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A cadeia de produção da maçã apresenta importantes impactos socioeconômicos, gerando emprego e renda para diversos trabalhadores 'diretamente envolvidos com a produção, ou indiretamente em toda a cadeia de produção; entretanto, para que a produção tenha sustentabilidade econômica, uma vez que há grande investimento para o estabelecimento dos pomares, e retorno econômico a longo prazo, a produção de frutos de alta qualidade e em grande quantidade, são fundamentais para garantir o retorno dos investimentos; entretanto, dentre os principais riscos associados à cultura é a ocorrência de granizo

Na fruticultura de clima temperado, principalmente para as pomáceas, a regulação do número de frutos representa grande benefício (WERTHEIM, 2000). Após a polinização e a fecundação dos óvulos no gineceu das flores de macieira, até a quinta semana após a antese, ocorre um período de intensa divisão celular, que definirá o número de células disponíveis para expandir e assim definir o tamanho do fruto maduro (LAKSO; GOFFINET, 2013). Nesse contexto, quando se diminui a competição entre os frutos em urna planta, mais assimilados ficam disponíveis aqueles remanescentes, potencializando sua taxa de multiplicação celular, e permitindo maior calibre de fruto na colheita (LAKSO; GOFFINET, 2013; LINK, 2000).

Plantas de macieira produzem excessiva quantidade de flores durante a primavera, as quais nem sempre se convertem em frutos no momento da colheita, resultando em um dispêndio desnecessário de energia produtiva. O mecanismo regulador da carga de frutos atua basicamente em três momentos distintos: logo após a plena floração; quando os frutos estão com 10 a 20 mm de diâmetro; e outro momento antes da colheita. Esses processos visam equilibrar a quantidade de frutos viáveis e a quantidade de fotoassimilados que a planta consegue fornecer para o crescimento (KORALIC, 2010).

Previamente ao lançamento de novas cultivares é importante a realização de estudos para observar o comportamento produtivo de plantas em diferentes condições edafoclimáticas. Este estudo teve como objetivo apresentar características de produção e qualidade físico-química de frutos de genótipos de amoreira-preta cultivados na região dos Campos de Cima da Serra do RS e indicar genótipos com potencial para serem lançados como cultivares ou seguirem no programa de melhoramento genético da cultura. O experimento foi conduzido em 2018, no município de Vacaria/RS, na Embrapa Uva e Vinho - Estação Experimental de Fruticultura de Clima Temperado. Foram avaliados os seguintes genótipos: Cultivares Tupy, Xingu e Xavante e seleções Black 112, Black 139, Black 145, Black 181, Black 198, Black 212, Black 216, Black 287 e Black 288. Foram analisadas as seguintes variáveis: produção - produção por planta, produção por hectare e número de frutos por planta; pós-colheita - massa média, comprimento, diâmetro, relação comprimento/diâmetro dos frutos, sólidos solúveis, pH do suco e acidez total titulável. Observou-se que as seleções Black 145, Black 198 e Black 216, devido à elevada produção de frutos, têm potencial para serem lançadas como novas cultivares, superando a cv. Tupy e igualando a produção da cv. Xingu. Já as seleções Black 287, Black 288 e Black 212 possuem aptidão para consumo in natura, devido às características químicas dos frutos. Palavras Chave: Rubus. Melhoramento genético. Adaptação. Production and fruit quality of blackberry genotypes Prior to the launch of new cultivars, it is important to carry out studies to observe the productive behavior of plants in each soil and climatic condition. The objective of this study was to present production and physical-chemical characteristics of fruits of blackberry genotypes cultivated in the Campos de Cima da Serra do Rio Grande do Sul and to indicate genotypes with potential to be released as cultivars or to follow in the breeding program of culture. The experiment was conducted in 2018, in the municipality of Vacaria/RS, in the Embrapa Uva e Vinho ? Estação Experimental de Fruticultura de Clima Temperado. The following genotypes were evaluated: cultivars Tupy, Xingu and Xavante, and selections Black 112, Black 139, Black 145, Black 181, Black 198, Black 212, Black 216 and Black 288. The following variables were analyzed: production: Production per plant, production per hectare and number of fruits per plant; post-Harvest: average mass, length, diameter, soluble solids, juice pH and titratable total acidity. It was observed that the selections Black 145, Black 198 and Black 216,, due to the high production of fruits, have the potential to be released as new cultivars, surpassing cv. Tupy and equaling the production of cv. Xingu. The Black 287, Black 288 and Black 212 selectionsare suitable for in natura consumption due to the chemical characteristics of the fruits. Key-words: Rubus. Genetical enhancement. Adaptation. Made available in DSpace on 2020-12-09T09:09:49Z (GMT). No. of bitstreams: 1 DeRossi-2020.pdf: 114594 bytes, checksum: 3fcf1698054173b46da7425a5f80c772 (MD5) Previous issue date: 2020

