Concerns regarding the most effective means of evaluating
segregating generations of spring barley prompted this investigation. Three methods of selection were considered: bulk, pedigree, and single seed descent. F₆ lines derived by each method
were grown in a replicated yield trial. The effectiveness of each
method was measured in terms...
Responses to two cycles of mass selection for heading date,
followed by selfing or intermating, were studied in two diverse
winter wheat (Triticum aestivum L. em. Thell) crosses. Selection
was bidirectional, resulting in early and late populations for
each mating system, cycle, and cross. The influence of mass
selection for...
The major objective of this study was to determine why certain
winter wheat cultivars, when hybridized, will produce a greater proportion
of desirable plants in subsequent, segregating generations.
Three winter wheat parents were chosen as the experimental material,
based on their known performance as parents. Yamhill and
Pullman Selection 101...
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...
Forty-six morphological characters were used in a study of Triticum turgidum ssp. carthlicum (2n = 28) and specimens of carthlicum-like forms of Triticum aestivum ssp. vulgare (2n = 42). The morphological variation patterns within these groups were examined using stepwise discriminant analysis. These results indicate that specimens studied could be...
Three chemicals SD 55446, SD 55447 and WL 84245 were found to
induce male sterility in cultivars of wheat or triticale. Both SD 55446
and SD 55447 when applied at a concentration of 0.896 kg/ha resulted
in 90% male sterility. However, SD 55447 caused female sterility at
the same concentration...
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...
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...
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...
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...