A study of the Prince of Wales Island alpine areas was undertaken
to determine what species occur in the region and to describe
plant communities making up the alpine vegetation.
For one month in 1972, specimens were collected and 78 micro-plots
were analyzed for cover, frequency and constancy data. Three...
Under defined cultural conditions, zygotes of the brown alga
Fucus distichus L. Powell divide synchronously to form two-celled
embryos at approximately 24 hours after fertilization. These two
cells differ from one another in gross morphology, ultrastructure,
cytochemistry, and developmental fate. Cytochemical staining and
autoradiography indicated that a sulfated polysaccharide was...
The developmental cytology of the elaiosome of
Dicentra formosa (Andr.)Walp. was investigated from the
time of initial differentiation until complete maturation.
Light and transmission electron microscopy studies
showed that the elaiosome becomes differentiated from
epidermal tissue in the prefertilized ovule. At this time
the cells are characterized by their large...
The teliospore of Tilletia caries germinates to produce a promycelium
with a whorl of primary sporidia at its tip. The time between
emergence of the promycelium and the development of primary sporidia
averaged 2.3 h. Fusion between compatible sporidia occurred within
an additional 3.8 h. Primary sporidia appeared to be...
The ability of N,N'-diphenylurea (DPU) to substitute for cytokininactive
adenine derivatives in promoting callus growth of Phaseolus lunatus
and Nicotiana tabacum has been examined. In general, DPU stimulated
callus growth of P. lunatus at high concentrations and the growth of
most callus tissues was irregular, while the response of tobacco...
Black Butte presents a unique natural laboratory for ecological
study. It is a volcanic cone of uniform configuration located in the
rain shadow on the east flank of the Oregon Cascades. Soils are of
very recent origin with no obvious development of horizons.
Physical and chemical analysis revealed little dissimilarity...