Activity of nitrogen fixation and nitrogen assimilation enzymes in soybean plants inoculated with Bradyrhizobium japonicum strains.
In studying the symbiotic associations of 8 Bradyrhizobium japonicum strains with two soybean varieties (NS-10 and NS-21), we determined the activity of nitrogen fixing (nitrogenase, NG) and nitrogen assimilation (glutamine synthetase, GS) and glutamate dehydrogenase (GDH) enzymes and the content of soluble proteins. The number of nodules was not in correlation with dry matter mass and nitrogen content. Dry matter mass and nitrogen content in the nodules of the soybean varieties in association with Bradyrhizobium strains 1, 1a, 2b, 2/1, 1003 and 8k turned out to be significantly higher than mass and nitrogen content of those in association with B. japonicum strains 17z and 2k. The results obtained indicate that the activity of the enzymes NG and GS in plants correlates with nitrogen fixation for both varieties on average, while the activity of GDH enzyme is conditioned by the specificity of variety and the Bradyrhizobium japonicum strains.
Milić
V
V
Institute of Field and Vegetable Crops, Novi Sad, Yugoslavia.
Mrkovacki
N
N
Popović
M
M
D009586:Nitrogen Fixation; D009591:Nitrogenase; D012230:Rhizobiaceae / Q000502:physiology*; D013025:Glycine max / Q000201:enzymology* / Q000382:microbiology; D013559:Symbiosis
D009591:Nitrogenase