The effects of some soil- and foliar-borne biotic factors on
grain yield and the components of yield were evaluated using five
winter wheat varieties sown at two dates. Within each planting date,
varieties were grown under four different combinations of two soil
treatments (fumigation and nonfumigation) and two foliar treatments...
A major factor limiting the efficiency of plant improvement programs is the lack of knowledge as to which parental combinations to make when working with quantitatively inherited traits. The primary objective of this study was to provide information regarding the use of combining ability analysis to predict which cross combinations...
Immature embryo explants taken eight days after anthesis were used
to establish callus cultures of spring barley. Two types of calli
were observed. A soft watery callus which produced a limited number
of shoots and a harder yellowish callus that gave rise to numerous
green primordia and shoots. Gamborg's B5...
The need to develop a shorter life cycle wheat cultivar which
would be more adapted to multiple cropping systems prompted this
study. Thus the following information was obtained.
Greatest variations in developmental patterns were found in the
stem elongation, booting, inflorescence emergence and anthesis for
five winter and five spring...
Seed yield in ryegrass (Lolium spp.) is the
product of the number of fertile tillers per unit area
and seed weight per spike at maturity. These
components of yield develop through a series of growth
stages beginning with tiller bud initiation and
finishing with seed filling. Environmental conditions
during plant...
Three stem rust Puccinia graminis graminicola, resistant sources of perennial ryegrass, Lolium perenne, 4A, 48A, and 77A, were crossed in a partial diallel design with one susceptible source, MP-2, resulting in six crosses excluding reciprocals. The F1's and cloned parental populations were inoculated in the field and rated on a...
This thesis consists of four chapters. Literature is
reviewed in Chapter 1. Chapter 2 describes an addition
series experiment to determine the influence of species
density and proportion on vegetative and reproductive yield
of spring wheat and Lolium multiflorum. Chapter 3 consists
of a growth analysis experiment to determine whether...
Stand establishment plays a significant role in the development
and yield of winter wheat (Triticum aestivum L.). Availability of
soil moisture to the germinating seed is one of the most critical
factors affecting stand establishment. Water injection is a method
of applying supplemental moisture to the soil in direct contact...
Some biochemical activities in embryo or seedling of
germinating rice (Oryza Sativa L.) seed were studied to explain the
effects of suboptimum (20 C), optimum (30 C), and supraoptimum (40 C)
temperatures on seed germination and seedling growth. It was observed
that 40 C slightly speeded up seed germination but...
Glyphosate (N-(phosphonomethyl)glycine) is an effective
foliar-applied herbicide with broad-spectrum activity. Greenhouse
and laboratory experiments were conducted to determine the
importance of soil moisture, autoclaved soil, soil type, sphagnum
peat, soil pH, added phosphorus, and plant residues on crop
establishment and growth when glyphosate was applied before
emergence of the crop....
Four winter wheat cultivars, Bezostaya, Maris-Hobbit, Roussalka
and Stephens, selected on the basis of the diversity of their pedigree and phenotype, were planted at Hyslop Experiment Station near
Corvallis in Western Oregon to study their performance at three
different row spacings (10, 16 and 24 cm), three seeding rates
(100,...
Hard Fescue (Festuca longifolia Thuill.) has potential for in
creased turf use but does not respond well to normal seed production
management practices in Oregon. Field burning (the normal residue
management practice) results in reduced seed yields in commercial hard
fescue seed production fields but stimulates seed production in Chewings...
The semi-arid regions of the Pacific Northwest are
characterized by a high degree of annual temperature and
precipitation variation. As a result of this climatic
variation, dryland nitrogen fertilizer trials on fallow-
,wheat rotations typically demonstrate a variable response.
Wheat growers in the area must not only cope with this...
A field study was conducted in 1978 and 1979 at the Hyslop Crop
Science Field Laboratory near Corvallis, Oregon, to determine the optimum
capsule harvest date of Papaver bracteatum Lind. for thebaine yield
and oil yield, while maintaining an acceptable percentage of seed germination.
Accessions PI 383309 and PI 381607...