The objective of this study was to investigate the mechanism of action of the treatments: Ammonium thiosulfate (ATS), benzyladenine (BA), GA4+7+BA, foliar fertilizer, lime sulphur (LS), LS+mineral oil, mineral oil, NAA, urea, and vegetal oil in the interaction of these treatments with: 1) pollen grain germination, 2) stigma/style pollen tube (PT) development, and 3) the effectiveness of the treatments in field conditions on decreasing crop load and enhancing fruit quality of "Fuji More" apple trees. In experiment 1 it was evaluated the effect of the treatments in inhibiting the in vitro pollen germination of "Maxi Gala" apples. In Experiment 2 it was evaluated in vivo "Maxi Gala" pollen germination in "Fuji" pistils to assess the effect of the treatments applied 24 h before and after the pollination, in three portions of the styles. In experiment 3 it was evaluated the effect of the treatments sprayed at 90% full bloom in a commercial ?Fuji More? apple orchard on the variables: fruit set, crop load, yield efficiency, mean fruit weight, cluster size, fruit height and diameter, total soluble solids, flesh firmne, mean seed number, skin russet and red color. ATS reduced in vitro pollen germination and caused the greatest damage to the stigmas/styles, while in the field, it was effective to reduce crop load. Treatments containing LS were the most effective to reduce in vitro pollen germination, but the in vivo essay, mode of action seemed to be related to arresting pollen tube growth, and in the field these treatments caused severe russeting. Mineral and vegetal oil do not have direct effect on pollen germination, but arrest pollen tube growth, and in field conditions mineral oil and ATS reduced crop load. All growth regulators (BA, GA4+7 + BA, and NAA decreased greatly crop load and increased fruit weight and quality. Keywords: Mechanism of action Full bloom Alternative Thinning Pollen tube growth Pollen tube stoppage Made available in DSpace on 2019-01-02T23:37:59Z (GMT). No. of bitstreams: 1 EfficacyandmodeofactionofblossomthinnersonFu2019ScientiaHorticu.pdf: 994198 bytes, checksum: cebfdf3b9575c0bbb0a13e4f1d4292d5 (MD5) Previous issue date: 2019-01-02

Apple production in Southern Brazil has been increasing along the past decade, and part of this was due to the introduction of more adapted dwarfing rootstocks and consequently increased tree density in the orchards. Looking for obtaining early beariness, the use of branched nursery trees is one of the most important steps. The objective of this experiment was to determine the effects of plant the growth regulators Benzyladenine (BA), Benzyladenine + Gibberellic acid4+7, Thidiazuron, and Cyclanilide + Ethephon on the induction of lateral branches of ?Maxi Gala? apple trees at nursery, grafted on the rootstocks G.202, G.213, M.9, and Marubakaido with M.9 interstem. The growth regulators Benzyladenine (BA), and Benzyladenine + Gibberellic acid4+7 are the most effective on improving tree?s architecture and on increasing the number of spurs, for all scion-rootstock combinations tested. Plant growth regulators at elevated doses strongly interrupt apical dominance and stimulate an elevated number of lateral branches with narrower crotch angles. Made available in DSpace on 2019-12-27T18:16:40Z (GMT). No. of bitstreams: 1 1s2.0S0304423819302936main.pdf: 2505568 bytes, checksum: b17eafaf51c109e2b43075b70bc29bab (MD5) Previous issue date: 2019

