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...
Increases in wheat production due to breeding may be reaching
a plateau. The application of N-fertilizer beyond optimum levels
leads to lodging and to an increase in tiller death. The use of
plant growth regulators (retardants) may be an answer for future
increases in production.
Experiments were conducted in 1983...
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...
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...
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...
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...
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...
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...
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...