The colony was grayish-white to gray, with the reverse side of the medium turning brown to black. The conidia of this fungus were cylindrical or barrel-shaped, straight or slightly curved, light brown, with multiple septa, and blunt at the apex. Based on the symptoms of the disease, the morphological characteristics of the pathogen, and molecular sequencing identification results, this fungus was identified as Corynespora cassiico-la. Artificial inoculation tests confirmed that C. cassiicola was pathogenic to desert rose leaves, and Koch’s postulates were completed, proving this fungus to be the causal agent of desert rose leaf spot disease. The optimal temperature was 24−32℃ for mycelial growth of C. cassiicola and 20−28℃ for spore germination. Mycelial growth of the pathogen was effectively inhibited by Cyprodinil + Fludioxonil, Boscalid, and Oxine-copper. Spore germination of the pathogen was inhibited by Ox-ine-copper, Mancozeb, and Cyprodinil + Fludioxonil based on fungicide screening conducted in vitro. The findings of this study on the disease symptoms, pathogen morphology, growth temperature, and fungicide sensitivity can serve as a reference for future disease identification and control efforts. This is the first report of leaf spot disease on desert rose caused by C. cassiicola in Taiwan.
Subjects
沙漠玫瑰
葉斑病
葉斑病菌
藥劑篩選
Desert rose (Adenium obseum)
Leaf spot
Corynespora cassiicola
Fungicides screening
Publisher
農業部農業試驗所
Type
journal article
File(s)![Thumbnail Image]()
Loading...
Name
74-4-7.pdf
Size
2.98 MB
Format
Adobe PDF
Checksum
(MD5):d93eb9d9255ae5d86ceb98771eb442fd