Tumours shows aberrant DNA methylation patterns, being hypermethylated or hypomethylated compared with normal tissues. In human acute myeloid leukaemia (hAML) mutations in DNA methyltransferase (DNMT3A) are associated to a more aggressive tumour behaviour. As AML is lethal in dogs, we defined global DNA methylation content, and screened the C-terminal domain of DNMT3 family of genes for sequence variants in 39 canine acute myeloid leukaemia (cAML) cases. A heterogeneous pattern of DNA methylation was found among cAML samples, with subsets of cases being hypermethylated or hypomethylated compared with healthy controls; four recurrent single nucleotide variations (SNVs) were found in DNMT3L gene. Although SNVs were not directly correlated to whole genome DNA methylation levels, all hypomethylated cAML cases were homozygous for the deleterious mutation at p. Arg222Trp. This study contributes to understand genetic modifications of cAML, leading up to studies that will elucidate the role of methylome alterations in the pathogenesis of AML in dogs.

A planta de macieira produz quantidades excessivas de flores, que nem sempre se transformarão em frutos. Para se produzir frutos de qualidade comercial, deve-se realizar raleio químico de flores ou frutos para melhor distribuição de fotoassimilados. Entretanto, para reduzir custos de produção, o raleio químico é uma técnica amplamente utilizada. Para maior segurança no uso dessa técnica, faz-se necessário compreender os efeitos de parâmetros climáticos sobre o padrão de abscisão de frutos na cultura. Avaliou-se por dois anos consecutivos o padrão de queda de frutos de macieira para comparar-se com dados de radiação, e temperaturas máximas e mínimas. Nas condições edafoclimáticas avaliadas, houve interferência do clima sobre a taxa de abscisão de frutos. Sempre que há baixa incidência de radiação solar e elevadas temperaturas noturnas, há uma tendência de ocorrer picos de abscisão de frutos nos dias subsequentes. Made available in DSpace on 2019-01-02T23:38:11Z (GMT). No. of bitstreams: 1 PARAMETROSCLIMATICOSNOPADRAODESENE...MAXIGALANOMUNICIPIODEVACARIARS.pdf: 451079 bytes, checksum: 756d8f8204d22b8182a4a67d64290bb9 (MD5) Previous issue date: 2019-01-02

The aim of the experiment is to evaluate the physical and chemical effects caused on the properties of red latosol containing high levels of organic matter in the aftermath of 40 months after surface liming and the effects on yield components of no-till maize. The experiment was conducted in an area of 1000 m 2 split into 40 plots of 25 m 2 , and the experimental design adopted was randomized complete blocks with five treatments and four replications. The treatments consisted of five rates of lime: 0, 2.5, 5, 12.5 and 30 ton.ha-1 (1 SMP pH 5.5). After 40 months of experiment installation, soil samples were taken in a total of four sub samples per plot, that were properly homogenized at different depths (0 to 5, 5 to 10 and 10 to 20 cm) and evaluated on chemical parameters (pH, H+Al, Ca, Mg, Al saturation and bases); on physical parameters (resistance to penetration and soil water infiltration) and on maize crop parameters (yield, height of insertion of first cob and plant?s height). It was observed that equal and above 1 SMP to pH 5.5 ameliorated soil pH in the layers up to 20 cm after 40 months of application, interfering in the levels of Al+H, Ca, Mg, saturation of bases and saturation of aluminum. However, significant effects on soil pH were observed in a depth up to 10 cm. The application of different surface liming rates did not interfere on penetration resistance or soil water infiltration capacity. The effects on soil chemical properties with the rate of 1 SMP to pH 5.5 resulted in higher maize grain yield. Key words: Chemical correction, soil physics, maize, acidity. Made available in DSpace on 2017-10-21T09:26:32Z (GMT). No. of bitstreams: 1 GEBLERaFRICANjOURNALOFaGRICULTURALrESEARCHv12n39pp295429602017.pdf: 703487 bytes, checksum: 43b1d8b0aa1349e9f182e97bacd0c4a3 (MD5) Previous issue date: 2017-10-20