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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Resultados da Pesquisa
Item Incubation period of Hemileia vastatrix in coffee plants in Brazil simulated under climate change(Grupo Paulista de Fitopatologia, 2011) Ghini, Raquel; Hamada, Emília; Pedro Júnior, Mário José; Gonçalves, Renata Ribeiro do ValleRisk analysis of climate change on plant diseases has great importance for agriculture since it allows the evaluation of management strategies to minimize future damages. This work aimed to simulate futures cenarios of coffee rust (Hemileia vastatrix) epidemics by elaborating geographic distribution maps using a model that estimates the pathogen incubation period and the output from three General Circulation Models (CSIRO-Mk3.0, INM-CM3.0, and MIROC3.2.medres). The climatological normal from 1961-1990 was compared with that of the decades 2020s, 2050s and 2080s using scenarios A2 and B1 from the IPCC. Maps were prepared with a spatial resolution of 0.5 × 0.5 degrees of lat itude and longitude for ten producing states in Brazil. The climate variables used were maximum and minimum monthly temperatures. The maps obtained in scenario A2 showed a tendency towards a reduction in the incubation period when future scenarios are compared with the climatological normal from 1961-1990. A reduction in the period was also observed in scenario B1, although smaller than that in scenario A2.Item Shading effect on coffee tree in formation stage(Editora UFLA, 2019-04) Franco Junior, Kleso Silva; Florentino, Ligiane AparecidaAccording to the Intergovernmental Panel on Climate Change, global warming is expected with temperature rise and changes in the rainfall in tropical regions, including soil warming, which may lead losses to perennial plants. This phenomenon causes researchers to search through science alternatives in order to minimize these impacts. The objective in this research was to evaluate the cultivation of different plants in a intercropping for the coffee tree shading and its influence on the seedlings establishment, development, coffee growth and the maintenance of lower soil temperatures. The experiment was carried out at the Santa Felicidade Site, Campestre - municipality - South of MG , located at 21 ° 43’ 12 “South and 46 ° 14’ 46” West at an altitude of 1.106 meters. The cultivar used was the Catuai IAC 144, was intercropped with the following species: maize (Zea mays L.), guandu (Cajanus cajan L.), crotalaria (Crotalaria spectabilis L.), mucuna (Stizolobium aterrimun) and control without any intercrop, totaling five treatments. The plants sowing for shading was performed using a manual planter and the planting was done in 4 plots per treatment, totaling 20 experimental units in a randomized block design with 14 coffee plants per plot. The 10 central plants were analyzed. At the end of the experiment, the following characteristics were evaluated: seedlings establishment, growth in height, average length of plagiotropic branches, number of internodes in plagiotropic branches, coffee canopy and soil temperature. The data were statistically interpreted by means of variance analysis. The means were grouped by the Scott Knott test at 5% probability using the statistical software SISVAR®. According to the results obtained the shading plants in intercropped with the coffee tree managed in the post-planting and first-year phases contributed to a better coffee tree development, observed mainly in the treatments using the Crotalaria and Guandu species.Item Impacto do aumento da concentração atmosférica de dióxido de carbono sobre a ferrugem e o crescimento do cafeeiro(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2016-08) Tozzi, Fernanda Ribeiro Oliveira; Ghini, RaquelO objetivo deste trabalho foi avaliar o efeito do aumento da concentração de dióxido de carbono atmosférico sobre o crescimento de plantas e a severidade da ferrugem (causada por Hemileia vastatrix) em cafeeiro (Coffea arabica). Utilizaram-se as cultivares 'Obatã IAC 1669‐20' e 'Catuaí Vermelho IAC 144', moderadamente resistente e suscetível à doença, respectivamente. Os tratamentos consistiram de 400 e 508 μmol mol ‐1 de CO2 atmosférico, em dois tipos de estufas de topo aberto (OTC). As plantas das duas cultivares, cultivadas nas OTCs com adição de CO2 , apresentaram aumento de área foliar, e da taxa de crescimento em altura e em diâmetro do caule, em comparação às plantas cultivadas em estufas à concentração ambiente de CO2; porém, as cultivares não diferiram quanto ao teor de cera das folhas. Em 'Catuaí Vermelho IAC 144', a severidade da ferrugem diminuiu com o aumento da concentração de CO2, quanto ao número de lesões, área foliar lesionada, número de lesões esporuladas, área lesionada esporulada, percentagem de área foliar lesionada e área abaixo da curva de progresso da doença; no entanto, em 'Obatã IAC 1669‐20', a severidade da doença não variou. A incidência de folhas lesionadas por planta, o período latente, a germinação de urediniósporos e a formação de apressórios não são alterados, à dose de 508 μmol mol ‐1 de CO2, em ambas as cultivares.Item Risk analysis of climate change on coffee nematodes and leaf miner in Brazil(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2008-02) Ghini, Raquel; Hamada, Emília; Júnior, Mário José Pedro; Marengo, José Antonio; Gonçalves, Renata Ribeiro do ValleThe objective of this work was to assess the potential impact of climate change on the spatial distribution of coffee nematodes (races of Meloidogyne incognita) and leaf miner (Leucoptera coffeella), using a Geographic Information System. Assessment of the impacts of climate change on pest infestations and disease epidemics in crops is needed as a basis for revising management practices to minimize crop losses as climatic conditions shift. Future scenarios focused on the decades of the 2020’s, 2050’s, and 2080’s (scenarios A2 and B2) were obtained from five General Circulation Models available on Data Distribution Centre from Intergovernmental Panel on Climate Change. Geographic distribution maps were prepared using models to predict the number of generations of the nematodes and leaf miner. Maps obtained in scenario A2 allowed prediction of an increased infestation of the nematode and of the pest, due to greater number of generations per month, than occurred under the climatological normal from 1961–1990. The number of generations also increased in the B2 scenario, but was lower than in the A2 scenario for both organisms.