Dryland winter wheat in eastern Oregon is usually subjected to
water stress several times during the growing period. Moreover, the
last three months of growth period depend strongly on the available
soil water. The fertility level, stage of growth, availability of
soil water and climatic conditions all interact to determine...
The effect of four basic liquid fertilizers: Solution 32, 10-34-0-.9, Thio-Sul, and Potash solution; and one commercial liquid fertilizer, Feast 9-18-9, on germination, emergence, and seedling growth of wheat (Triticum aestivum L.) were evaluated under laboratory, greenhouse, and field conditions. Experiments included: 1) preliminary study of basic fertilizer sources to...
Meadowfoam (Limnanthes alba Benth.), an open-pollinated herbaceous
winter annual, is adapted to Mediterranean climates and produces
a seed oil with industrial uses. Seed yield in meadowfoam is
partially determined by the number of seeds produced per flower. The
flower is protandrous with the stigmata becoming receptive 1-3 days
after anther...
This study was undertaken to better understand plant characteristics
related to high and low forage yield in tall fescue selections
as affected by temperature. Dry matter distribution into yield components
in three different temperature regimes was evaluated. Root
growth, dark respiration and nutrient concentration were also examined.
The four diverse...
Soil-related problems common to Oregon farmers are
erosion, compaction, organic matter depletion, and
nutrient loss. High costs of fertilizer, fuel, and weed
control are additional management problems. Growing a
secondary crop as a living mulch with a primary crop may
ease some of these problems.
Sweet corn production in Oregon...
Oregon sweet corn growers face high fertilizer, fuel
and weed control costs; soil compaction, erosion, organic
matter and nutrient depletion; and difficult equipment
operations in muddy fields. An alternative production
system might ease some of these problems.
Testing was begun to evaluate a living-mulch
cropping system for sweet corn (Zea...
Napropamide [2-(alpha-naphthoxyl)-N,N-diethylpropionamide], a
preemergence herbicide, is widely used in the United States on a
variety of tree fruits, nut crops, vegetables, and mint for annual
grass and broadleaf weed control. When napropamide has been left on
the soil surface without incorporation through irrigation or mechanical means, inconsistent results have been...
Experiments were conducted to determine: (1) effects of pretransplant
stolon formation on performance of potato transplants in
the field and greenhouse; (2) effects of parent plant nodal position
on productivity of rooted nodal cuttings; and (3) relationships
between photoperiod and stolon formation.
The effects of early stolon formation on Russet...
Orchardgrass and tall fescue seed crops are commonly springplanted
in Oregon, but do not produce a marketable crop during the first
growing season. Establishing orchardgrass and tall fescue with cereal
companion crops would provide income during the seeding year and could
increase seed production profits. This study was conducted to...
The semi-arid dryland wheat-producing areas of the Pacific Northwest are characterized by cool, moist winters and dry, hot summers. The amount of annual precipitation is generally quite variable and inadequate for annual cropping. Where soil depth is adequate, the predominant loessal soils generally supply sufficient moisture for small grain production...
The herbicide rate required to reduce growth by 50% (GR₅₀) of 11
cultivars of red fesue (Festuca rubra L. and F. rubra ssp. commutata)
and for four cultivars of bentgrass (Agrostis tenuis Sibth. and A.
stolonifera L. var. palustris) to sethoxydim (2-[1-(ethoxyimino)
butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one) was
determined in greenhouse and laboratory experiments....
Volunteer winter wheat (Triticum aestivum 'Daws')
severely suppressed growth of fall-planted alfalfa
(Medicago sativa (L.) 'Vernal') seedlings. Wheat
competition began soon after alfalfa emerged and continued
until the first forage harvest the following May. Alfalfa
yield at the first cutting was reduced by 1% for each day
volunteer wheat was...
Seed yield in perennial ryegrass is the product of yield components
that develop during the life of the plant. Crop yield potential is
defined by the number of fertile tillers, spikelets per spike, and
florets per spikelet. It has been shown that perennial ryegrass
realizes only a small percentage of...
