中文摘要：

从核桃根部分离得到1株内生真菌G3,其发酵产物对多种植物病原真菌具有明显的抑制作用。故进一步对G3菌株进行分子鉴定和生物学特性研究,旨在为G3菌株发酵培养条件的优化与作为拮抗工程菌开发提供理论依据。核糖体内转录间隔区序列分析表明其与角担菌属（Ceratobasidium）在进化位置上最为接近,同源性为99%。生物学特性研究发现：G3菌株适宜生长温度为15～30℃,最适温度为25℃;在各光照条件下均能生长,但黑暗条件对生长更有利;pH5～8时均能正常生长,最适pH6～7;G3菌株可利用多种碳源、氮源,其中最适碳源、氮源分别为可溶性淀粉、蛋白胨,且有机氮源及偏酸性的环境利于G3菌株的生长。

英文摘要：

G3 is an endophytic fungus isolated from root of regia L. and its fermentation products showed strong antifungal activities to plant pathogenic fungi. The molecular identification and biological characteristics of endophytic fungi G3 were studied to provide evidence for optimization of fermentation and development engineering bacteria. Sequences analysis of ribosomal DNA showed that G3 had the highest homologous with Ceratobasidium. Biological characteristics research showed that the proper growth temperature of the strain was 15-30℃, the optimum temperature was 25℃. Darkness was beneficial to the growth of G3. The proper growth pH of the strain was 5-8, and the optimum pH was 6-7. The optimum carbon and nitrogen source were soluble starch and peptone, respectively. G3 strains could utilize many kinds of carbon source and nitrogen source, but preferred organic nitrogen source and acid condition.