870 resultados para Embrapa Uva e Vinho
Resumo:
A região da Serra Gaúcha é uma importante área de produção de uvas e vinhos no sul do Brasil e busca reconhecimento através das Indicações Geográficas (IG) para vinhos finos. A preservação ambiental constitui um requisito importante para definir uma IG. No contexto de um projeto de pesquisa desenvolvido na Embrapa Uva e Vinho, um dos objetivos foi localizar áreas de preservação permanente (APPs) de acordo com o Código Florestal Brasileiro, com o auxílio de técnicas de sensoriamento remoto e geoprocessamento no intuito de identificar os vinhedos em APPs. Para isto foi utilizado o mosaico de fotografias aéreas com resolução espacial de 2 metros. Foi gerado o modelo digital de elevação da rede de drenagem, sendo as áreas de vinhedos obtidas a partir do cadastro de vinhedos pré-existentes do município. A partir do cruzamento das áreas dos vinhedos com as APPs, foram identificados 31% dos vinhedos em área de conflito.
Resumo:
Em videiras 'BRS Clara', cultivar de uvas sem sementes, enxertadas em 'IAC-572' e conduzidas em latada, comparou-se a deposição de calda de pulverização nas folhas utilizando-se corante alimentício, com dois volumes de aplicação: 274 L ha-1 e 500 L ha-1. A eficiência desses dois volumes de calda fungicida foi avaliada, sob cobertura plástica ou não, no controle do míldio da videira, empregando-se os fungicidas recomendados e o programa de pulverização padrão utilizado na região. A severidade da doença, determinada pela porcentagem de área foliar afetada, foi avaliada semanalmente e, com os valores médios da porcentagem de área foliar afetada, determinou-se a curva de progresso da doença para cada tratamento, calculando-se a área abaixo da curva de progresso de míldio (AACPM). Observou-se que quanto maior o volume aplicado, maior o volume depositado nas folhas. Entretanto, a concentração de traçante depositado sobre as folhas foi, em média, 10% menor com a aplicação no volume de 500 L ha-1. Não houve diferença significativa (P? 0,05) entre os níveis de controle de míldio proporcionados pelos dois volumes de aplicação sob cobertura plástica ou não, que reduziram de 87 a 92% a AACPM quando comparados com a testemunha.
Resumo:
2011
Resumo:
Purpose Inadequate soil use and management practices promote commonly negative impacts on the soil constituents and their properties, with consequences to ecosystems. As the soil mineralogy can be permanently altered due to soil use, this approach can be used as a tool to monitor the anthropogenic pressure. The objective of the present study was to assess the mineralogical alterations of a Brazilian regosol used for grape production for 40 years in comparison with a soil under natural vegetation (forest), aiming to discuss anthropogenic pressure on soils. Material and methods Soil samples were collected at depths of 0?0.20 and 0.20?0.40 m from vineyard production and natural vegetation sites. Physical and chemical parameters were analysed by classic approaches. Mineralogical analyses were carried out on <2 mm, silt and clay fractions. Clay minerals were estimated by the relative percentage of peak surface area of the X-ray patterns. Results and discussion Grape production reduced the organic matter content by 28% and the clay content by 23% resulting in a decreasing cation exchange capacity. A similar clay fraction was observed in both soils, containing kaolinite, illite/mica and vermiculite with hydroxy-Al polymers interlayered. Neither gibbsite nor chlorite was found. However, in the soil under native vegetation, the proportion of illite (79 %) was higher than vermiculite (21 %). Whereas, in the soil used for grape production during 40 years, the formation of vermiculite was promoted. Conclusions Grape production alters the proportions of soil constituents of the regosol, reducing clay fraction and organic matter contents, as well as promoting changes in the soil clay minerals with the formation of vermiculite to the detriment of illite, which suggests weathering acceleration and susceptibility to anthropogenic pressure. Recommendations and perspectives Ecosystems in tropical and subtropical climates can be more easily and permanently altered due to anthropogenic pressure, mainly as a consequence of a great magnitude of phenomena such as temperature amplitude and rainfall that occurs in these regions. This is more worrying when soils are located on steep grades with a high anthropogenic pressure, like regosols in Southern Brazil. Thus, this study suggests that changes in soil mineralogy can be used as an important tool to assess anthropogenic pressure in ecosystems and that soil quality maintenance should be a priority in sensible landscapes to maintain the ecosystem quality.
