Longevidade de pimenta ornamental (Capsicum annuum L.) sob estresse de temperatura e luz

• Ano de defesa: 2012
• Autor(a) principal: Cavatte, Rithiely Paschoa Queiroz
• Orientador(a): Finger, Fernando Luiz
• Banca de defesa: Moreira, Marialva Alvarenga , Pinto, Cleide Maria Ferreira , Ramos, Paula Acácia Silva
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Fisiologia Vegetal
• Departamento: Controle da maturação e senescência em órgãos perecíveis; Fisiologia molecular de plantas superiores
• País: BR
• Palavras-chave em Português: Etileno; 1-MCP; Luz; Antocianina
• Palavras-chave em Inglês: Ethylene; MCP-1; Light; Anthocyanin
• Área do conhecimento CNPq: CNPQ::CIENCIAS BIOLOGICAS::BOTANICA::FISIOLOGIA VEGETAL
• Link de acesso: http://locus.ufv.br/handle/123456789/1005

Some post production factors are obstacles for the commercialization of horticultural products, affecting directly the colorfulness and quality of plants, depreciating the final quality of the product. I addition to evaluate the light and temperature action on the leaf longevity of ornamental pepper (Capsicum annuum L.), analyzing the mechanisms of protection and efficacy of 1-MCP (1-methylcyclopropene) to reduce the effects of the stresses during transport, this experiment studied the behavior of two ornamental peppers under stress. In the first experiment it was simulated the transportation of the plants on the dark (DT) and with light (LT); shipping of the plants previously treated with 1-MCP under dark (DM) and light (LM). In all the treatment the plants were kept at 35 ± 2°C for 48 hours. The 1-MCP was applied at concentration of 1 μL L-1 withing a 90 L container for 6 hours. In the second experiment, it was compared the responses of the two varieties under light at temperatures of 35oC and normal temperature of 25oC. The temperature of 35 oC induced leaf abscission on the plants by increasing the ethylene production and/or sensitivity. The use of 1-MCP drastically reduced the leaf abscission in both varieties when exposed to high temperature. The response to the 1- MCP was dependent on the variety and light conditions in which the plants were maintained. The temperature of 35 oC did not affect the leaf membranes integrity in both varieties. Only in the plants of the variety BGH 1039 without 1-MCP treatment under light there was membrane damage. The 1-MCP applied to BGH 1039 plants kept under light was able to induce carotenoid synthesis and increase the concentration of total chlorophyll on the treatments DM and LM for the BGH 1039 and Roxa, respectively. In addition to the leaf abscission, the temperature of 35 oC reduced the green color of the leaves in the BGH 1039 kept under dark. The period of 48 hours at 35oC reduced the starch level in the leaves of the plants. These conditions favored the accumulation of non-reducing sugars in the plants with higher leaf abscission (DT and LT for the BGH 1039 and Roxa), indicating induction of senescence. In order to keep the post production quality of the ornamental pepper kept under stress, it is necessary to breed viiiand select varieties with higher concentration of anthocyanins and efficient anti oxidative response system.