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Title: | 木黴菌防治樹木褐根病之探討 Application of Trichoderma spp. for controlling brown root rot disease of trees |
Authors: | Hao Chou 周昊 |
Advisor: | 鍾嘉綾(Chia-lin Chung) |
Keyword: | 褐根病,木黴菌,殺菌劑,生物防治,化學防治, brown root rot,Trichoderma,fungicide,biological control,chemical control, |
Publication Year : | 2018 |
Degree: | 碩士 |
Abstract: | 有害木層孔菌 (Phellinus noxius) 造成的樹木褐根病可危害超過200種以上的闊葉樹及針葉樹,本病於感染初期並不會有明顯症狀,往往發現病徵時已難以防治。現行褐根病防治方法包括邁隆燻蒸、系統性殺菌劑澆灌等,但不當使用化學藥劑有可能破壞環境、傷害非目標生物。Schwarze等人 (2012) 及Tang等人 (2016) 的in vitro實驗指出,木黴菌可抑制P. noxius生長、防止木材遭P. noxius腐朽,Schubert等人 (2008) 亦發現木黴菌可有效防治木材腐朽菌感染樹木傷口。本研究針對4株P. noxius及4株Trichoderma菌株進行測試,首先透過1/2 馬鈴薯葡萄糖瓊脂 (PDA) 上之對峙培養,瞭解木黴菌對P. noxius之生長抑制效果;再將P. noxius及木黴菌依不同先後順序接種於正榕 (Ficus microcarpa) 木塊,發現先處理木黴菌可減少P. noxius造成之乾重損失;之後選擇具潛力之其中一株木黴菌T. asperellum TA,以土壤澆灌法處理根部接種P. noxius 2248 前、後之枇杷苗 (Eriobotrya japonica),發現可有效延緩萎凋,且先處理木黴菌可達到良好防治效果,顯示預防勝於治療之重要性。由接種P. noxius 2248及T. asperellum TA之枇杷根組織進行表面消毒後,於選擇性培養基上分離培養,各處理組之P. noxius分離率與樹苗萎凋發生率趨勢一致,而即使在單純處理T. asperellum TA之組別,木黴菌之分離率仍低 (粗根11.1%、細根4.2%),顯示其在枇杷根部組織內之定殖能力弱。為增加防治藥劑選項,及探討結合木黴菌生物防治法與化學防治法之可行性,本研究挑選相對低毒性之18種系統性殺菌劑,測試其在含藥PDA培養基上對4株P. noxius及4株Trichoderma菌株之抑制率,發現環克座、依普座於1 ppm下仍能有效抑制P. noxius,而木黴菌對三泰芬、滅普寧之感受性較低,可作為未來病害防治管理之參考。 Brown root rot disease, caused by Phellinus noxius, is one of the most destructive tree diseases that has raised much public attention. Trees infected with P. noxius do not show obvious symptoms at early stages. Usually when brown root rot is diagnosed, it is too late for disease control. The methods currently applied for brown root rot control include soil fumigation using Dazomet and drench treatment using systemic fungicides. However, misuse of chemicals may cause environmental pollution and harmful effects to non-target organisms. In vitro experiments by Schwarze et al. (2012) and Tang et al. (2016) showed that Trichoderma sp. can inhibit the growth of P. noxius and prevent wood blocks from P. noxius degradation. Schubert et al. (2008) also found that application of Trichoderma sp. can reduce the infection of wood decay fungi through wounds. In this study, we first tested antagonistic activity of 4 different Trichoderma isolates against 4 different P. noxius isolates by dual culture on 1/2 potato dextrose agar (PDA) medium. Inoculation of Trichoderma and/or P. noxius isolates on wood blocks of Ficus microcarpa showed that pretreatment with Trichoderma significantly reduced the loss of dry weight caused by P. noxius. A single Trichoderma isolate showing strong and stable antagonistic activity, T. asperellum TA, was further confirmed to be effective in delaying the wilting of P. noxius 2248–inoculated loquat seedlings (Eriobotrya japonica) in the pot assay. Both wood block and pot assays suggested that better biocontrol efficiency can be achieved by applying Trichoderma sp. prior to the infection of P. noxius. Loquat roots inoculated with P. noxius 2248及T. asperellum TA were examined by surface sterilization and cultivation on selective media. The isolation rates of P. noxius were correlated with the wilting rates of loquat seedlings in different treatments. Low isolation rates of Trichoderma were observed, even from the roots only treated with T. asperellum TA (11.1% of coarse roots and 4.2% of fine roots), indicating weak colonization ability of T. asperellum TA in loquat roots. To provide more options for chemical control, as well as to evaluate the feasibility of combining Trichoderma and fungicides for disease management, 18 systemic fungicides that are relatively lower toxic were tested for inhibition of the mycelial growth of 4 Trichoderma isolates and 4 P. noxius isolates on PDA amended with individual chemical. Cyproconazole and epoxiconazole were effective in suppressing P. noxius at 1 ppm, and Trichoderma had lower sensitivity to triadimefon and mepronil. These findings provide new insights into the control of brown root rot. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/71180 |
DOI: | 10.6342/NTU201802034 |
Fulltext Rights: | 有償授權 |
Appears in Collections: | 植物醫學碩士學位學程 |
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