金線連根圈分離木黴菌菌株之生物特性

蔡金池(C. C. Tsai) ； 曾德賜(D. S. Tzeng) ； 謝式坢鈺(S. P. Y. Hsieh)

《植物病理學會刊》 17卷2期 (2008/06) Pp. 127-142

https://doi.org/10.6649/PPB.200806_17(2).0004

摘要

本研究旨在釐清分離自台灣金線連(Anoectochilus formosanus Hayata)根圈，並經證實對金線連莖腐病（Fusarium oxysporum Schl.引起）具防治應用潛力之TA與PT103兩木黴菌菌株特性。兩菌株同樣分別以30與37℃爲最適與最高生長溫度，且皆能產生厚膜孢子。唯其中PT103菌株具氣生菌絲且生長較爲快速，分生孢子粳爲直立型、黏帶黴菌(Gliocladium spp.)形態，不具無限生長之無性生殖絲，分生孢子圓至橢圓形，表面呈細疣狀突起；相較TA菌株生長較慢，唯其能利用蜜三糖，並可產生異腈類(isonitrile)抗生物質及明顯的可可氣味，分生孢子便多爲對稱分枝，其上著生之瓶狀枝呈瘦長瓶壺形，分生孢子圓形或近卵圓形，表面具有明顯不規則金字塔型疣狀突起。綜合上述形態、生理特性，可將PT103菌株歸屬於Trichoderma virens (Miller et al) Arx，並將TA菌株歸屬於T. asperellum (Samuels Liechfeldt & Nirenberg)。此二供試菌株另經萃取、選殖及解序其rDNA ITS序列，所獲得結果經與NCBI資料庫既有木黴菌菌株序列資料比對並分析其親緣關係，其結果亦證實與上述利用形態特性鑑定所獲結論一致，本文爲可供生物防治應用菌株T. asperellum於台彎地區首次紀錄。

關鍵字

生物防治 ； 鐮胞菌 ； 台灣金線連 ； 木黴菌 ； 內轉錄區間親緣性

並列摘要

The main objective of this investigation was to elucidate the species characteristics of Trichoderma TA and PT103 strains which were isolated from rhizosphere of Anoectochilus formosanus Hayata and have been shown effective for bio-controlling stem rot infection by Fusarium oxysporum Schl. on A. formosanus. Both tester strains produced chlamydospores on culture and showed a similar optimum and maximum growth temperature at 30 and 37℃, respectively. However, among them PT103 strain appeared to grow faster and produced abundant aerial mycelia. And upon conidiation, it produced long erect conidiophores with characteristic Gliocladium-type morphology and no apical sterile elongation. The conidia appeared to be spherical to subglobose structure covered with abundant tiny thin warts. As a comparison, TA strain grew considerably slower, utilized melezitose as sole carbon source and produced antifungal isonitrinic acids and unique coconut smells. Also, upon conidiation, it produced conidiophores predominantly in paired branching, and among them bore slender-ampulliform phialides with characteristic viride-type morphology. The conidia were ovoid to subglobose structure covered with conspicuous irregular pyramidal warts. The morphological characteristics indicated clearly PT103 strain a member of T. virens (J. Miller, Giddens & Foster) and TA strain a member of T. asperellum (Samuels, Liechfeldt & Nirenberg). By polymerase chain reaction, the rDNA internal transcribed spacer (ITS) sequence of the two tested strains were amplified and sequenced. Results obtained from the pair-wise comparison of the sequence data of comparative strains available from NCBI and the phylogenetic analysis supported fully the above species identification based on the morphological characteristics. This is the first report of T. asperellum as a biological control agent in Taiwan.

並列關鍵字

Biological control ； Fusarium oxysporum Schl:Fr ； Anoectochilus formosanus Hayata ； Trichoderma asperellum ； Tyichoderma virens ； ITS phylogeny