Chemicals are being sought that can control weeds in lettuce
under different environmental conditions, soil types and weed populations.
The extensive or repeated use of a herbicide may lead to important
changes in the weed population which call for new materials
that can take care of the modified situation.
In...
The objective of this study was to identify visual or easily
measured morphological characters associated with seed yield or its
components in a spaced-plant nursery of tall fescue (Festuca arundinacea
Schreb.). In 1977, 26 plant characteristics were observed on 210 plants
from seven different geographic regions of origin. Each origin...
Take-all root rot (caused by Gaeumannomyces graminis var.
tritici, Ggt) is one of the major diseases limiting winter wheat
yields in western Oregon. Losses caused by take-all (TA) can be
significantly reduced through crop management and fertilization
practices.
Results from field experiments in western Oregon show that the
use of...
Barley Yellow Dwarf Virus (BYDV) is a major disease of wheat. Unfortunately, unlike barley where the Yd2 gene provides adequate levels of resistance, the situation in wheat is more complex. This study was designed to provide information regarding: 1) evaluation of methods of measuring resistance among selected cultivars; 2) identification...
This investigation was motivated by the apparent increase in genetic
variability resulting from the systematic combining of gene pools
represented by winter and spring types of wheats.
It was the objective of this study to provide information regarding
the nature of this genetic variability for nine agronomic characters
in populations...
Field and growth chamber experiments were conducted to
determine chloride effects on the progress of stripe rust disease
caused by Puccinia striiformis West., and to investigate turgor
potential as the mechanism of the chloride effect.
Seven winter wheat (Triticum aestivum) cultivars were
grown in the field in 1982 and 1983...
Potash rate and source effects on tuber yield and quality
(hollow heart, size, and processing quality), and nutrient (K, Ca,
Mg, and C1) concentrations in petioles and tubers were evaluated in
three experiments, two in the Columbia Basin in Oregon (McDevitt and
Levy) and one in Central Oregon (Powell Butte)....
Antagonistic effects of Epicoccum purpurascens,
Aureobasidium pullulans, Trichoderma spp., and Botrytis
cinerea on establishment of Monilinia fructicola infections
in cherry and peach blossoms were assessed in field and mist
chamber studies. Conidia of each fungus were applied to
blossoms that were subsequently inoculated with conidia of
M fructicola. Mist chamber...
Cephalosporium stripe of wheat (Triticum aestivum),
caused by the soilborne fungus Cephalosporium gramineum,
results in significant yield reductions in dryland winter
wheat crops of the U.S. Pacific Northwest. The
development of resistant cultivars offers the best hope
for disease control. Breeding for resistance is hampered
by the long trial times...