Consulta: creatorFacets:"Valls,José Francisco Montenegro"
Registros recuperados: 18
Data/hora: 04/06/2024 04:14:18

Successful crosses between fungal-resistant wild species of Arachis (section Arachis) and Arachis hypogaea
Provedor de dados: 74
Autores: Fávero,Alessandra Pereira; Santos,Rodrigo Furtado dos; Simpson,Charles E.; Valls,José Francisco Montenegro; Vello,Natal Antonio.
Peanut (Arachis hypogaea) is the fifth most produced oil crop worldwide. Besides lack of water, fungal diseases are the most limiting factors for the crop. Several species of Arachis are resistant to certain pests and diseases. This study aimed to successfully cross the A-genome with B-K-A genome wild species previously selected for fungal disease resistance, but that are still untested. We also aimed to polyplodize the amphihaploid chromosomes; cross the synthetic amphidiploids and A. hypogaea to introgress disease resistance genes into the cultivated peanut; and analyze pollen viability and morphological descriptors for all progenies and their parents. We selected 12 A-genome accessions as male parents and three B-genome species, one K-genome species,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Peanut; Interspecific hybrids; Polyploidization; Colchicine; Pollen viability.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572015000300353

Characterization of Brazilian accessions of wild Arachis species of section Arachis (Fabaceae) using heterochromatin detection and fluorescence in situ hybridization (FISH)
Provedor de dados: 74
Autores: Custódio,Adriana Regina; Seijo,Guillermo; Valls,José Francisco Montenegro.
The cytogenetic characterization of Arachis species is useful for assessing the genomes present in this genus, for establishing the relationship among their representatives and for understanding the variability in the available germplasm. In this study, we used fluorescence in situ hybridization (FISH) to examine the distribution patterns of heterochromatin and rDNA genes in 12 Brazilian accessions of five species of the taxonomic section Arachis. The heterochromatic pattern varied considerably among the species: complements with centromeric bands in all of the chromosomes (A. hoehnei) and complements completely devoid of heterochromatin (A. gregoryi, A. magna) were observed. The number of 45S rDNA loci ranged from two (A. gregoryi) to eight (A....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Crop wild relatives; Groundnut; RDNA loci; Brazil.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000300011

Chromosome numbers and meiotic behavior of some Paspalum accessions
Provedor de dados: 74
Autores: Adamowski,Eleniza de Victor; Pagliarini,Maria Suely; Bonato,Andréa Beatriz Mendes; Batista,Luiz Alberto Rocha; Valls,José Francisco Montenegro.
Chromosome number and meiotic behavior were evaluated in 36 Brazilian accessions of the grass Paspalum (which had never previously been analyzed) to determinate which accessions might be useful in interspecific hybridizations. The analysis showed that one accession of Paspalum coryphaeum was diploid (2n = 2x = 20) and one accession of Paspalum conspersum hexaploid (2n = 6x = 60), the remaining 34 accessions being tetraploid (2n = 4x = 40). The pairing configuration was typical for the ploidy level i.e. in the diploid, chromosomes paired as 10 bivalents, in tetraploids as bi-, tri- and quadrivalents, and in hexaploid as 30 bivalents. A low frequency of meiotic abnormalities (less than 10%) was observed in the diploid, hexaploid and some tetraploid...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Paspalum; Forage grass; Chromosome numbers; Meiotic behavior.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000500020

