Erigeron decumbens var. decumbens, the Willamette Daisy, is endemic to the Willamette Valley of Oregon. This taxon is a Category 1 Candidate for listing under the federal Endangered Species Act (U.S. Fish and Wildlife Service 1990) and is listed as Endangered under Oregon state law. Herbarium records indicate that E....
Erigeron decumbens var. decumbens, the Willamette daisy, is known only from the Willamette Valley of Oregon. Herbarium records, from the 1800's until 1934, indicate that the Willamette daisy was once common and widely distributed throughout the Willamette Valley (Clark et al. 1993). However, between 1934 and 1980, this taxon was...
As the volume of genetic sequence data increases due to improved sequencing techniques and increased interest, the computational tools available to analyze the data are becoming inadequate. This thesis seeks to improve a few of the computational methods available to access and analyze data in the genetic sequence databases. The...
Phytophthora vignae, causal agent of stem and root
rot of cowpea (Vigna unguiculata), was reported for the
first time in Sri Lanka. The pathogen was found in cowpea
field soils from 3 of 5 geographic regions sampled. Only
one site however, had plants exhibiting disease symptoms.
Of the eight cowpea...
The septoria diseases of winter wheat are a limiting factor to wheat production in the Willamette Valley. This publication will describe the symptoms and development of the septoria diseases, including the influence of environmental conditions, the reactions of different cultivars to Septoria, the impact of Septoria on yield, and control...