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Item Steps of cryopreservation of coffee seeds: physiological responses and antioxidant systems(Universidade Federal de Santa Maria, 2023-08-21) Souza, Ana Cristina de; Costa, Marina Chagas; Figueiredo, Madeleine Alves de; Pereira, Cristiane Carvalho; Coelho, Stefânia Vilas Boas; Vilela, Ana Luiza Oliveira; Pereira, Diego de Souza; Rosa, Sttela Dellyzete Veiga Franco daThe cryopreservation of plant germplasm at ultralow temperatures is an alternative technique for the long-term storage of seeds of the genus Coffea sp. However, for this technique to be successful, cell integrity must be maintained at all stages of the process on the basis of scientific research. The present study investigated validated cryopreservation protocols for Coffea arabica L. seeds and evaluate the effects on the physiological and biochemical characteristics of the seeds at each stage of the process. Seeds were dried on silica gel or with saturated saline solution, precooled or not in a biofreezer, immersed in nitrogen, and reheated in a water bath. After each of these steps, the physiological and biochemical quality of the seeds was determined. Pre-cooling is a step that can be dispensed with in the cryopreservation of Coffea arabica seeds, direct immersion in liquid nitrogen being more indicated. Coffea arabica L. seeds tolerate cryopreservation after rapid drying in silica gel up to water contents of 17 or 20% (wb), with greater survival at 17%. The enzyme activities of catalase, polyphenol oxidase and peroxidase are indicators of the quality of C. arabica L. seeds subjected to cryopreservation.Item Protein profile in arabica coffee seeds in electrophoresis gel: importance of freeze-drying(Associação Brasileira de Tecnologia de Sementes - ABRATES, 2022-05-13) Fávaris, Nathália Aparecida Bragança; Rosa, Sttela Dellyzete Veiga Franco da; Figueiredo, Madeleine Alves de; Coelho, Stefânia Vilas Boas; Vilela, Ana Luiza de Oliveira; Padilha, LilianCoffee seeds are sensitive to desiccation and are used or stored with different moisture content values, which may affect the results of quality assessment. The aim of this study was to evaluate the changes in protein profile in electrophoresis gel in coffee seeds with different moisture content values under freeze-drying and without freeze-drying. Two lots of arabica coffee seeds were used, one of newly-harvested seeds and another of stored seeds. The seeds were dried to the moisture content values of 12, 15, 20, 25, 30, 35, and 40%. The physiological quality of the seeds was assessed through the germination test, electrical conductivity, and the profiles of the enzymes SOD, CAT, PO, GOT, MDH, and EST and of heat-resistant proteins. In general, there is an effect on expression of these enzymes in accordance with the presence of free water in the seeds. Moist seeds have little to no enzyme expression. The freeze-drying process allows preservation of coffee seed quality and does not change the functionality of the enzymes studied. The isoenzyme profiles of the antioxidant process in arabica coffee seeds are affected by the initial moisture content of the seeds. The freeze-drying process of the seeds ensures greater sensitivity in detection of the expression of these isoenzymes.Item Exploratory studies for cryopreservation of Coffea arabica L. seeds(Associação Brasileira de Tecnologia de Sementes - ABRATES, 2017) Figueiredo, Madeleine Alves de; Coelho, Stefania Vilas Boas; Rosa, Sttela Dellyzete Veiga Franco da; Vilela, Amanda Lima; Silva, Luciano CoutinhoCryopreservation is a viable option for conservation of coffee germplasm. However, for this technique to be completely successful, it is of fundamental importance to carry out studies that ensure maintenance of cell integrity before and after immersion in liquid nitrogen (LN). Therefore, the aim in this study was to investigate the water content, cooling rate, and final temperature most suitable for cryopreservation of Coffea arabica L. seeds. The seeds were dried by silica gel to water contents of 5, 10, 15, 20, 30 and 40 % wb, subjected to slow cooling treatments at speeds of -1, -3 and -5 °C min.-1 to final temperatures of -40, -50 and -60 °C and then directly immersed in LN. After storage, seeds were rewarmed at 40 °C for two minutes. The survival rate and viability of the seeds and embryos were evaluated by the tetrazolium and germination tests. Results of the tetrazolium test indicate that embryos excised from cryopreserved seeds are less sensitive to cryopreservation than whole seeds are. The water content of 20% wb and the use of zygotic embryos led to the highest survival rate of the coffee seeds, depending on the cooling rate and the final temperature of precooling.