Página 1 dos resultados de 3080 itens digitais encontrados em 0.019 segundos

Genetic characterization of fig tree mutants with molecular markers

Rodrigues, M. G. F.; Martins, A. B. G.; Desiderio, J. A.; Bertoni, B. W.; Alves, M. C.
Fonte: FUNPEC-EDITORA; RIBEIRAO PRETO Publicador: FUNPEC-EDITORA; RIBEIRAO PRETO
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.04%
The fig (Ficus carica L.) is a fruit tree of great world importance and, therefore, the genetic improvement becomes an important field of research for better crops, being necessary to gather information on this species, mainly regarding its genetic variability so that appropriate propagation projects and management are made. The improvement programs of fig trees using conventional procedures in order to obtain new cultivars are rare in many countries, such as Brazil, especially due to the little genetic variability and to the difficulties in obtaining plants from gamete fusion once the wasp Blastophaga psenes, responsible for the natural pollinating, is not found in Brazil. In this way, the mutagenic genetic improvement becomes a solution of it. For this reason, in an experiment conducted earlier, fig plants formed by cuttings treated with gamma ray were selected based on their agronomic characteristics of interest. We determined the genetic variability in these fig tree selections, using RAPD and AFLP molecular markers, comparing them to each other and to the Roxo-de-Valinhos, used as the standard. For the reactions of DNA amplification, 140 RAPD primers and 12 primer combinations for AFLP analysis were used. The selections did not differ genetically between themselves and between them and the Roxo-de-Valinhos cultivar. Techniques that can detect polymorphism between treatments...

Mutagênese e tecnologia in vitro no melhoramento genético da pimenta-do-reino (Piper nigrum L.).; Mutagenesis and in vitro technology in the genetic improvement of black pepper (Piper nigrum L.).

Lemos, Oriel Filgueira de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/02/2003 PT
Relevância na Pesquisa
65.98%
O presente trabalho teve por objetivo desenvolver tecnologia in vitro e associá-la à mutagênese, e avaliar plantas V 5 e V6 quanto aos caracteres agronômicos de produção em área de ocorrência da doença fusariose, visando ao melhoramento genético da pimenta-do-reino para obtenção de plantas tolerantes e/ou resistentes à doença fusariose. A aplicação das técnicas in vitro iniciou-se através da obtenção de plantas doadoras de explantes, a partir de estacas em casa-de-vegetação e, de sementes e embriões zigóticos in vitro. O processo de micropropagação foi desenvolvido a partir de gemas de plantas obtidas in vitro através do estabelecimento de condições adequadas de cultivo em meios de cultura apropriados para multiplicação de gemas, enraizamento e obtenção de "plantlets", e de tipo de substrato para aclimatação e formação de mudas. Após a definição deste processo, gemas de plantas de casa-de-vegetação foram submetidas a diferentes tratamentos de assepsia e as sobreviventes micropropagadas. Seleção in vitro foi estabelecida ao cultivar isolados patogênicos do fungo Fusarium solani f. sp. piperis em meio Czapek-Dox e, através da curva de crescimento foi estabelecido o período de 28 dias de cultivo mais adequado para obtenção de filtrado da cultura do fungo. Diferentes concentrações de filtrado e formas de esterilização foram testadas em meio de cultura de multiplicação de gemas e determinou-se a concentração de 55% do filtrado do fungo (v/v) sob a esterilização por duas autoclavagens...

Genetic characterization of fig tree mutants with molecular markers

Rodrigues, M. G. F.; Martins, A. B. G.; Desiderio, J. A.; Bertoni, B. W.; Alves, M. C.
Fonte: Funpec-editora Publicador: Funpec-editora
Tipo: Artigo de Revista Científica Formato: 1990-1996
ENG
Relevância na Pesquisa
46.04%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); The fig (Ficus carica L.) is a fruit tree of great world importance and, therefore, the genetic improvement becomes an important field of research for better crops, being necessary to gather information on this species, mainly regarding its genetic variability so that appropriate propagation projects and management are made. The improvement programs of fig trees using conventional procedures in order to obtain new cultivars are rare in many countries, such as Brazil, especially due to the little genetic variability and to the difficulties in obtaining plants from gamete fusion once the wasp Blastophaga psenes, responsible for the natural pollinating, is not found in Brazil. In this way, the mutagenic genetic improvement becomes a solution of it. For this reason, in an experiment conducted earlier, fig plants formed by cuttings treated with gamma ray were selected based on their agronomic characteristics of interest. We determined the genetic variability in these fig tree selections, using RAPD and AFLP molecular markers, comparing them to each other and to the Roxo-de-Valinhos, used as the standard. For the reactions of DNA amplification, 140 RAPD primers and 12 primer combinations for AFLP analysis were used. The selections did not differ genetically between themselves and between them and the Roxo-de-Valinhos cultivar. Techniques that can detect polymorphism between treatments...

