Entomopathogenic fungi are cosmopolitan microbial pathogens that cause fungous diseases in a wide range of insects via spore infection. Due to their natural enemy status, they have tremendous potential for use as microbial control agents against insect pests, especially subterranean pests for which few management options are available. The clover...
Bees provide critical pollination services to diverse agricultural crops, native plants and trees. Globally, there are reports of bee declines which have been attributed to diseases, exposure to pesticides and changes in land use that are believed to have led to a reduction in foraging resources and nesting habitats for...
Bumble bees provide vital pollination services in both native and agricultural landscapes. However, in recent years, bumble bee populations have experienced global population declines. The primary causes of these declines have been attributed to the environmental impacts of pathogens, pesticide use and habitat fragmentation. While research has examined the impacts...
Epichloë typhina (Ascomycetes: Clavicipitaceae) is an endophytic fungus that
infects perennial Pooid grasses and is the causal agent of choke disease. It is endemic
to Europe and was inadvertently introduced into orchardgrass seed production fields in
western Oregon. Choke disease, which was first recorded in Oregon in 1996, currently
infects...
In cranberry (Vaccinium macrocarpon Aiton) cultivation, farmers typically rent colonies of honey bee (Apis mellifera) for pollination. However, the efficiency of this bee at pollinating cranberries in Oregon, as in other regions, is questionable. Bumble bees (Bombus sp.) are reportedly effective in other regions, but their impact in Oregon is...
Bumble bees (Hymenoptera: Apidae) are important native pollinators in wild and agricultural systems, and are one of the few groups of native bees commercially bred for use in the pollination of a range of crops. In recent years, declines in bumble bees have been reported globally. One factor implicated in...
A two-dimensional numerical mesoscale model, which ic1udes
radiative and turbulent transfers, has been constructed to study the
formation, development and dissipation of coastal stratus cloud
under an inversion. In the model, the delta-Eddington and emissivity
approximations are used for the solar and thermal radiative
transfers, respectively. K-theory parameterization is adopted...
Bilinear systems, encountered in many important applications of engineering, biological and socio-economic systems, represent the logical step in complexity between the linear systems which are inadequate in the modeling of various dynamic processes and the difficult realm of nonlinear systems. This dissertation studies two functional expansions in bilinear system analysis-...
Temporal variations in surface ground temperature impart a signal to the subsurface thermal regime that is captured in borehole temperature-depth profiles. Seventy temperature-depth profiles in India, located between 12° and 28°N, are analyzed to infer past changes in ground temperature. These profiles exhibit predominantly positive anomalous temperatures relative to the...
The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. Uncertainty about bee populations at global and local scales has prompted research and general interest in conservation of bee diversity....