Consulta: creatorFacets:"BUCKERIDGE,MARCOS S."
Registros recuperados: 3
Data/hora: 06/06/2024 00:28:08

Effect of abscisic acid on the mobilisation of galactomannan and embryo development of Sesbania virgata (Cav.) Pers. (Leguminosae - Faboideae)
Provedor de dados: 88
Autores: POTOMATI,ADRIANA; BUCKERIDGE,MARCOS S.
Galactomannans (GM) are storage cell wall polysaccharides present in endospermic seeds of legumes. They are thought to be storage polymers, since it has been observed for a few species (among them Sesbania virgata) that they are completely broken down after germination and their products are transferred to the growing embryo. We examined the effect of 10-4 M abscisic acid (ABA) on the degradation of galactomannan in isolated endosperms and intact seeds of S. virgata. We found that after seed germination the initial embryo growth was retarded. Ultrastructural analysis showed that the embryo is completely surrounded by an endosperm which displays very thick galactomannan-containing cell walls. Although an inhibitory effect has been observed on the increase...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Abscisic acid; Galactomannan; Seed; Leguminosae; Storage mobilisation.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042002000300006

Effects of light stress on the growth of the epiphytic orchid Cattleya forbesii Lindl. X Laelia tenebrosa Rolfe
Provedor de dados: 88
Autores: STANCATO,GIULIO C.; MAZZAFERA,PAULO; BUCKERIDGE,MARCOS S.
Considering the performance of CAM epiphytes under high levels of radiation or in shaded environments, with growth rate proportional to light intensity, the objective of this work was to evaluate the effects of long-term light stress on the growth of a Brazilian epiphytic orchid, Cattleya forbesii Lindl. X Laelia tenebrosa Rolfe. Two groups of plants were used in the first experiment, one under 90% (&lt;FONT FACE=Symbol&gt;@&lt;/FONT&gt; 1,650 µmol.m-2.s-1) of Photosynthetically Active Radiation (PAR) and the other maintained under 22.5% (&lt;FONT FACE=Symbol&gt;@&lt;/FONT&gt; 400 µmol.m-2.s-1). In the second experiment the diffusive resistance, transpiration rate and fluorescence levels were monitored for plants that were under 22.5% of PAR, under 90% and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Photoinhibition; Storage; Orchids; Pseudobulb.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042002000200011

Occurrence of xyloglucan containing protuberances in the storage cell walls of cotyledons of Hymenaea courbaril L.
Provedor de dados: 88
Autores: TINÉ,MARCO AURÉLIO SILVA; CORTELAZZO,ANGELO; BUCKERIDGE,MARCOS S.
Despite the suggestions of its pectic composition, no clear evidence for this has been presented. Here we show the occurrence of such a structure in walls of cells from cotyledons of Hymenaea courbariI L. These cells are known to accumulate large amounts of storage xyloglucan in the wall and, in this case, the protuberances seem to contain this storage polysaccharide rather than pectin. A hypothetical sequence of events leading from wall strands to protuberances was assembled based on scanning electron microscopy observations. On this basis, a tentative model for how polysaccharides are distributed into the wall, near the regions where protuberances are found, is proposed to explain the presence of storage xyloglucan in their composition.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Xyloglucan; Pectin; Cell wall; Protuberances; Hymenaea courbaril.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042000000400007