Genetic variation and phylogenetic relationships based on RAPD analysis in section Caulorrhizae, genus Arachis (Leguminosae)

Aparecido Gimenes, Marcos; Romero Lopes, Catalina; Galgaro, Maria Leticia; Montenegro Valls, José Francisco; Kochert, Gary
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 187-195
ENG
Relevância na Pesquisa
46.02%
Wild Arachis germplasm includes potential forage species, such as the rhizomatous Arachis glabrata and the stoloniferous A. pinto and A. repens. Commercial cultivars of A. pintoi have already been released in Australia and in several Latin American countries, and most of these cultivars were derived from a single accession of A. pintoi (GK 12787). Arachis repens is less productive as a forage plant than is A. pintoi. However, it can be crossed with A. pintoi, and thus has good potential as germplasm for the improvement of A. pintoi. Arachis repens is also used as an ornamental plant and ground cover. Many new accessions of these two stoloniferous species are now available, and they harbor significant genetic variability beyond that available in the few older accessions, previously available. Therefore, these new accessions need to be conserved, documented and considered in terms of their potential for crop improvement and direct commercial use. Sixty-four accessions of this new germplasm were analyzed using RAPD analysis. Most of the accessions of A. repens grouped together into a clearly distinct group. In general, the accessions from the distinct valleys of the Jequitinhonha, Sao Francisco and Parana rivers did not group together...

Transferability and use of microsatellite markers for the genetic analysis of the germplasm of some Arachis section species of the genus Arachis

Bravo, Juliana Pereira; Hoshino, Andrea Akemi; Angelici, Carla Maria Lara C.D.; Lopes, Catalina Romero; Gimenes, Marcos Aparecido
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 516-524
ENG
Relevância na Pesquisa
56%
The Arachis section is the most important of the nine sections of the genus Arachis because it includes the cultivated peanut, Arachis hypogaea. The genetic improvement of A. hypogaea using wild relatives is at an early stage of development in spite of their potential as sources of genes, including those for disease and pests resistance, that are not found in the A. hypogaea primary gene pool. Section Arachis species germplasm has been collected and maintained in gene banks and its use and effective conservation depends on our knowledge of the genetic variability contained in this material. Microsatellites are routinely used for the analysis of genetic variability because they are highly polymorphic and codominant. The objective of this study was to evaluate the transferability of microsatellite primers and the assay of genetic variability between and within the germplasm of some species of the Arachis section. Fourteen microsatellite loci developed for three different species of Arachis were analyzed and 11 (78%) were found to be polymorphic. All loci had transferability to all the species analyzed. The polymorphic loci were very informative, with expected heterozygosity per locus ranging from 0.70 to 0.94. In general, the germplasm analyzed showed wide genetic variation. © 2006 Sociedade Brasileira de Genética.

Genetic improvement and population structure of the Nelore breed in Northern Brazil

