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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Association between the artificial aging test and the natural storage of coffee seeds(Associação Brasileira de Tecnologia de Sementes - ABRATES, 2018) Fantazzini, Tatiana Botelho; Rosa, Sttela Dellyzete Veiga Franco da; Pereira, Cristiane Carvalho; Pereira, Diego de Sousa; Cirillo, Marcelo Ângelo; Ossani, Paulo CésarThe accelerated aging test is recognized as an efficient method for evaluating the vigor of seed lots and for estimating their storage potential. Thus, this work aimed to evaluate the association between artificial aging and natural storage of coffee seeds, through the correlation factor analysis. Seeds of four cultivars of Coffea arabica L. (Catuaí Amarelo, Arara, Catiguá, and Mundo Novo) and one of Coffea canephora Pierre (Apoatã) were used. Part of the newly-harvested seeds were aged in a growth chamber under controlled temperature and relative humidity conditions (42 ºC and 100% RH) for periods of 0, 4, 6, 8, and 10 days. The other part of the seeds was stored in tri-wall paper packaging for a period of 2, 4, and 6 months in a non-climate-controlled environment. Artificial aging allows predictions on the storage potential of coffee seeds, although the artificial aging periods depend on the cultivars.Item Effect of chemical treatment on the physiological and sanitary quality of stored coffee seeds(Associação Brasileira de Tecnologia de Sementes - ABRATES, 2021) Penido, Amanda Carvalho; Rodrigues, Vitor Oliveira; Carvalho, Marcos Vinícios de; Krepischi, Levi Suzigan; Pereira, Cristiane Carvalho; Oliveira, João AlmirMaintaining the health of coffee seeds is especially important during storage, as soil fungi and storage fungi can considerably reduce seed quality. Thus, chemical treatments for protection of seeds in storage becomes important in agricultural production. It is necessary to evaluate the effects of these treatments on seedling development and the protection they provide against storage fungi, aiming at seed longevity and preventing rapid deterioration. The aim of this study was to evaluate the effect of chemical treatment on the physiological and sanitary quality of stored coffee seeds. Seeds of five Coffea arabica cultivars were pre-dried, treated with Vitavax®- Thiram, and placed in cold storage at 10 °C for nine months. Seed physiological quality was evaluated every three months by the germination test and by determination of root emergence percentage, seedlings with expanded cotyledonary leaves, and seedling dry matter. Seed health quality was assessed by the health test. The chemical treatment with Vitavax-Thiram does not affect the physiological quality of stored Coffea arabica seeds. Seed treatment before storage is effective in reducing the inoculum potential of Fusarium spp. and Phoma spp. in coffee seeds.Item Physiological, biochemical, and ultrastructural aspects of Coffea arabica L. seeds under different cryopreservation protocols(Editora UFLA, 2021) Figueiredo, Madeleine Alves de; Rosa, Sttela Dellyzete Veiga Franco da; Ricaldoni, Marcela Andreotti; Pereira, Cristiane Carvalho; Coelho, Stefânia Vilas Boas; Silva, Luciano CoutinhoCryopreservation is a technique that may potentially conserve the germplasm of species of the Coffea genus for an indeterminate time. The aim of this study was to evaluate the physiological, biochemical and ultrastructural characteristics of cryopreserved seeds of Coffea arabica L., cultivar Catucaí amarelo IAC 62, which was subjected to different protocols regarding dehydration, precooling, cooling, rewarming and cathode water use. According to each protocol, the seeds were subjected to fast or slow drying to moisture contents of 17 or 20% (wet basis), cooled in different ways, and then immersed in liquid nitrogen for 24 hours. Different rewarming times in a water bath were also used. Physiological, biochemical and ultrastructural analyses were performed on the seeds after the cryopreservation steps. Moisture content at a 17% wb is the key factor for the cryopreservation of Coffea arabica L. seeds, which have better physiological quality and better preserved cell structures. Precooling of coffee seeds before immersion in liquid nitrogen does not provide advantages compared to direct immersion. The rewarming times tested (2, 4, and 6 minutes) and cathode water use did not cause changes in the physiological and biochemical quality or in the cell structures of Coffea arabica L. cryopreserved seeds. The pattern of cell structure observed in all seeds indicates that the damage from cryopreservation is less drastic in the cells of the embryos than in those of the endosperm, with the latter less tolerant to the stresses of dehydration, precooling, and rewarming.Item Tolerance of Coffea arabica L. seeds to sub zero temperatures(Editora UFLA, 2017-05) Coelho, Stefania Vilas Boas; Rosa, Sttela Dellyzete Veiga Franco da; Clemente, Aline da Consolação Sampaio; Pereira, Cristiane Carvalho; Figueiredo, Madeleine Alves de; Reis, Leandro VilelaPreservation of the quality of coffee seeds is hindered by their intermediate behavior in storage. However, long-term storage at sub zero temperatures may be achieved by adjusting the water content of the seeds. The aim of this study was to evaluate the tolerance of coffee seeds to freezing, in relation to physiological and enzymatic modifications. Coffee seeds were dried in two manners, rapid and slow, to water contents of interest, 0.67, 0.43, 0.25, 0.18, 0.11, and 0.05 g H2O g-1 dw (dry basis). After drying, the seeds were stored at a temperature of -20 oC and of 86 oC for 24 hours and for 12 months, and then compared to seeds in cold storage at 10 oC. The seeds were evaluated through calculation of percentage of normal seedlings, percentage of seedlings with expanded cotyledonary leaves, dry matter of roots and of hypocotyls, and viability of embryos in the tetrazolium test. Expression of the enzymes superoxide dismutase, catalase, and peroxidase were evaluated by means of electrophoretic analysis. Only seeds dried more slowly to 0.18 g H2O g-1 dw present relative tolerance to storing at -20 °C for 12 months. Coffee seeds do not tolerate storage at a temperature of -86 oC for 12 months. Water contents below 0.11g H2O g-1 dw and above 0.43 g H2O g-1 dw hurt the physiological quality of coffee seeds, regardless of the type of drying, temperature, and storage period. Coffee seed embryos are more tolerant to desiccation and to freezing compared to whole seeds, especially when the seeds are dried to 0.05 g H2O g-1 dw. The catalase enzyme can be used as a biochemical marker to study tolerance to freezing in coffee seeds.