山西农业大学学报（自然科学版）2016，Vol.36Issue(7)：483-488,6.
山西黄芪根际固氮菌的分离与应用
Isolation and application of nitrogen-fixing bacteria in rhizosphere of Astragalus membranaceus Bunge in Shanxi
摘要
Abstract
[Objective]Astragalus membranaceus Bunge (AMB)is an important herb that has been used in traditional Chinese medicine for centuries,and Hunyuan County of Shanxi province is one of the most important planting bases for AMB.Nitrogen fertilizer input for AMB production in China is very high.It is essential to reduce nitrogen fertilizer in-put and thus cultivation cost while achieving a high yield for sustainable and environmentally friendly AMB production. Research on biological nitrogen fixation has increased significantly because of its potential importance to the economy and the environment.AMB plants can obtain nitrogen from biological nitrogen fixation via diazotrophs.The aim of this work was to screen and identify nitrogen-fixing bacteria from the rhizosphere of AMB cultivated in Hunyuan County, Shanxi province,and to demonstrate their potential for nitrogen fixation with AMB as well as plant growth promotion. [Methods]120 nitrogen fixing strains were isolated from soil samples using Ashby nitrogen free medium.Two strains of them,t1 6 and t21,with strong ability of nitrogen fixation were screened out according to the ability of nitrogen fixa-tion,growth speed and other characteristics in further screening with nitrogen fixing medium.To demonstrate their potential for nitrogen fixation with AMB and growth promotion activities,the bacterial liquid of the two isolates were used to soak AMB seeds and inoculate into AMB seedlings for 30 d at 28°C in a growth cabinet.[Results]Based on morphological detection,physiological and biochemical detection and 1 6S rRNA gene sequence analysis,the two strains of t1 6 and t21 were identified as Rhizobium sp.and Sinorhizobium sp.,respectively.Both of the two strains signifi-cantly promoted the growth of AMB seedlings.They also increased the nitrogen contents of dry weight by 14.23% to 18.67% and 13.10% to 18.77%,respectively,compared with the uninoculated controls.The bacterial liquids of T1 6 with 10 6 mL-1 and T21 with 10 8 mL-1 have the best effect.The conversion amount of nitrogen fixing in 30 days is a-bout 2.25 kilograms per hectare.[Conclusion]These promising nitrogen fixation bacteria isolates from the rhizosphere of AMB showed potential to promote AMB production via nitrogen fixation and other plant growth promoting func-tions.This will improve AMB production efficiency and reduce the environmental pollution that results from AMB pro-duction.关键词
固氮菌/黄芪/根际/分离/鉴定Key words
Nitrogen-fixing bacteria/Astragalus membranaceus/Rhizosphere/Isolation/Identification分类
生物科学引用本文复制引用
薛智权,唐中伟,李浩,周然,梁建萍..山西黄芪根际固氮菌的分离与应用[J].山西农业大学学报（自然科学版）,2016,36(7):483-488,6.基金项目
科技部“十二五”国家支撑计划项目(20110313002-2) （20110313002-2）
山西省科技攻关项目(20110313002-2) （20110313002-2）
山西农业大学博士项目(XB2008022) （XB2008022）
