Consulta: subjectFacets:"Recalcitrance"
Registros recuperados: 7
Data/hora: 02/06/2024 17:31:22

Desiccation effects on germination and vigor of King palm seeds
Provedor de dados: 75
Autores: Martins,Cibele C.; Bovi,Marilene L. A.; Nakagawa,João.
The desiccation tolerance of Archontophoenix alexandrae (Wendl. &amp;amp; Drude) seeds was determined and the most sensitive vigor test for assessing seed deterioration of this species was identified. Mature fruits were harvested in the palm collection of the Instituto Agronomico in Campinas, Brazil. Depulped fruits were transported in impermeable packages to the Faculdade de Agronomia in Botucatu, where the seeds were dried. As the seed moisture decreased, germination, seedling length, electrical conductivity and moisture were measured. The seeds of A. alexandrae are recalcitrant, with high germination percentage (over 67%) when undried (47% seed moisture). Lowering seed moisture below 31.5% reduced the germination rate significantly (&lt;52.5%). Total...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Archontophoenix alexandrae; Alexandra palm; Seed deterioration; Electrical conductivity; Recalcitrance; Desiccation tolerance; Critical moisture; Lethal moisture.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362003000100019

Genetics evaluation of minicuttings rooting of Eucalyptus cloeziana provenance
Provedor de dados: 190
Autores: Oliveira, Leandro Silva; Dias, Poliana Coqueiro; Almeida, Marcílio de.
Cloning of superior genotypes is presented as an alternative to increase forest productivity, because it allows capturing the genetic gains (additives and non-additives) from forest breeding. Early selection based on characteristics related to adventitious rooting may be important for breeding programs for recalcitrant species, like Eucalyptus cloeziana F. Muell. The objective of this work was to perform the genetic evaluation of E. cloeziana individuals based on adventitious rooting. The genetic control of adventitious rooting of 52 E. cloeziana trees was analyzed by variance components estimation and predicts breeding values. We used REML/BLUP procedure (estimation of variance components - Reml and prediction of breeding values - Blub). The variables...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Herdability; Recalcitrance; Propagation; Clonal selection Engenharia Florestal; Melhoramento Florestal Herdabilidade; Recalcitrância; Propagação; Seleção de clones.
Ano: 2015
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/890

Androgenic response of Brazilian wheat genotypes to different pretreatments of spikes and to a gelling agent
Provedor de dados: 86
Autores: Poersch-Bortolon,Liane Balvedi; Scagliusi,Sandra Maria Mansur; Yamazaki-Lau,Elene; Bodanese-Zanettini,Maria Helena.
Abstract The objective of this work was to analyze the androgenic response of Brazilian wheat genotypes to different pretreatments of the spikes, prior to the culture of isolated microspores, and to the effect of a gelling agent in the induction culture medium. Five genotypes were evaluated for embryo formation, green plant regeneration, and spontaneous chromosome duplication. Wheat spikes were subjected to two pretreatments: cold, at 4ºC for 21 days; and 2-hydroxynicotinic acid, at 32ºC for two days. Culture media were evaluated with or without Ficoll as a gelling agent. Cold produced more embryos and green plants than the chemical pretreatment in four out of five genotypes. Only two genotypes treated with 2-hydroxynicotinic acid were able to produce...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Triticum aestivum; Albinism; Androgenesis; Doubled haploid; Isolated microspore culture; Recalcitrance.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016001101839

Contribution of humic substances from different composts to the synthesis of humin in a tropical soil
Provedor de dados: 90
Autores: Lima,Claudivan Costa; Mendonça,Eduardo de Sá; Roig,Asunción.
The contribution of humic substances of different composts to the synthesis of humin in a tropical soil was evaluated. Increasing doses (0, 13, 26, 52, and 104 Mg ha-1) of five different composts consisting of agroinpowderrial residues were applied to a Red-Yellow Latosol. These composts were chemically characterized and 13C NMR determined and the quantity of the functional alkyl groups of humic acids applied to the soil as compost was estimated. Thirty days after application of the treatments, organic matter samples were collected for fractionation of humic acids (HA), fulvic acids (FA) and humin (HU), from which the ratios HA/FA and (HA + FA)/HU were calculated. The application of the composts based on castor cake resulted in the highest HU levels in the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Humic acids; Fulvic acids; 13C NMR; Alkyl groups; Recalcitrance.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832010000400004

Pinus afforestation in South Brazilian highlands: soil chemical attributes and organic matter composition
Provedor de dados: 63
Autores: Dick,Deborah Pinheiro; Leite,Simone Benvenuti; Dalmolin,Ricardo Simão Diniz; Almeida,Henrique Cesar; Knicker,Heike.
In the last three decades, exotic tree species are being introduced in the natural pastures of the highlands located at the northeastern part of Rio Grande do Sul State (RS), Brazil. This alteration of land use may impart drastic changes in the soil attributes. In this context, this work aimed to evaluate the impact of Pinus taeda afforestation on soil chemical attributes and organic matter (SOM) composition in Leptosols from Campos de Cima da Serra, RS. Soil samples under eight year old (Pi8) and 30 year old (Pi30) Pinus plantations and under native pasture (NP) were studied. Contents of exchangeable cations and of micronutrients and soil pH were determined. The SOM composition was investigated by means of elemental analyses and FTIR spectroscopy. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: FTIR spectroscopy; Humification; Exchangeable cation; Pastures; Recalcitrance.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162011000200007

POLYPHENOLS DISTRIBUTION AND RESERVE SUBSTANCES ANALYSIS IN CACAO SOMATIC EMBRYOGENESIS
Provedor de dados: 37
Autores: GALLEGO RÚA,Adriana María; HENAO RAMÍREZ,Ana María; URREA TRUJILLO,Aura Inés; ATEHORTÚA GARCÉS,Lucía.
In order to understand the causes of lack of regeneration in cacao somatic embryos, two cacao varieties with different responses to regeneration potential were described based on their capacity to store different compounds. It is well known that seed reserves play a central role in the regenerative capability of somatic embryos; thus, we followed histochemical changes and reserve fluctuations of proteins, polysaccharides and polyphenols during somatic embryogenesis (SE) in the two cacao varieties. The study showed that, in somatic embryos of the regenerating variety, polyphenols were localized mainly in the periphery of the embryo (epidermal cells) and proteins were the main storage substance in the embryo expression medium, while the non-regenerating...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antioxidants; Histology; Reserve accumulation; Recalcitrance; Somatic embryogenesis.
Ano: 2016
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2016000200002

Water potential and viability of seeds of Eugenia (Myrtaceae), a tropical tree species, based upon different levels of drying
Provedor de dados: 52
Autores: Delgado,Liliana Ferreira; Barbedo,Claudio José.
The aim of the present work was to study the water potential and viability of Eugenia based upon different levels of drying. The seeds showed high water content at shedding and were sensitive to desiccation; however, the level of this sensitivity (water content) varied among the species. Five target drying levels were defined according to the critical levels of hydration. Results showed that water potential seemed to be more reliable than water content. It was hypothesize that the differences in desiccation tolerance, as well as recalcitrance, among the seeds of different species could be related to the maturity level of these seeds during shedding from the mother plant. Consequently, this could be a result of the evolution on how far the maturation...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Desiccation tolerance; Drying; Seed water relations; Recalcitrance.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132012000400014