Vitamin Requirements of Root Nodule Bacteria

Growth Factor Requirements of the Root Nodule Bacteria.

It is known that yeast or plant extracts markedly stimulate the growth of the root nodule organism in media of purified ingredients. An essential growth factor or superior source of nitrogen has been invoked to explain the results, but neither theory has a broad experimental basis. The results of Allyn and Baldwin (1930) suggest that the extracts may affect favorably the oxidation-reduction pot...

[Root nodule bacteria on leguminous plants].

Quantitative Evaluation of Acidity Tolerance of Root Nodule Bacteria

Quantification of acidity tolerance in the laboratory may be the first step in rhizobial strain selection for the Amazon region. The present method evaluated rhizobia in Petri dishes with YMA medium at pH 6.5 (control) and 4.5, using scores of 1.0 (sensitive, “no visible” growth) to 4.0 (tolerant, maximum growth). Growth evaluations were done at 6, 9, 12, 15 and 18 day periods. This method perm...

Use of potato extract broth for culturing root-nodule bacteria.

Liquid media containing potato extract and 1% of glucose or sucrose were used to culture root-nodule bacteria (rhizobia) in shaken Erlenmeyer flasks. For comparison, these bacteria were also cultured in yeast extract-mannitol broth (YEMB) as a standard medium. Proliferation of rhizobia was monitored by measuring optical densities (OD550) of the cultures and by plate counting of the viable cells...

Discovery of Novel Plant Interaction Determinants from the Genomes of 163 Root Nodule Bacteria

Root nodule bacteria (RNB) or "rhizobia" are a type of plant growth promoting bacteria, typified by their ability to fix nitrogen for their plant host, fixing nearly 65% of the nitrogen currently utilized in sustainable agricultural production of legume crops and pastures. In this study, we sequenced the genomes of 110 RNB from diverse hosts and biogeographical regions, and undertook a global e...