Malhado,Carlos Henrique Mendes; Carneiro,Paulo Luiz Souza; Malhado,Ana Claudia Mendes; Martins Filho,Raimundo; Bozzi,Riccardo; Ladle,Richard James
Fonte: Embrapa Informação Tecnológica; Pesquisa Agropecuária Brasileira Publicador: Embrapa Informação Tecnológica; Pesquisa Agropecuária Brasileira
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2010 EN
Relevância na Pesquisa
55.98%
The objective of this work was to evaluate the population structure and the genetic and phenotypic progress of Nelore cattle in Northern Brazil. Pedigree information concerning animals born between 1942 and 2006 were analyzed. Population structure was performed using the Endog program. Out of the 140,628 animals studied, 67.7, 14.52 and 3.18% had complete pedigree record of the first, second and third parental generation, respectively. Inbreeding and average relatedness coefficients were low: 0.2 and 0.13%, respectively. However, these parameters may have been underestimated, since information on pedigree was incomplete. The effective number of founders was 370 and the genetic contribution of 10, 50 and 448 most influent ancestors explained 13.2, 28 and 50% of the genetic variability in the population, respectively. The genetic variability for growth traits and population structure demonstrates high probability of increasing productivity through selective breeding. Moreover, management strategies to reduce the currently observed age at first calving and generation intervals are important for Nelore cattle genetic improvement.

Genetic and environmental contributions to increased wheat yield in Minas Gerais, Brazil

Cargnin,Adeliano; Souza,Moacil Alves de; Fronza,Vanoli; Fogaça,Cláudia Martellet
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2009 EN
Relevância na Pesquisa
46.11%
Producers need wheat cultivars adapted to the predominant climate conditions of the end of the rainy period. Having this in mind, EPAMIG (Agriculture and Livestock Research Institute of Minas Gerais) has been developing a wheat genetic improvement program since 1976, and the estimates of the genetic improvement established by the breeding programs could be useful to quantify their efficiency. This study focused on the quantification of the genetic progress achieved by these improvement programs of dryland wheat in the Brazilian-savanna between 1976 and 2005. The efficiency of these programs was evaluated based on grain yield data of VCU (Value for Cultivation and Use) trials conducted at ten locations in the Minas Gerais State, Brazil. The mean estimated genetic progress for mean grain yield between 1976 and 2005 was 37 kg ha-1 year-1. The genetic yield gain in the study period indicates that the improvement programs of dryland wheat in the Brazilian-savanna are effective. Besides the marked contribution of genetic gain, the environmental and technological improvements were also relevant for the yield, accounting for 47.4% of the total progress in the period. The improvement programs of dryland wheat resulted in a genotype renovation rate of 35% over the years.

Marker-Assisted Breeding as Next-Generation Strategy for Genetic Improvement of Productivity and Quality: Can It Be Realized in Cotton?

Boopathi, N. Manikanda; Thiyagu, K.; Urbi, B.; Santhoshkumar, M.; Gopikrishnan, A.; Aravind, S.; Swapnashri, Gat; Ravikesavan, R.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.03%
The dawdling development in genetic improvement of cotton with conventional breeding program is chiefly due to lack of complete knowledge on and precise manipulation of fiber productivity and quality. Naturally available cotton continues to be a resource for the upcoming breeding program, and contemporary technologies to exploit the available natural variation are outlined in this paper for further improvement of fiber. Particularly emphasis is given to application, obstacles, and perspectives of marker-assisted breeding since it appears to be more promising in manipulating novel genes that are available in the cotton germplasm. Deployment of system quantitative genetics in marker-assisted breeding program would be essential to realize its role in cotton. At the same time, role of genetic engineering and in vitro mutagenesis cannot be ruled out in genetic improvement of cotton.

Monitoring Hip and Elbow Dysplasia Achieved Modest Genetic Improvement of 74 Dog Breeds over 40 Years in USA

Hou, Yali; Wang, Yachun; Lu, Xuemei; Zhang, Xu; Zhao, Qian; Todhunter, Rory J.; Zhang, Zhiwu
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 04/10/2013 EN
Relevância na Pesquisa
46.05%
Hip (HD) and Elbow Dysplasia (ED) are two common complex developmental disorders of dogs. In order to decrease their prevalence and severity, the Orthopedic Foundation for Animals (OFA) has a voluntary registry of canine hip and elbow conformation certified by boarded radiologists. However, the voluntarily reports have been severely biased against exposing dogs with problems, especially at beginning period. Fluctuated by additional influential factors such as age, the published raw scores barely showed trends of improvement. In this study, we used multiple-trait mixed model to simultaneously adjust these factors and incorporate pedigree to derive Estimated Breeding Values (EBV). A total of 1,264,422 dogs from 74 breeds were evaluated for EBVs from 760,455 hip scores and 135,409 elbow scores. These EBVs have substantially recovered the reporting bias and the other influences. Clear and steady trends of genetic improvement were observed over the 40 years since 1970. The total genetic improvements were 16.4% and 1.1% of the phenotypic standard deviation for HD and ED, respectively. The incidences of dysplasia were 0.83% and 2.08%, and the heritabilities were estimated as 0.22 and 0.17 for hip and elbow scores, respectively. The genetic correlation between them was 0.12. We conclude that EBV is more effective than reporting raw phenotype. The weak genetic correlation suggested that selection based on hip scores would also slightly improve elbow scores but it is necessary to allocate effort toward improvement of elbow scores alone.

