Ciência Rural
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/10366
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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 Chemical analyses of flowers and leaves for nutritional diagnoses of coffee trees(Universidade Federal de Santa Maria, 2021) Zabini, André Vinicius; Martinez, Herminia Emilia Prieto; Neves, Júlio César Lima; Cruz, Cosme Damião; Valadares, Samuel VasconcelosThe chemical analysis of flowers has been studied for some crops. In coffee trees, the flower tissue analysis could anticipate the nutritional diagnosis. This study aimed to: (i) compare the mineral composition of coffee flowers and leaves; and to (ii) generate reference values for nutritional diagnosis of coffee trees, based on flower and leaf analysis. Nutrient content of flowers and leaves and coffee productivity were evaluated in 26 commercial farms located in Manhuaçu, MG, Brazil throughout three years. The critical nutrient content range in Flowers are respectively: 2.78 – 3.17, 0.23 – 0.28, 2.80 – 3.12, 0.30 – 0.37, 0.24 – 0.30, 0.15 – 0.18 dag kg-1 of N, P, K, Ca, Mg, and S; and 17 – 21, 12 – 18, 52 – 80, 26 – 43, and 28 – 48 mg kg-1 of Zn, Cu, Mn, Fe, and B. For leaves, the critical nutrient ranges are respectively: 2.63 – 2.86, 0.13 – 0.14, 2.13 – 2.33, 1.04 – 1.22, 0.27 – 0.33, 0.15 – 0.18 dag kg-1 of N, P, K, Ca, Mg, and S; and 9 – 14, 15 – 23, 80 – 115, 99 – 148, and 31 – 37 mg kg-1 of Zn, Cu, Mn, Fe, and B. The nutritional diagnosis of coffee trees for N, P, Ca, Fe, Cu, and Mn can be anticipated using flower analysis.Item Selection of arabica coffee progenies tolerant to heat stress(Universidade Federal de Santa Maria, 2015-07) Teixeira, Alexsandro Lara; Souza, Flávio de França; Pereira, Antonio Alves; Oliveira, Antonio Carlos Baião de; Rocha, Rodrigo BarrosDue to high temperatures, practically all coffee farms in the state of Rondonia are of the C. canephora species. Thus, importing arabica coffee from other states becomes necessary for composition of blends, as well as for the specialty or gourmet coffee market. The purpose of this study was to select arabica coffee genotypes that exhibit satisfactory agronomic performance under high temperature conditions. The experiment was conducted in Ouro Preto do Oeste, RO, Brazil, with mean annual temperature of 25.8°C and mean annual rainfall of 2300mm year -1 . The experiment was composed of 114 arabica coffee genotypes, with 103 progenies and eleven control cultivars, provided by EPAMIG. A randomized block experimental design was used with three replications, spacing of 3.0x1.0 meters and five plants per plot. All the crop seasons showed significant difference for the green coffee yield trait. In joint analysis, significant differences were detected among progenies and control cultivars. In the average of the four harvests, green coffee yield was 32.38 bags ha -1 . The cultivars ‘Catuaí Vermelho IAC 15’, ‘Obatã IAC 1669-20’ and ‘Catucaí Amarelo 2SLCAK’ stood out, achieving yields greater than 40 bags ha -1 . The gain obtained from selection was 14.33 bags ha -1 , which is equivalent to an increase of 44.04% in production of green coffee. The progeny H514-7-10-6-2-3-9 stood out with an average yield of 51.20 bags ha -1 . In regard to maturation cycle, 56% of the progenies were classified as early maturity and 44% as medium maturity. Late maturity genotypes were not observed.Item Eficiência de utilização de nutrientes por cultivares de cafeeiro(Universidade Federal de Santa Maria, 2011-04) Amaral, José Francisco Teixeira do; Martinez, Herminia Emilia Prieto; Laviola, Bruno Galvêas; Fernandes Filho, Elpidio Inácio; Cruz, Cosme DamiãoElucidar as diferenças nas exigências nutricionais entre as cultivares é uma forma de obter maior produtividade e otimizar o uso de fertilizantes. Este trabalho teve por objetivo avaliar a eficiência na produção de raiz e parte aérea por unidade absorvida de N, P, K, Ca, Mg, S, B, Cu e Zn em quatro cultivares de cafeeiro arábico (‘Acaiá IAC-474-19’, ‘Icatu Amarelo IAC-3282’, ‘Rubi MG-1192’ e ‘Catuaí Vermelho IAC- 99’). Para tanto, foi conduzido um experimento