Rescue of a non-viable accession and rapd analysis of recovered plants of Arachis retusa
Provedor de dados: 86
Autores: Gagliardi,Rachel Fatima; Pacheco,Georgia Pereira; Oliveira,Carlos Alberto; Carneiro,Leonardo Alves; Valls,José Francisco Montenegro; Vieira,Maria Lucia Carneiro; Mansur,Elisabeth.
In vitro regeneration of Arachis retusa was examined for the purpose of germplasm renewal and conservation. Random amplified polymorphic DNA (RAPD) fingerprinting was used to evaluate the genetic stability of plants derived from embryo axes and apical segments. Ten arbitrary decamer primers were screened and five of them were selected. Ninety genomic regions were evaluated, with an average of 18 loci per clone. All amplified segments were monomorphic. The results indicate that recovered plants are genetically stable at the assessed genomic regions and that both regeneration processes are suitable for in vitro germplasm preservation of Arachis species.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Germplasm conservation; Micropropagation; Molecular characterization; Genetic stability.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2004000200015

Influence of substrates and in vitro preconditioning treatments on ex vitro acclimatization of Arachis retusa
Provedor de dados: 86
Autores: Pacheco,Georgia; Gagliardi,Rachel Fátima; Cogliatti,Mariana Buturini; Manhães,Harlen Barreira; Carneiro,Leonardo Alves; Valls,José Francisco Montenegro; Mansur,Elisabeth.
The objective of this work was to evaluate the influence of substrate and preconditioning treatments on the acclimatization of in vitro plants of Arachis retusa. Plants were transferred to Plantmax or sand, and fertilized with Hoagland's nutrient solution. Plants maintained in sand, with or without fertilizer, showed the highest survival rates. In order to evaluate the influence of in vitro preconditioning treatments, stem segments were cultured on MS medium supplemented with different sucrose concentrations. The highest survival and developmental rates were observed in plants from two accessions cultured on MS supplemented with 1.5% and 3% sucrose. Flowering and fruit production were observed after five months.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Arachis; Groundnut; In vitro conservation; Micropropagation.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2006000100023

Produção de híbridos de amendoim forrageiro por meio de hibridação artificial
Provedor de dados: 86
Autores: Oliveira,Marilda Augusta Peres; Valls,José Francisco Montenegro.
O objetivo deste trabalho foi a obtenção de híbridos de amendoim forrageiro por meio da hibridação artificial. O experimento foi realizado na Embrapa-Centro Nacional de Pesquisa de Recursos Genéticos e Biotecnologia, durante a época de florescimento dos acessos de Arachis pintoi Krap. &amp;amp; W. C. Gregory e de A. repens Handro. Cerca de 700 polinizações produziram 27 segmentos de frutos, com taxas de fecundação que variaram entre 1,1 e 12,9%, considerando-se todas as combinações híbridas. Os híbridos intra-específicos de A. pintoi produziram sementes F2, e os interespecíficos não produziram semente. A técnica de hibridação utilizada nas espécies forrageiras necessitou de ajustes, devido a diferenças observadas em relação ao amendoim cultivado, entre...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Arachis pintoi; Amendoim silvestre; Método de melhoramento; Melhoramento de plantas; Leguminosa.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2002000600019

Duas novas espécies de Paspalum L. (Poaceae: Paniceae) do Brasil
Provedor de dados: 88
Autores: Oliveira,Regina Célia de; Valls,José Francisco Montenegro.
Duas espécies novas de Paspalum L., grupo informal Plicatula, são descritas e ilustradas. Paspalum laurentii L., do Rio Grande do Sul, é reconhecida, principalmente, pelos tricomas longos na margem da ráquis e do pedicelo. Paspalum longipedicellatum L., do Mato Grosso do Sul, possui base flabelada, rizomas curtos com catáfilos velutinos, cobertos por tricomas amarelados, e pedicelos das espiguetas longos, especialmente na porção proximal do racemo.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brasil; Gramineae; Gramíneas; Grupo Plicatula; Mato Grosso do Sul; Rio Grande do Sul.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042009000100009