Challenges and opportunities in genetic improvement of local livestock breeds

Biscarini, Filippo; Nicolazzi, Ezequiel L.; Stella, Alessandra; Boettcher, Paul J.; Gandini, Gustavo
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 25/02/2015 EN
Relevância na Pesquisa
46.01%
Sufficient genetic variation in livestock populations is necessary both for adaptation to future changes in climate and consumer demand, and for continual genetic improvement of economically important traits. Unfortunately, the current trend is for reduced genetic variation, both within and across breeds. The latter occurs primarily through the loss of small, local breeds. Inferior production is a key driver for loss of small breeds, as they are replaced by high-output international transboundary breeds. Selection to improve productivity of small local breeds is therefore critical for their long term survival. The objective of this paper is to review the technology options available for the genetic improvement of small local breeds and discuss their feasibility. Most technologies have been developed for the high-input breeds and consequently are more favorably applied in that context. Nevertheless, their application in local breeds is not precluded and can yield significant benefits, especially when multiple technologies are applied in close collaboration with farmers and breeders. Breeding strategies that require cooperation and centralized decision-making, such as optimal contribution selection, may in fact be more easily implemented in small breeds.

Genetic gain in an improvement program of irrigated rice in Minas Gerais.

SOARES, P. C.; MELO, P. G. S.; MELO, L. C.; SOARES, A. A.
Fonte: Crop Breeding and Applied Biotechnology, Viçosa, MG, v. 5, n. 2, p. 142-148, June 2005. Publicador: Crop Breeding and Applied Biotechnology, Viçosa, MG, v. 5, n. 2, p. 142-148, June 2005.
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
56.06%
An evaluation of the genetic improvement programme of irrigated rice of Minas Gerais (Brazil) estimated the genetic gain obtained in the 90s. Grain yield data of the advanced comparative trials of cultivars and lines of continuously flooded rice, conducted from 1990-91 to 2000-01, were used. The estimate of the genetic gain was obtained by the methodology of the adjusted means proposed by Breseghello (1998). The mean annual genetic gain in the 90s was 42.45+or-17.89 kg ha-1 (0.7% per year). The improvement programme proved auspicious for the development of lines that outmatched the controls. The mean of the cultivars released in the 90s did however not outstrip the mean of the elite lines, which were the genotypes with the highest means in this study and will be further evaluated in the ongoing programme.; 2005

Genetic resistance to soil chemical toxicities and deficiencies.

GOURLEY, L.M.; WATSON, C.E.; SCHAFFERT, R.E.; PAYNE, W.A.
Fonte: In: INTERNATIONAL CONFERENCE ON GENETIC IMPROVEMENT OF SORGHUM AND PEARL MILLET, 1996, Lubbock, Texas. Proceedings. Cali: INTSORMIL/ICRISAT, 1997. p.461-480. Publicador: In: INTERNATIONAL CONFERENCE ON GENETIC IMPROVEMENT OF SORGHUM AND PEARL MILLET, 1996, Lubbock, Texas. Proceedings. Cali: INTSORMIL/ICRISAT, 1997. p.461-480.
Tipo: Artigo em anais de congresso (ALICE)
EN
Relevância na Pesquisa
65.94%
Breeding new crop cultivars for adaptation to stress-related phenomena due to soil chemical toxicity and deficiency is a complex process. Data from nutrient culture trials, in which seedling plants are stressed with a deficiency or excess of mineral elements, do not correlate well with those from similar field stress conditions using the same germplasm. Further, evaluating segregating populations in nutrient culture can result in little or no genetic gain due to selection. Field screening efforts are plagued with genotype x environmental interactions caused by a multitude of biotic and abiotic factors. Selecting the proper level of stress for field evaluations and maintaining this level in a dynamically changeable medium like soil can be difficult. Genetic improvement of sorghum under field conditions similar to those encountered by farmers, however, has nearly always been obtained.; 1997

Genetic improvement and population structure of the Nelore breed in Northern Brazil.

