具有增强共生有效性的茎瘤固氮根瘤菌叠氮化物抗性突变体。

Azide-resistant mutants of Azorhizobium caulinodans with enhanced symbiotic effectiveness.

作者信息

Saini I, Sindhu S S, Dadarwal K R

机构信息

Department of Microbiology, CCS Haryana Agricultural University, Hisar-125 004, India.

出版信息

Folia Microbiol (Praha). 2001;46(3):217-22. doi: 10.1007/BF02818536.

DOI:10.1007/BF02818536

PMID:11702406

Abstract

Azide-resistant mutants of Azorhizobium caulinodans strains Sb3, S78, SrR13 and SrS8 were isolated and screened for nitrate reductase activity. Selected nitrate reductase negative mutants were inoculated on Sesbania bispinosa and S. rostrata under sterile conditions in chillum jars to study their symbiotic behavior. Azide-resistant mutants exhibited either similar or higher symbiotic effectiveness than the parent strain after 30 d of plant growth. Nodule mass, nitrogenase activity and uptake hydrogenase activity of the mutants varied depending on the host as well as on the plant growth stage. In comparison to wild-type parent strains, four azide-resistant mutants, Sb3Az18, S78Az21, SrR13Az17 and SrS8Az6 showed significant increase in nodulation and nitrogen fixation as well as shoot dry mass of the inoculated plants.

摘要

分离出了茎瘤固氮根瘤菌菌株Sb3、S78、SrR13和SrS8的叠氮化物抗性突变体，并对其硝酸还原酶活性进行了筛选。挑选出的硝酸还原酶阴性突变体在无菌条件下接种于双刺田菁和喙田菁上，置于土罐中以研究其共生行为。在植株生长30天后，叠氮化物抗性突变体表现出与亲本菌株相似或更高的共生效率。突变体的根瘤质量、固氮酶活性和吸氢酶活性因宿主以及植株生长阶段而异。与野生型亲本菌株相比，四个叠氮化物抗性突变体，即Sb3Az18、S78Az21、SrR13Az17和SrS8Az6，在接种植株的结瘤、固氮以及地上部干质量方面均有显著增加。