In conventional cropping systems in the Willamette Valley, slow
establishing grass species, such as Kentucky bluegrass (Poapratensis L.) are planted in the spring and seed is not harvested
until the following year. Due to increasing annual production
costs, it is necessary to generate a cash return from each field
each...
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...
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...
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...
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....
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...
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...
Concerns about the genetic control and environmental influence
of various stages of development including the grain filling period,
and the relationship between early maturity and grain yield prompted
this study.
The experimental material consisted of two facultative and two
winter wheat cultivars. A dial!el cross, excluding reciprocals, was
also developed...