巴西固氮螺菌Yu62的EGFP标记及其在小麦体内的定殖研究

Colonization of Azospirillum brasilense Yu62 in Wheat Via EGFP

以质粒pEGFP-C1为模板,采用PCR方法特异性扩增增强型绿色荧光蛋白(EGFP)基因全长序列,将其与原核表达载体pVK-100连接,构建成重组载体pVK-EGFP。利用电转化法将重组载体导入巴西固氮螺菌Yu62中,得到EGFP标记菌株。用EGFP标记菌接种小麦‘小偃107’种子,室内限菌条件下培养10 d后,用荧光显微镜观测标记菌在小麦体内的定殖规律并观察接菌植株的田间生长状况。结果显示,巴西固氮螺菌Yu62能定殖于小麦根毛区、茎组织的细胞间隙等部位,而且接菌小麦‘小偃107’植株在根系发育、株高、分蘖数等方面比对照有较明显的优势。研究表明,巴西固氮螺菌Yu62能够定殖于小麦根茎内,并具有促进植物生长的作用。

The full-length gene encoding the enhanced green fluorescent protein（EGFP） was amplified via PCR reaction by using the prokaryotic expression vector pEGFP-C1 as the template,followed by ligation with plasmid pVK-100 whereupon a recombinant plasmid pVK-EGFP was constructed.The plasmid was transferred into the strain Azospirillum brasilense Yu62 by electroporation.A breed,＇Xiaoyan 107＇ were inoculated with the labeled strain and then the pattern of colonization and the growth of the wheat was observed with inverted fluorescence microscope after 10 days inoculation in sterilized glass tubes in a plant growth cabinet.The result indicated that A.brasilense Yu62 was capable of colonizing in intercellular spaces of the stem tissue and the roots hair tissue.Comparison with the control plants showed significant advantage in terms of root developmental characteristics,plant height and tiller number of the inoculated plants in the field.These results implied that A.brasilense Yu62 could present in root and stem tissue and enhance the growth of the wheat.