Teste LERCAFÉ: adequação e aplicação para avaliar a qualidade de sementes de cafeeiro (Coffea arabica L.)

• Ano de defesa: 2007
• Autor(a) principal: Zonta, João Batista
• Orientador(a): Araújo, Eduardo Fontes
• Banca de defesa: Silva, Fernando Antônio Pereira da , Dias, Luiz Antonio dos Santos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Fitotecnia
• Departamento: Plantas daninhas, Alelopatia, Herbicidas e Resíduos; Fisiologia de culturas; Manejo pós-colheita de
• País: BR
• Palavras-chave em Português: Café; Sementes; Hipoclorito de sódio; Teste rápido
• Palavras-chave em Inglês: Coffee; Seeds; Sodium hypochlorite; Rapid test
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA
• Link de acesso: http://locus.ufv.br/handle/123456789/4657

The objective of this work was to evaluate the application of the LERCAFÉ test to estimate germination and characterize different types of injuries/deterioration in coffee seeds and to determine new combinations of concentration of sodium hypochlorite, imbibition time and temperature-time exposure to make the LERCAFÉ test even more economical and faster. The experiments were conducted at the Seed Research Laboratory of the Federal University of Viçosa. Three experiments were carried out using seeds of coffee variety Catuaí IAC 44. The experiment I included seeds with 33, 28, 23, 18 and 13% of tenors of water (wet basis) stored in impermeable packages at 20±3ºC. Seeds were evaluated through the tests of germination and LERCAFÉ, in which the percentages of germinated and non-germinated seeds were calculated and deterioration during storage characterized. The LERCAFÉ test consisted of imbibition of seeds without parchment in solution of 2.5% active chlorine for 3 hours at 25ºC in BOD, using 100 mL of sodium hypochlorite solution per 50 seeds or corresponding volume. Seeds were then washed in running tap water and soaked in distilled water for 40 minutes. The tests were carried out at 4 storage times: zero, two, four and six months. In the experiment II, the seeds were subjected to different types of damages, and the treatments consisted of non-damaged seeds, seeds with mechanical damage, heat damage (at 40 and 60ºC) and bug damage. Seeds were then evaluated by tests of germination and LERCAFÉ (same as experiment I), calculating the percentages of germinated and non-germinated seeds and characterizing the deterioration during storage. In the experiment III, the seeds were evaluated by the tests of germination and LERCAFÉ by calculating the percentages of germinated and non-germinated seeds. The following treatments were applied: imbibition in solution of sodium hypochlorite in water at the concentrations of 2.5; 3.5 and 4.5% of active chlorine, imbibition times of 1, 2 and 3 hours, at 25, 30 and 35ºC. In all the treatments, the seeds had the parchment manually removed and were stored in gerboxes with screen, soaked in sodium hypochlorite in the proportion of 100 mL of solution per 50 seeds or corresponding volume at temperatures, imbibition times and concentrations according to the treatments. Following the imbibition times, seeds were washed in running tap water and soaked in distilled water for 40 minutes. In the experiment I, germination decreased with storage for all the tested moisture contents. The LERCAFÉ test showed larger percentages of seeds with clear endosperm when evaluated before storage (high germinative power) and larger percentages of seeds with dark endosperm (brown or black) at the six months of storage (low germinative power). The germination estimated by the LERCAFE test had high correlation (r>0.99) with the values from the germination test. The results obtained from the experiment II showed that the LERCAFÉ test is efficient to estimate germination and characterize the different types of injuries in coffee seeds. The germination results estimated by the LERCAFÉ test had high correlation with the results from the germination test for the three types of injuries. The mechanical damage was characterized by a fissure in the embryo region and/or in the region opposed to the embryo, with a green stain surrounding the fissure borders. The heat damage, by drying seeds at 40 and 60ºC, was characterized by scattered green stains, partially or totally covering the seed endosperm. A sunken lesion surrounded by a green ring characterized the damage by coffee berry borer. In the experiment III the combinations 2.5% of active chlorine, at 35ºC, for 3 hours and 3.5% of active chlorine, at 30ºC, for 2 hours, were efficient to estimate seed germination, indicating the possibility of reducing the time for carrying the test out.