Root system morphology of ipê-roxo tree grown in soil subjected to phosphorus application in subtropical climate region

Phosphorus (P) availability in subtropical soils does not often meet the nutritional demand of native tree species such as the ipê-roxo tree (Handroanthus heptaphyllus); therefore, it is necessary to supply P at planting. However, the impact of P on root system growth remains unknown. The aim of the current study was to investigate the effect of P application on root morphology of H. heptaphyllus plants over a 36-month period in a subtropical climate region. During the experiment, the plants subjected to fertilization with 40 kg P ha−1 were compared to untreated control. Plant roots were scanned through minirhizotron system 18 and 36 months after transplant (MAT), and generated images were used to determine total root length, mean root diameter and total root volume. Plant height and leaf P concentrations were also evaluated. Phosphorus application enhanced root and whole plant growth with a more evident effect at 36 MAT, when soil P availability decreased. The results give important information on the cultivation of H. heptaphyllus plants in soils presenting low P availability

Kinetic parameters related to nitrogen uptake efficiency of pear trees (Pyrus communis).

Genetic improvement programs for pear trees in Brazil are characterized by rootstock (hypobiotic) selection mainly considering physiological attributes such as vigor, breakage of dormancy, propagation easiness, and sanitary characteristics, such as resistance to pests and diseases. However, kinetic parameters that determine nutrient uptake efficiency are not usually considered as, for example, nitrogen (N) in forms of NO3 − and NH4 +. The objective of this study was to evaluate the kinetic parameters related to N uptake in pear selection '54′ and '971′ as additional criteria for rootstock selection. The plants were acclimatized in a half-strength Hoagland solution and tested to assess the depletion of the internal reserves at 15 and 30 days, in CaSO4 solution to evaluate the depletion period during 65 h. The selection '971′ showed more significant NO3 − and NH4 + uptake efficiency, because presented higher Vmax values and Influx. The internal reserve depletion (IRD) period for the evaluated selections was 30 days in CaSO4 solution. The evaluation period of the depletion period to reach the Cmin for selections '971′ and '54′ was 64 and 65 h for NO3 − respectively, and 65 h for NH4 +. The selection '971′ had a higher affinity with the NO3 − ion when correlated with the physiological parameters of minimum fluorescence (Fo) and electron transport rate (ETRm)

Fertirrigação e lixiviação de nitrogênio em solo arenoso de vinhedo.

XV Congresso Latino-Americano de Viticultura e Enologia E XIII Congresso Brasileiro de Viticultura e Enologia. Bento Gonçalves-RS, 3 a 7 de Novembro de 2015

Kinetic parameters govern of the uptake of nitrogen forms in "Paulsen" and "Magnolia" grapevine rootstocks.

Grapevine rootstocks are selected according to graft compatibility, pathogen tolerance and water stress. However, morphological and kinetic parameters of nutrient absorption, such as nitrate (NO3 −) and ammonium (NH4 +), usually are not considered. The study aimed to select, based on morphological and kinetic absorption parameters, grapevine rootstocks with greater efficiency of N-forms absorption. The study was performed with two grapevine rootstocks (?Paulsen 1103? and ?Magnolia?), grown in Hoagland nutrient solution in a greenhouse. After 21 d, they were placed in 0.05 mol L-1 CaSO4 solution for 20 d to exhaust nutrient internal reserves. The rootstock with highest NO3 − and NH4 + uptake efficiency was ?Paulsen 1103?, since it presented lower Cmin and Km values in the two N forms, allowing N extraction by roots, even in low concentrations in solution, due to the higher transporter affinity for NO3 − and NH4 + in roots from rootstock. ?Paulsen 1103? rootstock also presented better photosynthetic performance and root development, collaborating for greater growth and mass production than 'Magnolia' rootstock. On the other hand, ?Magnolia? rootstock showed higher NO3 − and NH4 + Cmin and Km values than ?Paulsen? rootstock, which shows lower transporters affinity for these ions. Results demonstrate the importance of the use of NO3 − and NH4 + uptake kinetic parameters in grapevine rootstock selection programs, since these may serve as indicator of plant's ability to absorb NO3 − and NH4 + in low concentrations

Calagem, adubação e estado nutricional em videiras.