MALHADO, C. H. M.; CARNEIRO, P. L. S.; MALHADO, A. C. M.; MARTINS FILHO, R.; BOZZI, R.; LADLE, R. J.
Fonte: Pesquisa Agropecuaria brasileira., Brasília, v.45, n.10, p.1109-1116, out. 2010 Publicador: Pesquisa Agropecuaria brasileira., Brasília, v.45, n.10, p.1109-1116, out. 2010
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
55.98%
Abstract ? The objective of this work was to evaluate the population structure and the genetic and phenotypic progress of Nelore cattle in Northern Brazil. Pedigree information concerning animals born between 1942 and 2006 were analyzed. Population structure was performed using the Endog program. average relatedness coefficients were low: 0.2 and 0.13%, respectively. However,The effective number of founders was 370 and the genetic contribution of 10, 50 and 448 most influent ancestors explained 13.2, 28 and 50% of the genetic variability in the population, respectively. The genetic variability for growth traits and population structure demonstrates high probability of increasing productivity through selective breeding. Moreover, management strategies to reduce the currently observed age at first calving and generation intervals are important for Nelore cattle genetic improvement.; 2010

Genetic improvement and population structure of the Nelore breed in Northern Brazi.

MALHADO, C. H. M.; CARNEIRO, P. L. S.; MALHADO, A. C. M.; MARTINS FILHO, R.; BOZZI, R.; LADLE, R. J.
Fonte: Pesquisa Agropecuaria brasileira., Brasília, v.45, n.10, p.1109-1116, nov. 2010 Publicador: Pesquisa Agropecuaria brasileira., Brasília, v.45, n.10, p.1109-1116, nov. 2010
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
55.98%
Abstract ? The objective of this work was to evaluate the population structure and the genetic and phenotypic progress of Nelore cattle in Northern Brazil. Pedigree information concerning animals born between 1942 and 2006 were analyzed. Population structure was performed using the Endog program. average relatedness coefficients were low: 0.2 and 0.13%, respectively. However,The effective number of founders was 370 and the genetic contribution of 10, 50 and 448 most influent ancestors explained 13.2, 28 and 50% of the genetic variability in the population, respectively. The genetic variability for growth traits and population structure demonstrates high probability of increasing productivity through selective breeding. Moreover, management strategies to reduce the currently observed age at first calving and generation intervals are important for Nelore cattle genetic improvement.; 2010

Estimação de parâmetros genéticos para resistência à infecção por IMNV em camarões Litopenaeus vannamei por meio de análise de sobrevivência; Estimation of genetic parameters for resistance to infection by IMNV in shrimp Litopenaeus vannamei through survival analysis

Kurkjian, Karin
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Produção Animal; Sistemas de Produção Sustentáveis no Semi-árido; Caracterização, conservação e melhoramento genético Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Produção Animal; Sistemas de Produção Sustentáveis no Semi-árido; Caracterização, conservação e melhoramento genético
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
55.94%
The main specie of marine shrimp raised at Brazil and in the world is Litopenaeus vannamei, which had arrived in Brazil in the `80s. However, the entry of infectious myonecrosis virus (IMNV), causing the infectious myonecrosis disease in marine shrimps, brought economic losses to the national shrimp farming, with up to 70% of mortality in the shrimp production. In this way, the objective was to evaluate the survival of shrimps Litopenaeus vannamei infected with IMNV using the non parametric estimator of Kaplan-Meier and a model of frailty for grouped data. It were conducted three tests of viral challenges lasting 20 days each, at different periods of the year, keeping the parameters of pH, temperature, oxygen and ammonia monitored daily. It was evaluated 60 full-sib families of L. vannamei infected by IMNV in each viral challenge. The confirmation of the infection by IMNV was performed using the technique of PCR in real time through Sybr Green dye. Using the Kaplan-Meier estimator it was possible to detect significant differences (p <0.0001) between the survival curves of families and tanks and also in the joint analysis between viral challenges. It were estimated in each challenge, genetic parameters such as genetic value of family...