A seed maturation study was conducted to determine the earliest
date seed of subterranean clover (Trifolium subterraneum L.) may be
safely harvested without reduction in yield or seed quality. In 1981
and 1982, seed and bur weight, seed and bur moisture content, germination and seedling vigor were studied to determine...
Wild proso millet (Panicum miliaceum L.) is a serious weed
recently infesting sweet corn fields in the Willamette Valley of
western Oregon. Field and greenhouse experiments were conducted to
determine the importance of seed depth in the position of the growing
point of wild proso millet seedlings and in the...
The number of varieties of ryegrass (Lolium spp.) has increased greatly in recent years. An accurate and rapid laboratory technique to identify these varieties would benefit the consumer as well as protect an organization's Plant Variety Protection rights. There is also a need for a technique to complement the seedling...
Response from nitrogen and chloride fertilization was measured
in field experiments on winter wheat (Triticum aestivum L. Em.
Thell. var. 'Stephens' and 'Yamhill') grown in western Oregon in an
environment with a range of susceptibility to take-all root rot
(Gaumannomyces graminis var. tritici Walker). Cropping sequences
and expected disease severity...
Downy brome (Bromus tectorum. L.), a serious grass weed in eastern Oregon can be partially controlled in wheat by metribuzin [4-amino-6-tertbutyl- 3-(methylthio)-as triazin -5(4H)-one]. However, cultivars of many crops Lave been reported to differ in their level of tolerance to metribuzin. This lack of tolerance has led to the investigation...
Marah oreganus, a perennial, belongs to the Cucurbitaceae family
and it is commonly known as wild cucumber. In the past, this plant
grew along fence rows, but now wild cucumber has become a weed
problem in perennial grass seed fields of western Oregon. Several
research studies were conducted to examine...
This study was undertaken to see if a method of handling
segregating populations could be employed which combined the positive
attributes of the traditional pedigree and-bulk methods. Derived F₅
lines from the pedigree, bulk, and what is identified as a modified
bulk method, were obtained from three winter wheat crosses....
The response to glyphosate [N-(phosphonomethyl) glycine] of two
dodder species Cuscuta campestris Yuncker (field dodder) and Cuscuta
indecora Chiosy (largeseed dodder) parasitizing alfalfa (Medicago
sativa L.) was compared. In the absence of glyphosate, alfalfa was
killed or severely injured by parasitism from uncontrolled dodder.
Results of field experiments in which...
Farmers and researchers are aware of spatial variation in
grain yield within farms or fields. Fertilizer management may be
improved if techniques can be developed to identify grain yield
variations in wheat fields. Aerial color infrared (CIR)
photography was used to identify winter wheat (Triticum aestivum
L.) canopy biomass variability...
Ten wheat crosses (four winter x spring and six winter x winter)
involving F₃ and F₄ generations and their respective winter parents
were used to determine whether the early generation selection would
be effective for kernel hardness and grain protein content. In
1980, twenty individual F₂ plants were selected with...
Concerns about the possible reciprocal differences resulting from
systematic crossings of winter and spring wheat gene pools prompted
this investigation. If traits can be improved by simply reversing the
direction of a cross, then identification of the best female parent in
a cross would be helpful for breeding programs.
Two...
Grain yield and grain protein are often negatively associated in
wheat. When yield increases and grain protein decreases, there can be
an adverse effect on the milling and baking quality if the desired end
product is bread flour. It has been suggested that this inverse
association is the result of...
Four isogenic lines possessing different combinations of height
reducing genes Rht₁ and Rht₂ from 'Norin 10' were crossed to a short
stature, early maturing, septoria susceptible cultivar identified as the
'Tibet Dwarf'. The isogenic lines originated from the backcross
population of 'Itana'/3/'Norin 10'/'Brevor 14'//6*'Itana'. Parents, F₁
and F₂ generations provided...
During physiological ageing of seed potatoes, the stored tuber
undergoes certain biochemical changes which cause the breaking of
dormancy and the initiation of bud growth. The ageing process can
be manipulated through storage temperature and duration. Higher
temperatures usually accelerate seed tuber ageing. In order to
define the process of...
Rate of emergence is an important character for stand
establishment. Ability of wheat seeds to germinate and
emerge rapidly under different climatic conditions may be
regulated by physical and/or physiological characteristics.
