986 resultados para Plant breeding education
Resumo:
O melhoramento genético animal é, normalmente, pesquisado e desenvolvido nas universidades e instituições públicas de pesquisa do Brasil. No entanto, os rebanhos de exploração zootécnica, verdadeiros objetivos desses estudos, pertencem à iniciativa privada. O melhoramento genético animal e as parcerias público-privadas constituem-se em um caso especial de grande sucesso, que é analisado no presente texto, com ênfase especial ao Grupo de Melhoramento Animal e Biotecnologia da Faculdade de Zootecnia e Engenharia de Alimentos da Universidade de São Paulo, instituição de origem dos autores. O sucesso desse grupo, medido em atividades de pesquisa e suas conseqüentes publicações, de ensino e formação de recursos humanos e de extensão de serviços à comunidade, é apresentado como incentivo aos pesquisadores das mais diversas áreas ligadas à produção animal.
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Ferruginous "campos rupestres" are a particular type of vegetation growing on iron-rich primary soils. We investigated the influence of soil properties on plant species abundance at two sites of ferruginous "campos rupestres" and one site of quartzitic "campo rupestre", all of them in "Quadrilátero Ferrífero", in Minas Gerais State, southeastern Brazil. In each site, 30 quadrats were sampled to assess plant species composition and abundance, and soil samples were taken to perform chemical and physical analyses. The analyzed soils are strongly acidic and presented low fertility and high levels of metallic cations; a principal component analysis of soil data showed a clear segregation among sites due mainly to fertility and heavy metals content, especially Cu, Zn, and Pb. The canonical correspondence analysis indicated a strong correlation between plant species abundance and soil properties, also segregating the sites.
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We examined the distribution, abundance and density of the Kelp Gull, Larus dominicanus (Lichtenstein, 1823), at Keller Peninsula on two occasions during the breeding season of 2007-2008 (once for incubation and once for chick stages) and compared our results with previously published data. We present information on the number of eggs, incubation success, and initial development of L. dominicanus chicks in the studied sites. The abundance and density of the species has remained statistically similar in Keller Peninsula over the last 30 years (since 1978-1979). Although the abundance and density were almost unchanged, we recorded alterations in the occupation of the breeding areas by L. dominicanus, mainly the abandonment of breeding sites in the eastern portion of Keller Peninsula. The results of the present study compared with similar previous investigations on the abundance of L. dominicanus indicate that the populations have been in equilibrium over the years.
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This paper addresses the capacitated lot sizing problem (CLSP) with a single stage composed of multiple plants, items and periods with setup carry-over among the periods. The CLSP is well studied and many heuristics have been proposed to solve it. Nevertheless, few researches explored the multi-plant capacitated lot sizing problem (MPCLSP), which means that few solution methods were proposed to solve it. Furthermore, to our knowledge, no study of the MPCLSP with setup carry-over was found in the literature. This paper presents a mathematical model and a GRASP (Greedy Randomized Adaptive Search Procedure) with path relinking to the MPCLSP with setup carry-over. This solution method is an extension and adaptation of a previously adopted methodology without the setup carry-over. Computational tests showed that the improvement of the setup carry-over is significant in terms of the solution value with a low increase in computational time.
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Results obtained in a pilot-scale unit designed for COD removal and p-TBC (p-tert-butylcatechol) recovery from a butadiene washing stream (pH 14, 200,000 mg COD L-1, highly toxic) at a petrochemical industry are presented. By adding H3PO4, phase separation is achieved and p-TBC is successfully recovered (88 g L-1 of washing stream). Information (time for phase separation and organic phase characterization) was gathered for designing a future industrial unit. The estimated heat generation rate was 990 kJ min-1 and 15 min were enough to promote phase separation for a liquid column of approximately 1.15 m.
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The objective of this study was to extract and concentrate calcium oxalate (CaOx) crystals from plant leaves that form the above mentioned crystals. The chemical and physical studies of CaOx from plant to be performed depend on an adequate amount of the crystals. The plant used in this study was croton (Codiaeum variegatum). The leaves were ground in a heavy duty blender and sieved through a 0.20 mm sieve. The suspension obtained was suspended in distilled water. The crystals were concentrated at the bottom of a test tube. The supernatant must be washed until it is free of plant pigments and other organic substances. Biogenic CaOx crystals have well-defined and sharp peaks, indicating very high crystallinity. Moreover, the CaOx crystals were not damaged during the extraction procedure, as can be seen on the scanning electron microscope images. The porposed method can be considered efficient to extract and concentrate biogenic calcium oxalate.