em condições de campo, no Campus da Universidade Federal de Viçosa, durante dois anos, em delineamento experimental de blocos casualizados, em arranjo fatorial 4x3, constituído de quatro cultivares e três níveis de adubação (baixo, normal e alto), com quatro repetições. As plantas que constituíram o nível normal receberam adubação baseada na marcha de acúmulo de nutrientes em café arábica. Nos níveis de adubação baixo e alto, as plantas receberam, respectivamente, 0,4 e 1,4 vezes a recomendação de adubação feita para o nível normal. A eficiência de utilização de nutrientes para produção de raízes foi diferenciada entre as cultivares quando houve restrição na quantidade de adubos fornecidos (nível baixo), não havendo diferenças entre elas quando se empregou dose normal e alta de fertilizantes. A eficiência na produção de raízes por unidade de N, P, K, Ca, Mg e S absorvidos foi maior na cultivar ‘Acaiá IAC-474-19’ e menor na ‘Rubi MG-1192’. Conclui-se que a eficiência de utilização de nutrientes para produção de raízes e uso de nutrientes pela parte aérea de cafeeiros foi diferenciada entre cultivares.Item Alterations in antioxidant metabolism in coffee leaves infected by Cercospora coffeicola(Universidade Federal de Santa Maria, 2016-10) Andrade, Camila Cristina Lage de; Vicentin, Rayssa Pereira; Costa, Josineide Rodrigues; Perina, Fabiano José; Resende, Mario Lúcio Vilela de; Alves, EduardoBrown eye spot (BE) caused by Cercospora coffeicola is the main disease of coffee crop. A variation in symptoms of BE has been reported in the field, raising suspicion of occurrence of new species. However, information about coffee-C. coffeicola interaction is still limited. This research aimed to determine the difference between antioxidant metabolism of coffee plants cultivar Mundo Novo inoculated with a strain isolated from a common BE lesion (CML 2984) and a strain isolated from a black BE lesion (CML 2985). The enzyme activity of peroxidase (POX), catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) were determined. Activities of POX, APX, and PAL increased in plants inoculated with both strains compared to non- inoculated plants at 12 and 24 hours post inoculation (hpi). CAT activity increased in inoculated plants with black BE strain at 24 hpi and both strains at 48 hpi. The SOD activity only increased in inoculated plants with both strains at 48 hpi. These results show that an elevated antioxidant response was observed when the plants were challenged with both strains of C. coffeicola. Both strains produced lesions of the common type, suggesting that other factors lead to the development of black BE lesion type under field conditions and further investigation is needed.Item Quality of mechanized coffee harvesting in circular planting system(Universidade Federal de Santa Maria, 2013-01) Cassia, Marcelo Tufaile; Silva, Rouverson Pereira da; Chioderolli, Carlos Alessando; Noronha, Rafael Henrique Freitas; Santos, Edvaldo Pereira dosMechanized coffee harvesting is one of the main technological advances that benefit producers, but problems with planning for planting and crop development and faults in harvester adjustment can reduce the efficiency of the operation, making it more stressful for the crop than manual harvesting. Thus the present study was carried out in the municipality of Patos de Minas, MG, Brazil with the objective of assessing the damage in the vegetable part and the quality of the mechanized harvesting of coffee cropped in a circular planting system under a center pivot, with two rod vibration frequencies and statistical control of the process. It was observed that the negative biennially on the crop reduced the initial coffee load eliminating the effects of the insolation conditions. The harvest quality indices were distributed asymmetrically and the samples varied greatly and only the stripping efficiency was influenced by the axles assessed and were shown to be stable by the statistical control. The damage to the plants by the harvester presented desirable values and did not vary in function of the factors analyzed, but was considered under statistical control.