Estudo gen??tico de duas popula????es de Odontesthes bonariensis atrav??s de marcadores microssat??lites.; Genetic analysis of two populations of Odontesthes bonariensis using microsatellite markers.

TAVARES, Rafael Aldrighi
Fonte: Universidade Federal de Pelotas; Zootecnia; Programa de P??s-Gradua????o em Zootecnia; UFPel; BR Publicador: Universidade Federal de Pelotas; Zootecnia; Programa de P??s-Gradua????o em Zootecnia; UFPel; BR
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
55.98%
Divergency and genetic variability of two populations (Brazil and Argentina) were identified through polymorphism of six microsatellite markers. Eighty Five animals from the two populations were studied, 40 animals collected from Chascomus lake in Buenos Aires, Argentina and 45 from Chasqueiro Dam in Arroio Grande, Rio Grande do Sul, Brazil. The collected material was muscle and caudal fin fragments, stored in 95% ethanol and kept at -20 ??C. Three different protocols for DNA extraction were tested: 1) Phenol Chloroform; 2) Sodium chloride 3) Ammonia acetate (modified Sodium chloride). Six microsatellite loci were analyzed by allelic frequency, observed heterozygosis, expected genetic diversity according to Hardy-Weinberg equilibrium, number of alleles per locus, percentage of polymorphic loci and Wright fixation. The results showed that the microsatellites analyzed presented high polymorphism. The number of alleles varied from 4 to 15. A total of 49 alleles were obtained from all the samples. Fst value between the two populations was 0.1303, that is, the populations presented moderate genetic differentiation (P<0.05). It was concluded that due to the high polymorphism analyzed in the six microsatellite loci, they can be an efficient tool for genetic variation studies of O. bonariensis and the significant genetic differentiation in the populations analyzed can provide basis for further genetic improvement programs.; Foram Identificadas a diverg??ncia e a variabilidade gen??tica de duas popula????es de peixe-rei (Brasil e Argentina)...

Eficiência de transformação genética de citrange 'carrizo' com duas construções gênicas; Genetic transformation efficiency of 'carrizo' citrange with two gene constructions

MIYATA, Luzia Yuriko; MOURÃO FILHO, Francisco de Assis Alves; SCARPARE FILHO, João Alexio; ZAMBON, Flávia; BASSAN, Meire Menezes; MENDES, Beatriz Madalena Januzzi; HARAKAVA, Ricardo
Fonte: Sociedade Brasileira de Fruticultura Publicador: Sociedade Brasileira de Fruticultura
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
55.94%
Transformação genética é considerada uma importante ferramenta auxiliar no melhoramento genético de plantas cítricas. Entretanto, a eficiência de transformação pode variar em função de diversos fatores, incluindo a própria construção gênica utilizada. Este trabalho buscou avaliar a eficiência de transformação genética de plantas de citrange 'Carrizo' [Poncirus trifoliata (L.) Raf. x Citrus sinensis (L.) Osbeck] com duas construções gênicas diferentes contendo o gene uidA (GUS) sob o controle dos promotores Arabidopsis thaliana phloem protein 2 (AtPhP2) e Arabidopsis thaliana sucrose transporter 2 (AtSuT2). Segmentos de epicótilo de plântulas germinadas in vitro foram utilizados como explantes. O gene nptII, que confere resistência ao antibiótico canamicina, foi utilizado nas construções gênicas como agente de seleção para regeneração de plantas transgênicas. O ensaio histoquímico com X-GLUC foi realizado em todas as brotações regeneradas para verificar a expressão do gene uidA. Dos 4.790 segmentos de epicótilo utilizados, registrou-se a regeneração de 366 brotações com reação positiva no ensaio histoquímico, as quais foram enxertadas em porta-enxertos cultivados in vitro. Cinco dessas brotações...