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Yellow fever (YF) is an acute viral infectious disease transmitted by mosquitoes which occurs in two distinct epidemiological cycles: sylvatic and urban. In the sylvatic cycle, the virus is maintained by monkey's infection and transovarian transmission in vectors. Surveillance of non-human primates is required for the detection of viral circulation during epizootics, and for the identification of unaffected or transition areas. An ELISA (enzyme-linked immunosorbent assay) was standardized for estimation of the prevalence of IgG antibodies against yellow fever virus in monkey sera (Alouatta caraya) from the reservoir area of Porto Primavera Hydroelectric Plant, in the state of São Paulo, Brazil. A total of 570 monkey sera samples were tested and none was reactive to antibodies against yellow fever virus. The results corroborate the epidemiology of yellow fever in the area. Even though it is considered a transition area, there were no reports to date of epizootics or yellow fever outbreaks in humans. Also, entomological investigations did not detect the presence of vectors of this arbovirus infection. ELISA proved to be fast, sensitive, an adequate assay, and an instrument for active search in the epidemiological surveillance of yellow fever allowing the implementation of prevention actions, even before the occurrence of epizootics.
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A febre amarela (FA) é doença infecciosa aguda de origem viral transmitida por mosquitos. No ciclo silvestre, o vírus é mantido por meio da infecção de macacos e da transmissão transovariana nos vetores. A vigilância sobre populações de primatas não humanos torna-se necessária para detectar a circulação viral, quando ainda está restrito a epizootias, e para determinar sua presença em regiões indenes ou de transição para a doença. Padronizou-se a técnica ELISA (Enzyme Linked Immunosorbent Assay) para determinar a prevalência de anticorpos da classe IgG contra o vírus da FA em soros de bugios (Alouatta caraya) da região do reservatório da Usina Hidrelétrica de Porto Primavera, SP. Foram testados soros de 570 macacos sendo que nenhuma amostra mostrou-se reativa para a presença de anticorpos contra o vírus da FA. Os resultados são coerentes com a epidemiologia da FA na região. Mesmo sendo área de transição, não se conhece, até o momento, ocorrência de epizootia ou surto de FA em humanos e investigações entomológicas não apontaram a presença de vetores para esta arbovirose. A técnica mostrou-se sensível, rápida e útil à vigilância epidemiológica como instrumento de busca ativa permitindo desencadear ações preventivas, como vacinação, antes mesmo do surgimento de epizootias
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Equatorial podzols are soils characterized by thick sandy horizons overlying more clayey horizons. Organic matter produced in the topsoil is transferred in depth through the sandy horizons and accumulate at the transition, at a depth varying from 1 to more than 3 m, forming deep horizons rich in organic matter (Bh horizons). Although they cover great surfaces in the equatorial zone, these soils are still poorly known. Studying podzols from Amazonia, we found out that the deep Bh horizons in poorly drained podzol areas have a thickness higher than 1m and store unexpected amounts of carbon. The average for the studied area was 66.7 +/- 5.8 kgCm(-2) for the deep Bh and 86.8 +/- 7.1 kgCm(-2) for the whole profile. Extrapolating to the podzol areas of the whole Amazonian basin has been possible thanks to digital maps, giving an order of magnitude around 13.6 +/- 1.1 PgC, at least 12.3 PgC higher than previous estimates. This assessment should be refined by additional investigations, not only in Amazonia but in all equatorial areas where podzols have been identified. Because of the lack of knowledge on the quality and behaviour of the podzol organic matter, the question of the feedback between the climate and the equatorial podzol carbon cycle is open.
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Nowadays in Brazil, some social organizations, governments and mass media are discussing the need to establish an oversight committee to guarantee the quality of television programmes, as well as the need to set a system to determine what kind of pro, gram is appropriate for every television time slot. Across Brazil, a representative body of children and young people have come to the conclusion that the right to receive quality television programmes is not enough. The children of the new generations think they have the right to access new technologies and the production of their own messages, in accordance with their own creativity, interests and lifestyle projects within society.
