In most environments, ammonia (NH₃) is oxidized to nitrate (NO₃⁻) via the intermediate nitrite (NO₂⁻). This is a microbe-driven process involving phylogenetically distinct types of microorganisms, namely, ammonia-oxidizing bacteria (AOB) and Thaumarchaea (AOA), and nitrite-oxidizing bacteria (NOB). Nitrosomonas europaea and Nitrobacter winogradskyi are the best studied AOB and NOB, respectively,...
:
________________________________________________________________________________
PeterJ. Bottomley
In most environments, ammonia (NH3) is oxidized to nitrate (NO3-) via the
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...
Agronomic and microbiological studies were conducted on "Anchor" alfalfa (Medicago sativa L.) established from uninoculated seed on three Aridisols in central Oregon. Significant responses to 230 Kg N per ha (NH₄NO₃), which was applied in mid-April and after each first and second harvests, were observed in yield parameters of the...
Previous research had identified four serogroups of Rhizobium trifolii
indigenous to Abiqua soil (fine, mixed, mesic, Cumulic Ultic Haploxerolls).
Nodulation of subterranean clover (Trifolium, subterraneum L.) by two of the
serogroups, 6 and 36, was influenced by the application of CaC0₃ to the soil.
The studies described in this thesis...
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...
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...