Competence of Coniothyrium minitans in Preventing Infection of Bean Leaves by Sclerotinia sclerotiorum

Coniothyrium minitans抑制菌核病菌危害菜豆葉片的效果

Eric Bremer ； 黃鴻章(Hung-Chang Huang) ； Lorna J. Selinger ； J. Stephen Davies

《植物病理學會刊》 9卷2期 (2000/06) Pp. 69-74

https://doi.org/10.6649/PPB.200006_9(2).0005

摘要

本研究旨在探討應用離葉測定法來撿驗拮抗真菌Coniothyrium minitans柄孢子(pycnidospores)對控制菌核病菌(Sclerotinia sclerotiorum)子囊孢子(ascospores)危害菜豆葉片的效果。將每平方毫米(mm-2)含有8,80,或800個C.minitans柄孢子的懸浮液接種於菜豆花瓣上，經24或48小時之後，在接種菌核病菌之子囊孢子懸浮液。經這種處理花瓣放在菜豆之切離葉片上時，有顯著抑制菌核病菌的病斑在葉片擴展的效果，但如果將菌核病菌之子囊孢子先接種於花瓣上，則C.minitans柄孢子之處理時為最。經C.minitans高濃度(每平方毫米800個孢子)之處理的花瓣，於15,20,及25°C的環境下，均有顯著抑制葉片病斑擴展的效果；但是溫度升高到30°C時，因已接近臨高溫而沒有病斑形成。將C.minitans柄孢子直接噴布於菜豆葉片上，也有降低菌核病菌囊孢子入侵的作用，但效果不如將柄孢子先接種於花器再放置葉片上之處理。進一步實驗證實葉片或花器的水浸出液有刺激C.minitans柄孢子發芽及菌絲生長的功效。本研究證實用花器之類凋謝組織可以增進C.minitans防治菌核病菌子囊孢子危害菜豆的效果。

關鍵字

菜豆菌核病 ； 生物防治 ； 子囊孢子 ； 柄孢子 ； 離葉檢定法

並列摘要

The effectiveness of applying pycnidiospores of Coniothyrium minitans to bean flowers to protect bean leaves from infection by ascospores of Sclerotinia sclerotiorum was studied using a detached leaf assay. C. minitans fllinitans applied to bean flowers at 8, 80 or 800 spores mm-2 at 24 or 48 h prior to that of ascospores of S. sclerotiorum reduced lesion development on bean leaves caused by the pathogen. When applied at the same time or 24 h after S. sclerotiorum, the efficacy of C. minitans to suppress lesion development by S. sclerotiorum was reduced, especially at low application rates. C. minitans at 800 spores mm-2 applied to bean flowers suppressed lesion development by S. scierotiorul1l at 15,20 or 25°C. C. minitans applied to the surface of bean leaves also reduced the diameter of S. sclerotiorum lesions formed when flowers inoculated with ascospores of S. sclerotiorum were placed on the leaf surface, though less effectively than when C. minitans was applied directly to the bean flower. Water-soluble extracts of bean leaves or flowers stimulated spore germination and hyphal growth of C. minitans. Thus, colonization of senescent tissues such as bean flowers by C. minitans is an effective mechanism for suppression of white mold of bean caused by S.sclerotiorum.

並列關鍵字

White mokd of bean ； biological ； Sclerotinia Sclerotiorum ； ascospores ； Coniothyrium minitans ； pycnidiospores ； detached leaf assay