Seeds of 26 wheat varieties representing five classes
were produced in two different environments (Moro and Corvallis,
OR). Seed...
Field studies were started at Hyslop Farm, Corvallis,
Oregon in 1984 to determine the soil persistence of the
herbicide clopyralid (3,6-dichloropicolinic acid) under
cropping situations. The herbicide was sprayed on bare soil
at the proposed use rate of 0.14 kg/ha in the spring and on
the same plots at a...
The objective of this study was to compare three genetically
different groups of winter wheat for their grain yield. Experimental
material consisted of parental lines grown in pure stands, hybrids, and
1:1 mixtures of the parental combinations. Three sites were employed to
evaluate possible interactions between the different groups across...
Rapid tiller and root production can improve seedling survival and
benefit stand establishment of perennial ryegrass (Lolium perenne L.)
in commercial seed fields. Environmental conditions after establishment
and inherent morphological factors combine to reduce the commercially
harvested yield below the theoretical potential yield.
These studies were conducted to determine if...
Seed vigor tests have been developed to evaluate the relative ability of seed lots to produce stands of seedlings in the field. Some workers have suggested the possibility of differentiating vigor levels by germinating seeds under osmotic stress, but have not conducted field trials to evaluate the usefulness of the...
A series of experiments were conducted from 1983 to 1985 to
determine the effects of dinoseb [2-(1-methylpropyl)-4,6-dinitrophenol]
on winter wheat (Triticum aestivum L. em Thell) yields. Field trials
on dinoseb timing and dinoseb plus supplemental pesticides were
established in an effort to elucidate the possible factors involved in
the yield...
Hard red winter wheat has the potential to be an alternative crop
in the Pacific Northwest, however percent grain nitrogen has been
unacceptably low and grain yields have been about only 80% of soft white
winter wheat. During the late spring and the summer months there is
usually little rainfall,...
Nitrogen fertilization of seedling legumes is a controversial practice intended to provide N to the plant during periods when seed N, soil N, and N₂ fixation may not meet plant requirements; eg. prenodulation, postharvest, or in the event of an inoculation failure. Field experiments were conducted in 3 consecutive years...
Meadowfoam has been identified as a potential oilseed crop for
production on poorly drained soils in areas with cool, moist winters.
The effects of N fertilizer on meadowfoam (Limnanthes alba Benth.)
have been studied in Oregon and Maryland, but the results have not
been consistent with respect to the effects...
The effects of different fallow moisture levels and tillage
systems on the amount of nitrate-nitrogen accumulation in the 0-30 cm
soil profile were studied.
Fallow moisture treatments simulating typical dry, normal and
wet precipitation cycles were established on trial plots.
Data were obtained for nitrate-nitrogen, soil moisture and
nitrogen mineralization...
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...
The nature of inheritance and possible associations for traits
influencing earliness and grain yield were investigated using a four
parent diallel of winter and spring wheat cultivars.
More genetic variability was observed for the traits measured in
segregating populations resulting from crosses between winter and spring
type wheats in contrast...
This study was conducted to investigate the possible contamination
of foreign pollen at different stages of a wheat breeding
program. These included spaced planted F₂ segregating populations,
replicated yield trials and seed multiplication. The experimental
wheat materials consisted of four different F₂ populations, four
cultivars and two experimental lines.
Two...
Influence of abiotic and biotic factors were examined in selected
winter wheats previously identified as representing a range of
responses to septoria infection. In the greenhouse two and three
inoculations identified resistance when disease severity was assessed
either for the top four leaves or the flag leaf respectively. Kernel
number...
Models of weed communities aid in the development of
weed management strategies and elucidate the processes
and mechanisms that regulate plant populations and
communities. A conceptual weed community model was
developed to organize key regulatory life-history
processes. Specific investigations focused on the
processes of plant growth and competition, and
relationships...
An understanding of the effect of environment on
phyllochron (degree-days between two successive leaves) is
necessary to model cereal crop canopy growth. This study
was designed to investigate the relationships of phyllochron
to temperatures and daylengths in winter wheat (Triticum
aestivum L.) and spring barley (Hordeum vulgare L.). A
series...
