Field microplot studies conducted over two seasons
(1982-1984) evaluated the influence of four physically and
chemically diverse soils collected from Pacific Northwest
wheat fields on the incidence of dwarf bunt of winter
wheat caused by Tilletia controversa Kuhn. These soils
were placed at Flora and Pendleton, Oregon to determine
the...
Prior to 2005, ammonia oxidation, the first step of nitrification, was thought mediated mainly by ammonia-oxidizing bacteria (AOB). However, the discovery of Thaumarchaeota carrying the genes coding for the ammonia monooxygenase (AMO) enzyme led to the discovery that ammonia-oxidizing archaea (AOA) also contribute to nitrification. Despite the uptick in studies...
Ectomycorrhizal fungi (EmF) form symbioses with trees. These symbioses profoundly influence forest ecology. Certain EmF form specialized profusions of hyphae, known as ectomycorrhizal fungal mats (mats) which are visible to the naked eye, alter forest soil biogeochemistry, substantially contribute to soil microbial biomass/respiration and support unique microbial communities. Piloderma and...
This thesis explores the factors limiting the alkene substrate range of the vinyl chloride (VC)-utilizing bacteria, and describes a method for measuring VC transformation in situ. Vinyl fluoride (VF) was evaluated as a surrogate for monitoring aerobic VC-transformation utilizing three isolates, Mycobacterium EE13a, Mycobacterium JS60 and Nocardioides JS614. JS614 grew...
This dissertation consists of a general introduction, three research manuscripts, and general conclusions regarding the mapping of quantitative trait loci (QTLs) for sustainability traits in the Triticeae Coordinated Agricultural Project (TCAP) facultative/winter 6-rowed elite malting barley genome-wide association studies (GWAS) mapping panel, the TCAP FAC-WIN6. The first research manuscript, a...
Dried cattail and bulrush plant pieces in mesh bags were incubated in the
constructed wetland treating Pope & Talbot pulp mill effluent. Two ponds
planted with each species and two depth ranges in each pond were chosen, to
determine decomposition rates. Bags were withdrawn and analyzed at five time
points...
This research focused on anaerobic transformation of trichloroethene (TCE), a
groundwater contaminant. The mixed anaerobic Evanite culture (EV) was studied to determine community behavior and composition responses to different electron donors and chloroethene electron acceptors. The potential toxicity from high concentrations of TCE and its daughter product cis-1,2-dichloroethene (cDCE) was...
The objective of this study was to examine the variation among ammonia-oxidizing and denitrifying communities in soils of a natural Fennoscandian boreal forest and of a forest with a long history of fertilization with different levels of nitrogen (N), and to examine whether there are any changes in the microbial...
The objectives of this thesis were to examine the links between soil microbial community composition and function using the nitrogen (N) cycle as a model for these interactions and to assess the impact of environmental factors such as microclimate, vegetation type, and nutrient availability on microbial diversity and N transformations...