Resumo:
Apples are commercially grown in Brazil in a subtropical environment that favors the development of fungal diseases such as Glomerella leaf spot (GLS) caused mainly by Glomerella cingulata (anamorph Colletotrichum gloeosporioides). The main objective of this work was to evaluate the effect of mixed infections by Apple stem grooving virus (ASGV) and Apple stem pitting virus (ASPV) on the infection and the colonization processes of C. gloeosporiodes in cv. Maxi Gala plants. Leaves of 16-month-old potted plants were spray-inoculated and both the disease incidence and lesion count were monitored over time and leaf severity was assessed in the final evaluation using an image analysis tool. Results showed that initial infection estimated from a monomolecular model fitted to progress of lesion count was higher and the incubation period (time to reach 50% incidence) was on average 10 h shorter in virus-infected plants compared to non-infected plants. It is hypothesized that initial events such as conidial germination and fungal penetration into plant cells were facilitated by the presence of viral infection. Also, final GLS severity was significantly higher in the virus-infected plants. Mixed infections by ASGV/ASPV seemed to make apple leaves more susceptible to the initial infection and colonization by C. gloeosporioides.
Resumo:
The lack of pear-compatible rootstocks in Brazil calls for the application of classical genetic techniques. Therefore, in order to obtain select suitable material, the search for genetic segregation must be continuous, being used as alternative scion cultivars. This study aims to assess fruit set, number of seeds, fruit weight and fruit diameter according to crosses between pear cultivars. The trial was carried out from September 2008 to February 2009 in a commercial orchard in the city of Vacaria/RS, Brazil. For the pollination process, pollen was extracted from flowers at full-white stage in the same orchard. The cultivars used were 'Packham's Triumph' and 'Clapps Favorite'. The crossings were defined as: open pollination; selfpollination of 'Packham's Triumph' and 'Packham's Triumph' × 'Clapps Favorite'. The pollinations were done manually in flowers at full-white stage, which were opened, emasculated and then pollinated. Each pollinated flower was then isolated with a fine nylon bag. Open pollination and cross pollination between 'Packham's Triumph' × 'Clapps Favorite' provided higher fruit set (17 and 18%, respectively). Fruit weight and diameter did not differ between treatments. Open pollination provided fruits with a higher number of seeds.
Resumo:
2012
Resumo:
2012
Resumo:
A gene encoding an elongation factor LeEF-Tsmt that participates in the protein synthesis process in mitochondria shows strong expression in ripening fruit as compared to other organs. It is strongly up-regulated during the first stages of the ripening process in parallel with the climacteric rise in respiration. LeEF-Tsmt expression is stimulated by ethylene, wounding and high temperature but ethylene-insensitive mutants exhibit normal expression. Transgenic fruit have been generated in which LeEF-Tsmt has been constitutively up- and down-regulated. Surprisingly, altering the expression of the gene by genetic transformation with antisense and sense LeEF-Tsmt constructs did not affect the pattern of respiration and ethylene production during ripening and upon wounding. In addition, expression of the alternative oxidase gene which is known to play an important role in respiratory climacteric was not affected. Possible reasons for the absence of effect on respiration of variations of LeEF-Tsmt gene expression are discussed.
Resumo:
2012
Resumo:
2012
Resumo:
A pesquisa em viticultura de precisão deve ser conduzida por meio de zonas de manejo, que podem ser definidas por meio do mapeamento detalhado do solo. No entanto, em termos de pesquisa torna-se necessário avaliar a variabilidade espacial dos atributos do solo, fato que aumenta a demanda por recursos financeiros. Neste trabalho, compara-se a eficiência do mapeamento detalhado dos solos em relação à malha regular de amostragem para definição de zonas de manejo em viticultura de precisão, em estudo de caso no Vale dos Vinhedos, Bento Gonçalves, RS. O estudo sugere que ambos os métodos são complementares, existindo certa dependência com o tipo de solo, colocando em dúvida a possibilidade de eliminação de um dos métodos por motivos de custo.