An European network for bean improvement: PHASELIEU

Ron Pedreira, Antonio Miguel de
Fonte: Bean Improvement Cooperative Publicador: Bean Improvement Cooperative
Tipo: Artículo Formato: 268077 bytes; application/pdf
ENG
Relevância na Pesquisa
55.84%
Bean is an important legume for human consumption in Europe, where the sold between exports/imports is minus 360000 t in 1998 (both Phaseolus and Vigna beans are included). So an improved sustainable and more economic common bean production, leading to high quality products would, on the one hand, contribute to the diversification of agricultural systems and the development of more environmental-friendly agricultural practices. On the other hand it would allow for an increased independence from the world market characterised by cost fluctuation and unpredictable supply.; The Concerted Action is carried out with financial support from the Commission of the European Communities. FAIR programme, number FAIR5-PL97-3463, title "Improvement of sustainable Phaseolus production in Europe for human consumption - PHASELIEU".; Peer reviewed

Parâmetros genéticos em teste de procedências e progênies de Toona ciliata M. Roemer var. australis; Genetic parameters in test of provenances and progeny of the Toona ciliata M. Roemer var. australis

Rosado, Lucas Rodrigues
Fonte: Universidade Federal de Lavras; Programa de Pós- Graduação em Engenharia Florestal; UFLA; brasil; Departamento de Ciências Florestais Publicador: Universidade Federal de Lavras; Programa de Pós- Graduação em Engenharia Florestal; UFLA; brasil; Departamento de Ciências Florestais
Tipo: Dissertação
Publicado em 17/12/2015 POR
Relevância na Pesquisa
46.05%
The increase the dimensions of the trees, by genetic improvement, without considering their architectures can make them mechanically unstable in situations of high winds. As consequence may occur falls, breaks and permanent buckling of stems, causing economic losses and environmental damage. In the present study had as objective to estimate genetic parameters and predict wood production gains with improvements in the trees architecture. It was used a test of provenances/progenies/plants of Toona ciliata M. Roemer var. australis, established in Campo Belo, MG, with 74 months old. This test involved 12 provenances of seeds widely distributed in the Australian east coast. Data of diameter to breast height (DBH), total tree height (Ht), volume (Vol), slenderness coefficient (S = Ht.DBH -1 ) and stem form (For), at 31, 54 and 74 months of age, there were obtained in individuals of 63 progenies from all provenances. The genetic parameters and prediction of genotypic values were estimated by REML/BLUP method. There was great genetic variability among and within provenances, showing that the test has an important role for the improvement and conservation of the species ex situ. Whereas the criterion of having a higher frequency of trees with low S or equal to 0.75...

Contribuições genéticas e ambientais para aumento do rendimento do trigo em Minas Gerais, Brasil; Genetic and environmental contributions to increased wheat yield in Minas Gerais, Brazil

Cargnin, Adeliano; Souza, Moacil Alves de; Fronza, Vanoli; Fogaça, Cláudia Martellet
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/06/2009 ENG
Relevância na Pesquisa
46.11%
Devido à necessidade dos produtores por cultivares de trigo adaptados às condições climáticas do final da época das chuvas, desde 1976 a EPAMIG (Empresa de Pesquisa Agropecuária de Minas Gerais) vem desenvolvendo um programa de melhoramento genético. As estimativas dos progressos genéticos alcançados pelos programas de melhoramento são instrumentos hábeis para se quantificar a eficiência dos trabalhos executados. Quantificou-se o progresso genético obtido pelos programas de melhoramento do trigo de sequeiro no cerrado brasileiro no período de 1976 a 2005 utilizando-se resultados de produtividade de grãos obtidos nos ensaios de valor de cultivo e uso. O progresso genético médio anual estimado no período de 1976 a 2005 foi de 37 kg ha-1 ano-1 na produtividade média de grãos. O ganho genético, em produtividade, obtido no período estudado, indica que os programas de melhoramento de trigo de sequeiro no cerrado brasileiro são eficientes. Apesar de o ganho genético ter contribuído expressivamente, as melhorias ambientais e tecnológicas foram importantes para o acréscimo na produtividade, representando 47,4% do progresso total obtido. Os programas de melhoramento de trigo de sequeiro promovem 35% de renovação de genótipos ao longo dos anos.; Producers need wheat cultivars adapted to the predominant climate conditions of the end of the rainy period. Having this in mind...