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 Big Coffee VL.: Seed desiccation tolerance, sieve classification, and physiological quality(Editora UFLA, 2018-10) Souza, Ana Cristina de; Rosa, Sttela Dellyzete Veiga Franco da; Vilela, Amanda Lima; Figueiredo, Madeleine Alves de; Vilela, Ana Luiza de Oliveira; Stéphano Filho, Ricardo; Carvalho, Milene Alves de FigueiredoA coffee plant producing large fruit, seeds, and leaves in relation to conventional coffee plants, possibly generated by genetic mutation, was named Big Coffee VL. Seeds of this coffee plant were classified by size and used to establish the crop, whose progenies were designated as Big Coffee VL. large, Big Coffee VL. medium, and Big Coffee VL. small. The aim in this study was to investigate desiccation tolerance, together with size classification, and evaluate the physiological quality of the seeds of this progeny. Seeds of each type of Big Coffee VL. and of the cultivar Topázio were collected. High moisture seeds and seeds dried to 11% moisture content were evaluated to assess desiccation tolerance. Dried seeds of each Big Coffee VL. progeny and of the Topázio cultivar were classified by size in sieve testing using oblong screens for separation of peaberry seeds, and circular sieves from 22 to 12 for separation of flat seeds. All seeds were subjected to physiological evaluation through the germination test and determination of seedling dry matter. A completely randomized experimental design (CRD) was used; results were subjected to analysis of variance and means compared by the Scott-Knott test. Big Coffee VL. seeds tolerate desiccation to moisture content of 11% wet basis. Seeds of the Topázio cultivar have better physiological performance than seeds of the Big Coffee VL progenies. The bigger the seeds of Big Coffee VL., the better their physiological performance, exhibiting greater seedling dry matter.Item Endo-β-mannanase enzyme activity in the structures of Coffea arabica L. seeds under different types of processing and drying(Universidade Federal de Santa Maria, 2018) Ferreira, Valquíria Fátima; Ricaldoni, Marcela Andreotti; Rosa, Sttela Dellyzete Veiga Franco da; Figueiredo, Madeleine Alves de; Coelho, Stefânia Vilas Boas; Fantazzini, Tatiana BotelhoEnzymes play a fundamental role in degradation of molecules during seed germination, development, and deterioration. Endo- β-mannanase is one of the main enzymes responsible for hydrolysis of mannans in the endosperm during germination of coffee seeds through its action in hydrolytic degradation of cell walls and in weakening the structures of the endosperm that surround the embryo, allowing radicle emergence. The aim of this study was to determine the activity of the endo-β-mannanase enzyme in the structures of coffee seeds for the purpose of assessing the relationship between this activity and the physiological quality of the seeds under different processing and drying methods. Coffea arabica L. fruit in the cherry maturity stage was subjected to three different types of processing: natural (seeds maintained in the fruit itself), fully washed (fruit pulped mechanically and the seeds demucilaged by fermentation in water), and semi-washed or demucilaged (both fruit pulp and mucilage removed mechanically); and two methods of drying: slow drying (suspended screen) in the shade, and rapid drying in mechanical dryer at 35°C to a moisture content of 11±1%. After processing and drying, the physiological quality of the seeds was evaluated through the germination test, and endo-β-mannanase enzyme activity was quantified. Coffee seeds submitted to natural processing have lower physiological performance, as well as greater deterioration and greater activity of the endo-ß-mannanase enzyme. Removal of mucilage during fully washed and semi-washed processing of coffee seeds reduces the activity of the endo-ß-mannanase enzyme and lowers deterioration, especially after faster drying. The enzyme endo-ß-mannanase is efficient in studying of the effects of processing and drying on coffee seeds, and can be evaluated in whole seeds, endosperms or embryos.Item Alterações fisiológicas e bioquímicas em sementes de café secas em sílica gel e soluções salinas saturadas(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2015-06) Coelho, Stefania Vilas Boas; Figueiredo, Madeleine Alves de; Clemente, Aline da Consolação Sampaio; Coelho, Luis Filipe Serafim; Rosa, Sttela Dellyzete Veiga Franco daO objetivo deste trabalho foi avaliar alterações fisiológicas e bioquímicas em sementes de café submetidas à secagem rápida, em sílica gel, e à secagem lenta, em soluções salinas saturadas. As sementes foram secas até que atingissem os seguintes teores de água: 40, 30, 20, 15, 10 e 5% (base úmida). Após a secagem, uma parte das sementes foi imediatamente avaliada quanto ao desempenho fisiológico e ao perfil de enzimas do processo oxidativo, e outra parte foi avaliada após armazenagem em condição hermética, em câmara fria e seca, por quatro meses. A velocidade de secagem e o teor final de água tiveram efeito significativo sobre a qualidade fisiológica das sementes. Após a secagem rápida em sílica gel, as sementes toleraram teores finais de água mais baixos. No entanto, após a secagem lenta, as sementes com teores finais de água mais elevados apresentaram maior qualidade. O período de armazenamento não afetou a germinação, mas prejudicou o vigor das sementes. A secagem rápida apresenta maior potencial de dano ao endosperma do que aos embriões. O perfil enzimático das sementes de café é afetado pelo teor final de água e pela velocidade de secagem.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.