Resumo:
Pears have been grown in the south region of Brazil, where the climatic conditions are favourable. The aim of this work was to determine the harvest maturity index as well as maximum storage period of 'Packham's Triumph? and 'Rocha' pears to maintain quality attributes. The ?Packham?s Triumph? fruit were harvested from a commercial orchard at 7 days intervals and flesh firmness was used as a maturity index (MI1=76, MI2=67 and MI3=58 N). ?Rocha? pears were harvested twice and they were considered as MI1 and MI3 because of the firmness values. The fruit were stored at 1±1C and 90-95% RH for 15, 30, 45 and 60 days and evaluated at the end of each storage period and after five days at room temperature (24±1C), simulating a helflife period. Flesh firmness, water loss, peduncle dehydration, epidermis colour, soluble solids, titratable acidity were measured. ?Packham?s? pears harvested at MI1 and MI2 showed firmness loss after 30 days of cold storage, whereas fruit harvested at MI3 retained the initial values, resulting in firmer fruit after 60 days (P<0.001). Fruit harvested in MI3 had less firmness loss after 5 days at room temperature following 45 and 60 days of cold storage. ?Rocha? pears harvested in MI1 and MI3 showed firmness reduction during cold storage, which was intensified at room temperature. Maximum values of water loss approached 6%. Fruit peduncles of both cultivars dehydrated after 60 days of cold storage, but their colour remained green, independent of harvest maturity index. ?Packham?s Triumph? and ?Rocha? pears harvested at MI3 showed better quality attributes after 60 days of cold storage plus 5 days of shelf-life than fruit harvested at other maturity stages.
Resumo:
Grapholita molesta (Busck) is one of the main pests of apple trees, and lives on their shoots and fruits. In southern Brazil, the insect is also found on old branches and structures similar to aerial roots, so-called burrknots. This study evaluated the development and population growth potential of G. molesta fed on burrknots, compared with apple fruit cultivar. Fuji and a corn-based artiÞcial diet. The study was carried out in the laboratory under controlled temperature (25 1C), relative humidity (7010%), and photophase (16 h). The biological parameters of the immature and adult stages were determined, and a fertility life table was constructed. Insects fed on burrknots showed a longer duration and a lower survival for the egg-to-adult period (29.3 d and 22.5%) compared with those that fed on apples (25.1 d and 30.0%) and artiÞcial diet (23.9 d and 54.8%). Insects reared on aerial roots had a lower pupal weight (10.0 mg) compared with those reared on either artiÞcial diet (13.7 mg) or apple cultivar. Fuji (12.4 mg). The fecundity and longevity of males and females did not signiÞcantly differ for the three foods. Based on the fertility life table, insects reared on burrknots had the lowest net reproductive rate (Ro), intrinsic rate of population growth (rm) and finite rate of increase, compared with insects reared on artiÞcial diet and apple fruit. Burrknots support the development of the complete cycle of G. molesta, which allows populations of this pest to increase in orchards.
Resumo:
A agricultura familiar apresenta grande relevância para o desenvolvimento social e econômico do Brasil. No entanto, a ampla maioria dos produtores rurais familiares apresenta sérias deficiências gerenciais. Diante disso, baseando-se principalmente em análises de estudos técnico-científicos, buscou-se efetuar reflexões acerca da gestão nos estabelecimentos de agricultura familiar, dando-se ênfase a questões relacionadas com a situação gerencial e com o modelo e os mecanismos que possam ampliar a capacidade de gerenciamento nessas organizações. Dentre os principais resultados e conclusões, destaca-se que, para minimizar os problemas gerenciais dos agricultores familiares, a utilização da visão sistêmica e o envolvimento efetivo desses atores organizacionais são imprescindíveis em todas as etapas de planejamento e execução do modelo de capacitação a ser adotado.