Adventitious root formation can be inhibited in stem cuttings
of Pisum sativum L. (pea), an easy-to-root species, if the apical
and lateral buds are removed. Application of exogenous auxin to
the apical stump can replace the rooting stimulus produced by the
buds. Root number was reduced by 50 to 100%...
Water treatments were applied to young ponderosa pine trees in the Eastern Cascades, Oregon during the 2003 growing season, and shade treatments were applied during the 2003 and 2004 growing seasons to understand how photosynthesis and soil respiration, particularly the root/rhizosphere fraction (R[subscript rrh]), would respond to increased moisture availability...
The effects of ultraviolet (UV) irradiation on photosynthesis and
various partial reactions involving the individual photoreactions of
photosynthesis were examined. These reactions included photo-reduction in adapted green algae, Hill reaction, cyclic photophosphorylation,
the 520 nm absorbance change and variable-yield fluorescence.
The reactions were measured in spinach chloroplasts and
isolated chloroplasts...
A new photosystem-II mutant of the green alga Scenedesmus
obliquus D₃, strain PS-28, has been shown to lack a-tocopherol
(vitamin E). The photosynthetic activity of dark grown samples of
PS-28 is about 20% of the wild-type control. Culturing the mutant
at low light intentisites (10⁴ ergs/sec-cm ²) stimulates photosynthetic
activity...
The photosynthetic activities, the pigmentation and the chloroplast
membrane polypeptides of several mutants of the green alga, Scenedesmus
obliquus, with complete or limited deficiencies in the light-harvesting
complex of photosystem II are characterized and compared to those of the
normal phenotype.. The principal phenotype examined in this study, K0 -9,...
Manganese has been known to be essential for photosynthesis
for almost 30 years. Subsequent experimentation
indicated a definite function for manganese in oxygen evolution.
However, the mode of action of manganese and
further localization of its site of action have not been
determined.
Ten years ago it was demonstrated that...
Our view of phytoplankton has historically revolved around their inability to
control their location in space. The term phytoplankton itself underscores this
particular difference between phytoplankton and their sessile terrestrial counterparts.
Yet there are other differences between land plants and the phytoplankton that are
perhaps equally important, beyond this sessile-planktonic...
