小花蕙蘭假球莖腐敗病菌感染途徑之研究

由Fusarium oxysporum 引起的假球莖腐敗病 (pseudobulb rot) 是台灣小花蕙蘭 (Oriental cymbidiums) 栽培的重要限制因子之一。農友為縮短植株生長期一般不採用組培苗，而是以慣行栽培之分芽繁殖為主，本研究嘗試比較組培苗、健株苗、病株苗及病株之第一代、第二代及第三代分株苗對假球莖腐敗病發生之影響，結果發現病株第一代分株苗移栽於盛有碎石栽培盆中，假球莖腐病的發病率高達100%；且病株第二代與第三代分株苗移栽後，其植株發病率仍為中等偏高，顯示病株苗或來自罹病植株之分株苗，為本病害重要感染源之一，因此採用健康分株苗為防治本病害之重要策略。小花蕙蘭假球莖腐敗病菌分離株 (F. xysporum Fo-50) 可在幼嫩與成熟假球莖傷口接種時，造成組織黑褐化腐敗病徵。另外，本研究進行傷口對假球莖腐敗病發生之影響試驗，結果發現剪根、假球莖針刺傷口及分拆分株苗產生傷口之植株接種假球莖腐敗病菌 (F. oxysporum Fo-50, Fo-51) 其發病率皆為100%，顯著高於無傷口處理植株 (25% 或更低)，顯示傷口為病害發生的重要因素。接著進一步接種試驗中，於「寶山報歲蘭」或「玉華四季蘭」品種中，將植株分拆產生傷口後3、7 及28 d 之分株苗，接種假球莖腐敗病菌 (F. oxysporum Fo-50, Fo-51)，其發病率分別為高 (75.0–100%)、中(50–75%) 及低等 (12.5–25%)。本研究結果可作為後續研擬小花蕙蘭假球莖腐敗病防治策略之重要參考依據。 Pseudobulb rot disease caused by Fusarium oxysporum is a major limiting factor of Oriental cymbidiums cultivation in Taiwan. In order to shorten the growth period, farmers usually use a shoot diving method for propagation instead of using tissue culture plantlets. However, the disease incidence of pseudobulb rot was up to 100% when the 1st generation shoot from the diseased mother plant were replanted in pots. Furthermore, the replanted plants of the 2nd and 3rd generation shoots from the diseased mother plants showed moderate high disease incidences, suggesting that the disease plantlets or generation shoots come from the disease plant were the major inoculum source. In the artificial inoculation tests, both the young and mature Oriental cymbidiums pseudobulbs showed similar disease incidence after individual inoculation with wound treatment. In another inoculation test, with wound treatment, including on roots, pseudobulbs, and seedlings, the inoculated plants showed 100% disease incidences, significantly higher than the no wound treatment (25% or less), indicating that wound was an important factor to promote the disease development. In the further inoculation tests, both of the most popular cultivars (C. sinense ‘Bao-shan’ cultivar and C. ensifolium ‘Yu-hua’ cultivar) showed high (75.0–100%), moderate (50–75%) and low (12.5–25%) disease incidence on the replanted plantlets 3, 7 and 28 days after pseudobulbs were separated, respectively. The results of this study provides an important reference for developing the further control measures of pseudobulb rot disease in Taiwan.

Subjects

小花蕙蘭

假球莖腐敗病

鐮孢病菌

發病生態

cymbidium

Pseudobulb rot

fusarium oxysporum

disease ecology

Publisher

農業試驗所

Type

journal article

File(s)

Name

72-3-6.pdf

Size

2.34 MB

Format

Adobe PDF

Checksum

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