Morphophysiological characterization of giant missionary grass accessions
Provedor de dados: 96
Autores: Lajús,Cristiano Reschke; Scheffer-Basso,Simone Meredith; Miranda,Mario; Denardin,Rosiane Berenice Nicoloso; Valls,José Francisco Montenegro.
In this study, the phenotypic diversity of five accessions of giant missionary grass (Axonopus jesuiticus × A. scoparius) was evaluated by using morphophysiological traits. Accessions V 14337, V 14403, V 14404, V 14405 and V 14406 are hybrids derived from spontaneous crossing that occurred in Vale do Itajaí, Santa Catarina, Brazil. Plants were cultivated in greenhouse and evaluated at 60, 90, 120, 150, 180, 210 and 240 days of growth. Variation was observed for dry matter production, phenology and morphological traits, showing the possibility of selection. Flowering started at 210 days of growth and only in accessions V 14337 and V 14404. The Mahalanobis distance among accessions ranged from 35.64 (V 14403 and V 14405) to 183.38 (V 14337 and V 14405), and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: A. catharinensis; Dry matter production; Growth analysis; Phenology.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011001100004

Morphological characterization and reproductive aspects in genetic variability studies of forage peanut
Provedor de dados: 63
Autores: Oliveira,Marilda Augusta Peres; Valls,José Francisco Montenegro.
Morphological characterization and the study of reproductive behavior are important procedures to identify desirable traits of progenitors to be included in breeding programs. Morphological descriptors and the reproductive behavior of parental accessions of the legumes Arachis pintoi Krapov &amp;amp; W.C.Gregory and A. repens Handro were analyzed looking for the probable causes of seed production variability. Morphological and reproductive characterization were used for the estimation of the genetic variability of five A. pintoi and two A. repens accessions, with crosses being conducted in a greenhouse. Parents and hybrids have shown high pollen stainability, regular meiosis (2n=20), and presented distinctive reproductive behaviors: A. pintoi accessions GK...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Crossability; Germplasm; Legumes; Wild peanut.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162003000200014

Interspecific hybrids between Paspalum plicatulum and P. oteroi: a key tool for forage breeding
Provedor de dados: 63
Autores: Novo,Patricia Elda; Valls,José Francisco Montenegro; Galdeano,Florencia; Honfi,Ana Isabel; Espinoza,Francisco; Quarin,Camilo Luis.
ABSTRACT Grama-tio-pedro (Paspalum oteroi Swallen) is a rare stoloniferous grass of the Plicatula group of Paspalum, well adapted to continuous grazing in areas subject to seasonal flooding in the Pantanal region, in central western Brazil. The species is a facultative apomictic (asexual reproduction by seed) tetraploid, sporadically cultivated on Pantanal farms, propagated either by cuttings or seed. Due to its potential for extensive cultivation and forage quality, Grama-tio-pedro appears as a candidate for genetic improvement within the Plicatula group through plant breeding. We used a colchicine-induced sexual autotetraploid genotype of P. plicatulum Michx. to obtain interspecific hybrids using the apomictic species, P. oteroi, as pollen donor. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA content; Apomixis; Fertility; Meiosis; Reproductive mode.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162016000400356

Characterization of rust, early and late leaf spot resistance in wild and cultivated peanut germplasm
Provedor de dados: 63
Autores: Fávero,Alessandra Pereira; Moraes,Sérgio Almeida de; Garcia,Antonio Augusto Franco; Valls,José Francisco Montenegro; Vello,Natal Antonio.
Groundnut (Arachis hypogaea) has an AB genome and is one of the most important oil crops in the world. The main constraints of crop management in Brazil are fungal diseases. Several species of the genus Arachis are resistant to pests and diseases. The objective of our experiments was to identify wild species belonging to the taxonomic section Arachis with either A or B (or " non-A" ) genomes that are resistant to early leaf spot (Cercospora arachidicola), late leaf spot (Cercosporidium personatum) and rust (Puccinia arachidis). For the identification of genotypes resistant to fungal diseases, bioassays with detached leaves were done in laboratory conditions, with artificial inoculation, a controlled temperature of 25ºC and a photoperiod of 10 h light/14 h...
Tipo: Info:eu-repo/semantics/report
Palavras-chave: Puccinia arachidis; Cercospora arachidicola; Cercosporidium personatum; Groundnut; Arachis spp.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000100015

