Dinkins, RD*; Koch, L.†; Sullivan ML†; Zhu, H.†* USDA-ARS, Forage-Animal Production
Research Unit, Lexington KY, USA;† USDA-ARS, US Dairy Forage Research Center …

High grain production of cereals has only been possible with high inputs of inorganic or
synthetic nitrogen fertilizers. This unfortunately creates many environmental, economical …

The first isolation of the rhizobial bacteria from the legume roots was done in 1888. Since
then a large number of scientists have made efforts to understand the molecular basis of …

The process by which free-living Rhizobium forms nitrogen-fixing nodules on the roots of
leguminous plants involves the induction and repression of a number of bacterial genes. To …

In order to maintain healthy growth, plants must extract a variety of elements from the soil in
which they grow. These elements include nitrogen and the so-called micro-nutrients (eg …

To provide the necessary information for strain improvement and the development of
competitive strains, characterization of some agronomically important inoculant Rhizobium …

Biological nitrogen fixation contributes an estimated 122 million tons of nitrogen per year to
agriculture. This occurs through natural infection of legume plants, namely clover, peas …

Legumes are very important food sources and therefore, the nitrogen fixing ability of legume-
rhizobia symbioses have great potential to improve crop yields. Biological nitrogen fixation …

In this study, Rhizobium leguminosarum infecting sympatrically distributed clovers native to
undisturbed meadows were characterized by the electrophoretic mobilities of nine metabolic …

The Rhizobium leguminosarum bv. trifolii Sym plasmid pRtr5a was transferred by
conjugation to R. meliloti strains deleted or mutated in the nod and fix genes, and also to a …