Nodulation success by two indigenous Rhizobium
trifolii serogroups, 6 and 36, on subterranean clover
(Trifolium subterraneum L.) was affected by the addition
of phosphate to Abiqua soil (Ultic Haploxeroll). To
understand the impact of phosphorus nutrition on the
survival and nodulation characteristics of the two
serogroups, studies were carried out...
Although the biology of Bradyrhizobium has been studied for almost
one hundred years, virtually nothing is known about the ecology and genetic
variation in natural soil populations of this genus. The majority of
information has been obtained from studies of one species, Bradyrhizobium
japonicum, and the diversity within soil populations...
This thesis presents novel findings regarding
symbiotic, physiological, and antigenic characteristics of
representatives from an indigenous soil-borne population
of Rhizobium meliloti. Nodules were sampled from 'Vernal',
'Anchor', and 'Saranac' alfalfa, and the isolates analyzed
serologically. Rhizobium meliloti serogroup 31 was
identified as a dominant nodule occupant, with a greater
and...
In a series of greenhouse experiments, isolates representing serotypically
distinct subpopulations of Rhizobium leguminosarum bv. trifolii recovered from root
nodules of field-grown subclover Trifolium subterraneum cv. "Nangeela"), were
evaluated for their symbiotic effectiveness potential, their effect on regrowth
potential of subclover, and for their competitive abilities to form nodules. Isolates...
Complementary methods of strain identification were sought to
delineate the composition of the population of Rhizobium trifolii
found in nodules of Trifolium subterraneum L. when exposed to an
Abiqua silty clay loam (Cumulic Ultic Haploxeroll) containing a
resident population of R. trifolii. Sodium dodecyl sulfate
polyacrylamide gel electrophoresis (SDSPAGE) was...
The effect of carbon source, nitrogen source, and amino acid
starvation on the accumulation of guanosine tetraphosphate.and RNAand
protein synthesis in Rhizobium meliloti are described in this report.
An accumulation of ppGpp and a decrease in the rate of RNA and
protein synthesis were observed in response to nitrogen source...