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.

Department of Microbiology CCS Haryana Agricultural University Hisar 125 004 India

Zobrazit více v PubMed

Appl Environ Microbiol. 1994 Oct;60(10):3815-32 PubMed

J Bacteriol. 1990 Mar;172(3):1676-80 PubMed

Plant Physiol. 1969 Dec;44(12):1666-8 PubMed

Appl Environ Microbiol. 1982 Dec;44(6):1385-8 PubMed

Annu Rev Biochem. 1994;63:675-716 PubMed

Microbiol Rev. 1994 Sep;58(3):352-86 PubMed

Microbiol Rev. 1995 Mar;59(1):124-42 PubMed

Trends Microbiol. 1994 Sep;2(9):318-24 PubMed

Plant Cell. 1996 Oct;8(10):1885-98 PubMed

Folia Microbiol (Praha). 1998;43(2):182-6 PubMed

J Bacteriol. 1989 Jan;171(1):465-72 PubMed

Mutat Res. 1988 Feb;197(2):313-23 PubMed

J Bacteriol. 1990 Mar;172(3):1647-55 PubMed

Competition among Bradyrhizobium strains for nodulation of green gram (Vigna radiata): use of dark-nodule strain

Preincubation of Mesorhizobium ciceri with flavonoids improves its nodule occupancy