A área cultivada com videira no Brasil e, especialmente, no Sul do país, como no Rio Grande do Sul (RS) e Santa Catarina (Se), tem aumentado nos últimos anos. Porém, na maioria dos casos os solos são ácidos e possuem baixa fertilidade natural. Por isso, torna- se necessário, quando diagnosticada a necessidade, a aplicação de corretivos da acidez do solo e adubações. Mas, estas práticas devem ser realizadas seguindo as recomendações técnicas oficiais recomendadas para a cultura da videira, pois normalmente afetam a produção e qualidade da uva, bem como do mosto e de seus subprodutos, como o vinho, sucos e espumantes. Considerando esta problemática, no presente capítulo serão apresentadas informações técnicas sobre calagem, adubações e composição nutricional de videiras. Além disso, serão apresentados resultados de pesquisa mais recentes sobre a dinâmica de nutrientes em solos de vinhedos, bem como o impacto de nutrientes sobre as características físicas e químicas do vinho, temática ainda pouco estudada no Brasil. Com todas as informações esperamos contribuir para um sistema de produção vitivinícola mais produtivo, com uvas e seus subprodutos com melhor qualidade requisitada pelo consumidor, mas com baixo potencial de risco ambienta I

Procedimentos para avaliação de parâmetros cinéticos na absorção de nutrientes em videiras.

A maioria dos solos são carentes de nutrientes e exigem adubações. E as espécies e variedades cultivadas também podem apresentar baixa eficiência na absorção dos nutrientes, prejudicando o crescimento, produtividade e qualidade dos frutos. Como consequência, parte dos nutrientes aplicados via adubações pode ser desperdiçado, contribuindo com perdas e contaminações. Por isso, metodologias que contribuem para a seleção de genótipos mais eficientes na absorção de nutrientes, especialmente das formas de nutrientes mais móveis nos solos, são de extrema importância. Esta publicação apresenta uma metodologia inovadora para estimar os parâmetros cinéticos da absorção de nutrientes em videiras ainda no estágio de mudas, envolvendo a velocidade máxima de absorção, a constante de Michaelis-Menten, a concentração mínima e o influxo. A análise conjunta desses parâmetros cinéticos permite definir quais as variedades ou seleções avançadas possuem potencial para se adaptar aos solos com baixa fertilidade natural, ou mesmo, que podem receber menores doses de nutrientes, racionalizando o manejo da adubação e diminuindo os custos de produção

From fuzzy to annotated semantic web languages

The aim of this chapter is to present a detailed, selfcontained and comprehensive account of the state of the art in representing and reasoning with fuzzy knowledge in Semantic Web Languages such as triple languages RDF/RDFS, conceptual languages of the OWL 2 family and rule languages. We further show how one may generalise them to so-called annotation domains, that cover also e.g. temporal and provenance extensions

Distribution and genetic diversity of the human polyomaviruses JC and BK in surface water and sewage treatment plant during 2009 in Porto Alegre, Southern Brazil

Abstract The human polyomaviruses JC and BK (JCPyV and BKPyV) are ubiquitous, species-specific viruses that belong to the family Polyomaviridae. These viruses are known to be excreted in human urine, and they are potential indicators of human wastewater contamination. In order to assess the distribution of both JCPyV and BKPyV in urban water samples collected from a sewage treatment plant (STP) and from a canalized water stream of Porto Alegre, Brazil, two nested-PCR assays were optimized and applied to the samples collected. The amplicons obtained were submitted to sequencing, and the sequences were analyzed with sequences of human polyomaviruses previously deposited in GenBank. Twelve out of 30 water samples (40%) were JCPyV positive, whereas six samples (20%) were BKPyV positive. The sequencing results confirmed the presence of JCPyV subtypes 1 and 3, whereas only BKPyV Ia and Ib were found. This study shows for the first time the presence of human polyomaviruses in surface water and in samples collected in a sewage treatment plant in southern Brazil

Distribution and genetic diversity of the human polyomaviruses JC and BK in surface water and sewage treatment plant during 2009 in Porto Alegre, Southern Brazil

Abstract The human polyomaviruses JC and BK (JCPyV and BKPyV) are ubiquitous, species-specific viruses that belong to the family Polyomaviridae. These viruses are known to be excreted in human urine, and they are potential indicators of human wastewater contamination. In order to assess the distribution of both JCPyV and BKPyV in urban water samples collected from a sewage treatment plant (STP) and from a canalized water stream of Porto Alegre, Brazil, two nested-PCR assays were optimized and applied to the samples collected. The amplicons obtained were submitted to sequencing, and the sequences were analyzed with sequences of human polyomaviruses previously deposited in GenBank. Twelve out of 30 water samples (40%) were JCPyV positive, whereas six samples (20%) were BKPyV positive. The sequencing results confirmed the presence of JCPyV subtypes 1 and 3, whereas only BKPyV Ia and Ib were found. This study shows for the first time the presence of human polyomaviruses in surface water and in samples collected in a sewage treatment plant in southern Brazil