A screening of Castanea sativa scions for grafting for the presence of endophytes showed that the opportunistic fungal pathogen Gnomoniopsis smithogilvyi was the most abundant member of the endophytic flora. This fungus is known as a pathogen affecting chestnut fruits in Italy and Australia. Here, we present evidence that it causes cankers very similar to the ones due to Cryphonectria parasitica infection on twigs and scions of chestnut trees.
View Article and Find Full Text PDFGrowth hormone-responsive and nucleoside triphosphate-dependent enlargement of inside-out vesicles of plasma membranes from soybeans prepared by aqueous two-phase partition and everted by freezing and thawing has been achieved in a cell-free system. In the presence of 100 microM ATP in 40 mM HEPES buffer, pH 7, enlargement of isolated plasma membrane vesicles was accelerated by the synthetic plant growth factor, 2,4-dichlorophenoxyacetic acid (2,4-D), compared to ATP alone, 2,4-D alone or no additions. After 20 min with 1 microM 2,4-D, vesicles increased in diameter, 20% on average.
View Article and Find Full Text PDFA quantitative cytochemical study was made of fructokinase, glucokinase, and fructokinase (both PFK-ATP and PFK-PP + F-2:6-P) activities in shoot apices of 4-week old Spinacia oleracea. The rates of activity of these enzymes in the central zone of the shoot apex of plants kept on a short day regime were compared with those from plants transferred from a range of timing up to 24 h to a continuous light regime when floral induction occurred. A mechanism is suggested explaining how no measurable change in activities of the enzymes assayed could still account for the availability of adequate levels G-6-P as substrate for pentose pathway activity which is almost doubled early on in cells of the central zone of shoot apices induced to flower.
View Article and Find Full Text PDFA procedure is described whereby highly purified fractions of plasma membrane and tonoplast were isolated from hypocotyls of dark-grown soybean (Glycine max L. var Wayne) by the technique of preparative free-flow electrophoresis. Fractions migrating the slowest toward the anode were enriched in thick (10 nanometers) membranes identified as plasma membranes based on ability to bind N-1-naphthylphthalamic acid (NPA), glucan synthetase-II, and K(+)-stimulated, vanadate-inhibited Mg(2+) ATPase, reaction with phosphotungstic acid at low pH on electron microscope sections, and morphological evaluations.
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