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Social organizations, local governments and the media in Brazil are confronting them, selves over the need for an oversight board to guarantee quality television programming, and establishing a system to determine which television programs are appropriate for which television time slots. Across Brazil, a representative body of children and young adults have determined that the right to receive quality programming is not currently being met. Children of the new generation see themselves as having a right to access new technologies which enable them to produce their own messages according to their own creativity, interests, and social participation. This new generation wants to go beyond education in order to watch and conquer their ""right to screens"".
Resumo:
Background: The tomato (Solanum lycopersicum L.) plant is both an economically important food crop and an ideal dicot model to investigate various physiological phenomena not possible in Arabidopsis thaliana. Due to the great diversity of tomato cultivars used by the research community, it is often difficult to reliably compare phenotypes. The lack of tomato developmental mutants in a single genetic background prevents the stacking of mutations to facilitate analysis of double and multiple mutants, often required for elucidating developmental pathways. Results: We took advantage of the small size and rapid life cycle of the tomato cultivar Micro-Tom (MT) to create near-isogenic lines (NILs) by introgressing a suite of hormonal and photomorphogenetic mutations (altered sensitivity or endogenous levels of auxin, ethylene, abscisic acid, gibberellin, brassinosteroid, and light response) into this genetic background. To demonstrate the usefulness of this collection, we compared developmental traits between the produced NILs. All expected mutant phenotypes were expressed in the NILs. We also created NILs harboring the wild type alleles for dwarf, self-pruning and uniform fruit, which are mutations characteristic of MT. This amplified both the applications of the mutant collection presented here and of MT as a genetic model system. Conclusions: The community resource presented here is a useful toolkit for plant research, particularly for future studies in plant development, which will require the simultaneous observation of the effect of various hormones, signaling pathways and crosstalk.
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The pathogenic fungus Fusarium graminearum is an ongoing threat to agriculture, causing losses in grain yield and quality in diverse crops. Substantial progress has been made in the identification of genes involved in the suppression of phytopathogens by antagonistic microorganisms; however, limited information regarding responses of plant pathogens to these biocontrol agents is available. Gene expression analysis was used to identify differentially expressed transcripts of the fungal plant pathogen F. graminearum under antagonistic effect of the bacterium Pantoea agglomerans. A macroarray was constructed, using 1014 transcripts from an F. graminearum cDNA library. Probes consisted of the cDNA of F. graminearum grown in the presence and in the absence of P. agglomerans. Twenty-nine genes were either up (19) or down (10) regulated during interaction with the antagonist bacterium. Genes encoding proteins associated with fungal defense and/or virulence or with nutritional and oxidative stress responses were induced. The repressed genes coded for a zinc finger protein associated with cell division, proteins containing cellular signaling domains, respiratory chain proteins, and chaperone-type proteins. These data give molecular and biochemical evidence of response of F. graminearum to an antagonist and could help develop effective biocontrol procedures for pathogenic plant fungi.
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QTL mapping provides usefull information for breeding programs since it allows the estimation of genomic locations and genetic effects of chromossomal regions related to the expression of quantitative traits. The objective of this study was to map QTL related to several agronomic important traits associated with grain yield: ear weight (EW), prolificacy (PROL), ear number (NE), ear length (EL) and diameter (ED), number of rows on the ear (NRE) and number of kernels per row on the ear (NKPR). Four hundred F-2:3 tropical maize progenies were evaluated in five environments in Piracicaba, Sao Paulo, Brazil. The genetic map was previously estimated and had 117 microssatelite loci with average distance of 14 cM. Data was analysed using Composite Interval Mapping for each trait. Thirty six QTL were mapped and related to the expression of EW (2), PROL (3), NE (2), EL (5), ED (5), NRE (10), NKPR (5). Few QTL were mapped since there was high GxE interaction. Traits EW, PROL and EN showed high genetic correlation with grain yield and several QTL mapped to similar genomic regions, which could cause the observed correlation. However, further analysis using apropriate statistical models are required to separate linked versus pleiotropic QTL. Five QTL (named Ew1, Ne1, Ed3, Nre3 and Nre10) had high genetic effects, explaining from 10.8% (Nre3) to 16.9% (Nre10) of the phenotypic variance, and could be considered in further studies.