Organography of greenhouse and field accessions of wild Arachisspecies (section Arachis)
Provedor de dados: 53
Autores: Veiga,Renato Ferraz de Arruda; Faria,Leonardo de Grazia; Valls,José Francisco Montenegro; Fávero,Alessandra Pereira.
ABSTRACT Peanut or groundnut (Arachis hypogaea L.) is a globally important oilseed crop, with important nutritional qualities, and a rich source of amino acids and protein. Another 80 species have been described in the genus Arachis, 64 of which are found in Brazil, and even though their morphology and agronomic traits remain largely unknown, they have been cultivated for forage and for landscaping and have great potential for breeding with cultivated peanut. Thus, the morphological characterization of wild Arachis species is essential for their conservation and use. In this study, we present a morphological and agronomic characterization of 29 diploid accessions of eleven wild Arachis species and one of the tetraploid A. monticola (section Arachis) with A...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Peanut; Morphological characterization; Descriptors; Principal component analysis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052018000100083

Novos biótipos pentaplóides do grupo Dilatata de Paspalum L. (Gramineae) no Sul do Brasil
Provedor de dados: 65
Autores: Machado,Ana Caroline de Carvalho; Valls,José Francisco Montenegro; Peñaloza,Andréa del Pilar de Souza; Santos,Sileuza dos.
Paspalum dilatatum é uma gramínea nativa da América do Sul subtropical, com bom valor forrageiro e ampla variabilidade intraespecífica. Distintos tipos morfológicos, citológicos e reprodutivos têm sido citados para esta espécie. Paspalum dilatatum "Comum" é o biótipo de maior interesse agronômico. A constatação da importância da espécie como componente da produção de forragem de boa qualidade em campos naturais vem resultando em contínuo interesse pela possibilidade de seu melhor aproveitamento em cultivo. Entre o material do grupo Dilatata submetido à análise, seis acessos de classificação taxonômica não definida apresentaram morfologia distinta dos demais. Acredita-se que sejam resultantes de processos de hibridação natural em combinações antes...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Paspalum dilatatum; Biótipo; Pentaplóide; Hibridação.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782005000100009

Diâmetro dos grãos de pólen e tamanho dos estômatos em acessos diplóides e tetraplóides de Hemarthria altissima (Poiret) Stapf &amp;amp; Hubbard (Gramineae)
Provedor de dados: 65
Autores: Tedesco,Solange Bosio; Battistin,Alice; Valls,José Francisco Montenegro.
Sete acessos da gramínea forrageira Hemarthria altissima, diplóides e tetraplóides africanos e tetraplóides brasileiros, foram analisados com fins de caracterizar, nos diferentes níveis de ploidia, os parâmetros diâmetro dos grãos de pólen e tamanho dos estômatos, com o objetivo de utilizar esses critérios para inferência de níveis de ploidia nessa espécie. As medidas foram feitas com o auxílio de um microscópio com ocular micrométrica. Os resultados demostraram que o diâmetro dos grãos de pólen podem ser utilizados para caracterizar diferentes níveis de ploidia, enquanto que o tamanho dos estômatos não é um critério seguro nessa espécie.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ploidia; Gramínea forrageira; Pólen; Estômatos.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84781999000200014

