天山北坡甜菜内生菌分离鉴定及其动态变化

对新疆昌吉和石河子两地种植的甜菜内生菌进行了分离、鉴定和分析,结果表明甜菜内生菌多属于细菌,其中假单胞菌 (Pseudomonas sp. )和芽孢菌类(Bacillus sp.)的分离频率分别在33.2%～59.2%和12.7%～28.1%,是甜菜植株中的优势内生菌群.16S rDNA 和 ITS 序列同源性比较和系统发育分析表明内生菌具有丰富的多样性.根中内生菌的多样性高于茎、叶,昌吉地区种植的甜菜中分离出的内生菌种类较多.从感病品种及生长不良甜菜植株中分离出的内生菌种类比较丰富.通过回接分离及利用扫描电镜观察内生菌在植物体内分布发现,内生菌能够定殖于甜菜块根.

Isolation and identification of endophytic microorganisms from sugar beet and dynamic changing in the north slope of Tianshan Mountain

Endophytic microorganisms isolated from the tissues of healthy sugar beets from Changji and Shihezi district in Xinjiang province were identified and investigated. The results showed that most of endophytic microorganisms of sugar beets belong to bacteria, in which Pseudomonas sp. and Bacillus sp. were the dominant communities with isolation frequency of 33.2%-59.2% and 12.7%-28.1%, respectively. The endophytic microorganisms were displayed a wide diversity by comparison their 16S rDNA and ITS sequences with GenBank using Blast software and analysis of phylogenetic tree. The biodiversity of endophytic microorganisms in roots of sugar beets were more than those of leaves, and the species of endophytic microorganisms in sugar beets from Changji district were more than those of Shihezi district. More endophytic microorganisms were isolated from poor growing seedlings and susceptible sugar beet cultivars than from the disease resistant counterparts. Endophytic microorganisms have been successfully re-isolated after inoculating sugar beet seedlings, in which endophytic microorganisms could colonize interior of the sugar beet roots by observation with scanning electron microscopy.