The focus of this study was to determine if S₁ family recurrent
selection might be successfully used for barley improvement.
Objectives were: 1) to identify suitable methods of evaluating grain
yield in small plots, 2) to study the effects of intermating on mean
values and variances of selected agronomic characters,...
Lodging in cereals can cause significant decreases in yield. It
is both a problem in susceptible cereal cultivars with a tall-stemmed,
weak-strawed growing habit and in lodging-resistant
cereal cultivars when they are grown under high-nitrogen, high-moisture
regimes. Plant growth regulators (PGR's) are chemical
growth retardants that offer a method of...
There is an increasing need for development of laboratory
identification procedures for purposes of plant variety protection, seed certification, quality control and consumer protection. In the past there were fewer commercial varieties and field
testing methods based on morphological differences were used satisfactorily. These tests require several months to complete...
Living mulches are vegetative covers that can grow in association with row crops and may prevent soil erosion and suppress weeds. Crop reduction from association with the living mulch is a frequent problem with this cultural practice. The interference between a white clover (Trifolium repens L. "New Zealand") living mulch...
Parents and progeny populations from a cross of 'Stephens'x 'Tibet dwarf' were grown in a spaced-planted experiment to obtain information concerning the nature of inheritance and possible associations between grain yield and the components of yield. Agronomic traits measured on an individual plant basis were: heading date, days to maturity,...
The interference of barnyardgrass (Echinochloa crusgalli),
pigweed (Amaranthus retroflexus),downy brome (Bromus
tectorum),and tumble mustard (Sisymbrium altissimum)
with alfalfa was studied. Alfalfa was seeded with each of
the four weeds on August 14 and September 15, 1981, and on
April 13, 1982. Alfalfa also was seeded on August 27, 1981,
with...
Previous studies have shown loss of ethofumesate activity when
the herbicide was applied to dry soil (2% w/w moisture content) in
both field and greenhouse studies, even when rainfall or irrigation
was received within a few days. Laboratory studies were conducted to
determine the mechanism for this activity loss. Dry...
Parental lines, Fi's and segregating populations (F₂, F₃ and BC's) including reciprocals were evaluated under field conditions to determine if genetic resistance per se exists for Septoria Leaf Blotch in a selected winter wheat cross. The experiment was conducted over a three year period with both natural infection and artificial...
Bunt or stinking smut is a major disease of wheat. In the U.S.
common bunt, Tilletia caries (DC) Tul. and T. foetida (Wallr) Liro,
is a threat to wheat production in the Pacific Northwest. Screening
trials conducted by USDA Cereal Investigations Project in Oregon,
from 1955-1980, revealed that a number...
Differential grain yield response of two winter wheat cultivars
('Yamhill' and'McDermid) when grown on acid soils prompted this investigation.
Root samples were taken at two soil depths at late
tillering and anthesis from plots established on an acid nonpareil
soil in Douglas County, Oregon. The soil pH was 5.2-5.3 and...
This investigation was conducted to provide information regarding
1) the relationship between the nitrogen percentage in the vegetative
tissue of wheat and barley at various growth stages with grain protein
and 2) to evaluate the possible association between grain yield
and grain protein as influenced by different cultivars, nitrogen
levels...
To study the grain filling traits in wheat, two winter cultivars
and four spring cultivars were selected. The resulting Fl, F2, F3 and
backcrosses were tested. The following measurements were made:
a) Visual traits for physiological maturity (PM),
b) Grain dry weight accumulation,
c) Regression models for grain filling period,...
A great potential for increasing upland rice production exists in
the savanna soils of Colombia. These vast areas are currently
underutilized. However, they have good soil structure, flat
topography, coupled with sufficient and well distributed rainfall,
making savanna soils ideal for upland rice cropping system. The major
constraints to upland...
Kentucky bluegrass (Poa pratensis L.) cultivars are known to differ quantitatively in their photothermal floral inductive requirements. The extent to which these requirements are met influences the potential for subsequent panicle exsertion. A better understanding of the inductive requirements as they vary among cultivars would aid in the selection and...