Cytological and reproductive aspects in the Caespitosa group of Paspalum
Provedor de dados: 65
Autores: Pozzobon,Marisa Toniolo; Paganella,Marcelo Broilo; Santos,Sileuza dos; Valls,José Francisco Montenegro.
Somatic chromosome numbers are reported for thirty four germplasm accessions of Paspalum, Caespitosa group, representing five different species. All five species have shown x=10 as the basic chromosome number. The diploid 2n=20 chromosome number was confirmed for P. chacoense and P. indecorum, as well as sexuality for the latter. This is the first report of the chromosome number and cytological behavior for P. ligulare (2n=20 and 40), P. pleostachyum (2n=20, 30 and 40) and P. redondense (2n=20 and 40). The present results document regular meiosis in diploid accessions, with primarily bivalent pairing at diakinesis and metaphase I. Polyploids of these species had irregular meiosis, with univalent, trivalent, and quadrivalent chromosome associations. Diploid...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Mode of reproduction; Ploidy level.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782013001100014

Citogenética de seis genótipos naturais e introduzidos de Hemarthria altissima (Poiret) Stapf &amp;amp; Hubbard (Gramineae)
Provedor de dados: 65
Autores: Tedesco,Solange Bosio; Battistin,Alice; Valls,José Francisco Montenegro.
Quatro genótipos africanos e dois genótipos brasileiros da gramínea forrageira Hemarthria altissima foram estudados quanto ao número de cromossomos e comportamento meiótico. Foi constatado que o número básico de cromossomos nos genótipos estudados é x=9. Dois genótipos africanos: PI 364878 e UF 553 são diplóides com 2n=2x=18; dois genótipos africanos: PI 347238, GL 460-76 e dois genótipos brasileiros são tetraplóides com 2n=:4x=36 cromossomos. A distribuição dos cromossomos na meiose foi normal em todos os genótipos estudados.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Citogenética; Comportamento meiótico; Gramínea forrageira.
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84781998000200010

Cytogenetic analyses in Paspalum L. reveal new diploid species and accessions
Provedor de dados: 65
Autores: Pozzobon,Marisa Toniolo; Machado,Ana Caroline de Carvalho; Vaio,Magdalena; Valls,José Francisco Montenegro; Peñaloza,Andréa del Pilar de Souza; Santos,Sileuza dos; Côrtes,Ana Luiza; Rua,Gabriel Hugo.
Chromosome numbers were counted in 126 new accessions of 50 Paspalum species from Brazil, Argentina, Paraguay and Bolivia. The chromosome numbers 2n=12, 20, 24, 30, 40, 50, 60, 80 were confirmed. Chromosome numbers for P. arenarium (2n=20), P. barretoi (2n=20), P. aff. ceresia (2n=40), P. corcovadense (2n=20), P. crispulum (2n=20), P. flaccidum (2n=40), P. nummularium (2n=20), P. scalare (2n=20), P. vescum (2n=20) and P. rectum (2n=20) and a diploid cytotype of P. malacophyllum are reported for the first time. The predominance of tetraploid accessions (43.6%) was confirmed, but an unusually high number of diploid species (44%) and accessions (35.7%) was found. These results open new perspectives for breeding programs, phylogenetic studies, and for research...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosome; Diploid; Polyploid; Ploidy level; Hybrid; Genetic resources.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782008000500014

Análise bromatológica comparativa entre acessos diplóides, tetraplóides africanos e tetraplóides brasileiros de Hemarthria altissima (Poiret) Stapf &amp;amp; Hubbard
Provedor de dados: 65
Autores: Tedesco,Solange Bosio; Battistin,Alice; Valls,José Francisco Montenegro.
Foi comparada a qualidade da forragem entre os acessos diplóides e tetraplóides africanos e tetraplóides brasileiros de Hemarthria altissima. O experimento foi conduzido em casa de vegetação na Universidade Federal de Santa Maria. Os resultados obtidos mostraram Digestibilidade in vitro da matéria orgânica satisfatória para os acessos tetraplóides africanos e brasileiros, sendo que os brasileiros tiveram teores de proteína bruta signifi-cativamente maiores que os africanos. O tetraplóide natural do Rio Grande do Sul apresentou maior nível de proteína bruta.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Proteína bruta; Digestibilidade; Diplóides; Tetraplóides.
Ano: 1996
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84781996000300029