Efeito da reidratação e do hipoclorito de sódio na germinação de sementes e emergência de plântulas de cafeeiro

• Autor(a) principal: Lima, Júlien da Silva
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/4479
• topic: Café; Sementes; Hipoclorito de sódio; Pergaminho; Emergência; Coffee; Seeds; Sodium hypochlorite; Endocarp; Emergence; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA

This work was carried out at the UFV s Seed Research Laboratory and EPAMIG s Plantlet Production Nursery in Viçosa, Minas Gerais, to evaluate the effect of sodium hypochlorite on endocarp degradation of re-hydrated coffee seeds and the effect of this degradation on seed germination and plantlet emergence. One sample of seeds of the cultivar Catuaí Vermelho IAC 44 with moisture degree of 12, 16 and 20% was re-hydrated in running water up to 33% and another sample remained at the initial moisture degree. All the seeds (re-hydrated or not) were pre soaked in aqueous solution of sodium hypochlorite at the concentrations of 0, 3, 4 and 5% of active chlorine over 3 h and washed in running water over approximately 90 seconds. To each initial moisture degree were added two treatments: seeds with endocarp (used by nursery workers) for 3 hours and with endocarp removed by hand. The experiment I tests were carried out to evaluate seed germination under laboratory conditions and the experiment II tests evaluated plantlet emergence percent and velocity under nursery conditions. At the nursery, the seeds were sown in substrate constituted by soil + dry manure, at the rate of 7:3 (v:v). Manual endocarp removal favored seed germination and plantlet emergence in the coffee plants. The use of sodium hypochlorite did not provide efficient results under laboratory conditions. Seed immersion with water initial content of 12, 16 and 20% in sodium hypochlorite aqueous solution at concentrations of 3, 4 and 5% was not effective when endocarp was manually removed in increasing and accelerating plantlet emergence, under nursery conditions. Re-hydration before and after seed immersion in sodium hypochlorite aqueous solution was not efficient in in improving plantlet emergence.