Time of stand establishment is a critical factor affecting
yields of winter wheat and barley in the fallow-crop rotation areas
of the Pacific Northwest. Farmers in this winter-rainfall region
are dependent on residual moisture in the seed zone for germination,
because significant precipitation does not usually occur until
after the...
An integrated study of growth, enzyme activity, and water potential of wheat seeds germinated under mild water stress conditions was conducted to observe the relationship among the three kinds of parameters studied. From the relationship, the cause(s) or mechanism(s) of water stress in plant growth may be enlightened. Two important...
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...
The influence of certain environmental and edaphic
factors on the germination and emergence of downy brome
(Bromus tectorum L.) was investigated in the laboratory. A
preliminary study was conducted to determine the osmotic
stability of mannitol and polyethylene glycol 20,000 (PEG)
solutions, which are commonly used to simulate water stress...
Two experiments were conducted to determine the effects of
moisture stress on physiological changes that occur during the vegetative
and reproductive stages of the wheat (Triticum aestivum L.)
plant, and to relate these effects to seed yield, quality and performance.
In a field experiment, different levels of moisture stress were...
Concern regarding the lack of genetic variability and the apparent yield plateau reached in wheat breeding have prompted this investigation. The systematic crossing of spring and winter wheat types which have evolved to form somewhat different gene pools, may provide a source of additional usable genetic variability for future yield...
Diclofop (2- [4 -(2, 4-dichlorophenoxy)phenoxy] propanoic
acid), formulated as the methyl ester, selectively kills
barnyardgrass [Echinochloa crus -galli (L.) Beauv.] in several
crops when applied postemergence. Studies were conducted
to determine the effect of soil moisture, barnyardgrass age, and site of exposure on control of barnyardgrass with diclofop. Soil moisture...
Spring grazing of annual ryegrass (Lolium multiflorum L.) seed
fields with sheep is a common practice in the Willamette Valley of
Oregon. However, the effect of grazing on seed yield in Oregon has
not previously been investigated. This experiment was designed to
determine the effects of duration of spring grazing...
Gas exchange, leaf area development, leaf anatomy and stomatal characteristics of four tall fescue selections differing in forage yield were examined to provide further insight into characteristics associated with yield differences of these selections. Winter-growing TFM 26 and TFM 16, the highest and lowest-yielding selections, respectively, and summer-growing selections TFK...
Previous work indicated a substantial heterotic expression for grain yield existed within winter/spring hybrids of barley, This research was a continuation for the comparison of the expression of heterosis within winter/spring hybrids to the heterotic effect produced among the winter and among the spring parents. The F₁ and F₂ progenies...