Field study with 5 tall fescue genotypes treated at the vegetative
growth stage, with 0, 0.28, 0.56, and 0.84 kg/ha of mefluidide
was initiated in July, 1980. The regrowth of these plants were again
treated at the booting growth stage in April, 1981, with the same
rates of mefluidide as...
Giant hills may be classified as semi-giant, giant, or super-giant
depending on the degree of the variation. All are large,
vigorous, profusely flowering plants with characteristically poor
tuber shape, although some giant hills may have smooth tubers.
Thirteen of the fifteen Russet Burbank giant hill selections grown
in Con/all is,...
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...
Laboratory and field studies were conducted at Pendleton, Oregon, during 1983 and 1984 to evaluate germination and growth characteristics of five jointed goatgrass (Aegilops cylindrica Host) accessions collected from sites in Echo, Ione, Pendleton, Condon, and Elgin, Oregon. Spikelets were germinated for 27 days at room (23 +̲ 2 C)...
Meadowfoam (Limnanthes spp.) is a potential oil seed
crop being developed for commercial production in the
Willamette Valley. The seeds are characterized by poor
germination at warm temperatures. It would be desirable
to overcome this temperature-related dormancy problem so
that better stand establishment could be realized from
early fall planting....
To increase efficiency of seed production, it is important to
understand the effects of nitrogen (N) fertilizer rate and time of
application. In particular, the effects on floret fertility should
be examined since only a small proportion of florets actually produce harvestable seed. For these reasons, experiments were conducted in...
The objective of this investigation was to evaluate the
possibility of developing high yielding wheat cultivars whose flour
would result in acceptable loaf volumes for non-traditional bread
wheat growing areas. Spring wheat germplasm employed included high
protein hexaploid derivatives from Triticum dicoccoides, and
selections from Argentina with good bread milling...
Equipment for strip-till planting is under development in wheat-fallow
rotations in the Columbia Basin of Oregon. This involves the
absence of tillage during the fallow season. At planting time, the
strip-till planter creates a narrow band into which the wheat seed is
placed. The area between the rows is undisturbed...
Germination of meadowfoam (Limnanthes alba Benth.) seed is inhibited by warm soil temperatures. This has led to recommendations for planting from early to mid-October when soil temperatures are below about 15°C. Objective data on the effects of planting date on stand establishment and yield are not available. These studies were...
Weedy rye (Secale spp.) is a weed in the winter-wheat- growing
regions in the Pacific Northwest and surrounding regions. Ethiazin
(4-amino-6-(1,1-dimethylethyl)-3- (ehtylthio)-1,2,4-triazine-5 (4H)-one)
has shown selective control of weedy rye in the cultivar 'Stephens',
(Triticum aestivum). Field, greenhouse, and outdoor pot experiments
were conducted to determine factors influencing selectivity.
Field...
A study of populations characteristics of T. turgidum ssp.
carthlicum and T. aestivum ssp. carthlicoides was completed using
numerical analysis. A sample of 74 accessions of ssp. carthlicum
and 20 of ssp. carthlicoides were scored for 46 characters. It was
established that three morphological distinguishable groups of ssp.
carthlicum can...
Centuries of continuous grain cropping in northern Africa have
reduced N levels in soils to a degree such that agricultural production
is now largely dependent upon nitrogen fertilizer. Through the
identification of highly effective legume and Rhizobium strain combinations,
the production of protein-rich livestock forage and green
manure can be...
Hill plots and near infrared reflectance (NIR) spectroscopy were
investigated as breeding tools to facilitate doubled haploid recurrent
selection for malting quality characters in spring barley. Main
objectives of this research were to i) compare hill and row plot
expression of agronomic and malting quality traits in an array of...
Agrobacterium rhizogenes has been shown to cause root
proliferation and increased water use efficiency in
certain woody dicots. Root proliferation may be desirable
in herbaceous legumes as a means of increasing potential
sites for infection by Rhizobium species and subsequent
nodulation and nitrogen fixation. Thus, A. rhizogenes was
used to...