Distribution and Analysis of plasmid-like DNA among Rhizoctonia Spp. in Taiwan

臺灣絲核菌質體狀DNA的分佈及分析

陳隆鍾(Lung-Chung Chen) ； 廖家德(Jia-The Liao) ； 楊相哲(Hsiang-Che Yang) ； 劉文禎(Wen-Chen Liu)

《Fungal Science》 19卷3&4期 (2004/12) Pp. 133-147

https://doi.org/10.7099/FS.200412.0133

摘要

由數種蔬菜、花卉及經濟作物分離而得之絲核菌菌株，大部分為多核並以第四菌絲融合群為主。偶爾會出現第一菌絲融合群、第三菌絲融合群及第2-1菌絲融合群。由蘭科植物所分離者為雙核絲核菌，每一營養菌絲節具有明顯之雙核。質體狀去氧糖核酸之地理分佈廣泛存在於供試菌株中，但蘭科植物所分離之絲核菌菌株不具質體狀去氧核糖核酸，其所帶質體狀DMA這分布具有歧異性，其分子量大小約在2.4至2.7 Kb之間，但彼此間之質體狀去氧核糖核酸均具同源性。以分離株SH-O-1及B sp-5的質體狀DNA進行biotin標幟製備核酸探針，進行南方漬染分析，結果顯示，可確定其為線形分子，同時其亦對S1核酸內切酶(S1 endonuclease)及ExoⅢ外切酶(exonuclease Ⅲ)、λ外切酶(λ exonuclease)具有抗性并具寄主專一性。進一步將SH-O-1分離株所帶有之質體狀DNA(plSH-O-1;約2.5kb)進行限制酶圖譜分析，其中BamHI、EcoRV、PstXI、Sacl、XbaI、NotI及BstXI并未測出具有切位，而HincII、PvuII及SmaI則含有1切位，ApaI及XhoI則有2個切位，HindIⅡ則含有4個切位，從限制酵圖譜及其切位等特性，很明顯地了解質體狀DNA之分佈特性和地理分佈之演化同源性有關。

關鍵字

立枯絲核菌 ； 絲核菌 ； 質體狀DNA

並列摘要

Isolates of Rhizoctonia spp. collected from various vegetables, flowers, and other cultured crops were multi-nucleate and predominantly R. solani AG-4. Some of the AG-1, AG-3, and AG2-1 anastomosis groups were occasionally collected. The binucleate Rhizoctonia from orchidaceous plants had two nuclei per vegetative cell. Plasmid-like DNA lines in Rhizoctonia spp. were geographically widely distributed and occurred in tested isolates. But no p1DNA was detected from orchidaceous plants. These plasmid-like DNAs (plDNAs) varied from 2.4 to 2.8 kb in size, and showed sequence homology to the same AG group p1DNAs (p1DNA SH-O-1 and p1DNA B sp-5). Results of sequence homology among the pIDNAs fractionated from the same anastomosis group showed host-specific characterization; therefore, these p1DNAs were resistant to S1 endonuclease, exonuclease III, and λ exonuclease, and it was revealed through the electron microscopic analysis that all of the p1DNAs were linear molecules. A physical map was determined by single and double enzyme digestions, using restriction enzymes of BamHI, EcoRV, KpnI, PstI, BstI, XbaI, and NotI which have no cut sites on plSH-0-1. On the basis of the characterization with restriction endonuclease, it was apparent the plDNAs are evolutionarily homologous with geographically widely comparisons of different origins.

並列關鍵字

plasmid-like DNAs ； Rhizoctonia solani Kühn ； Rhizoctonia spp.