Prolongamento da vida pós-colheita de flores de Asystasia gangetica T. Anders com soluções de tiossulfato de prata
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Data
2001-04-27
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Universidade Federal de Viçosa
Resumo
Visando-se estudar a eficiência de técnicas de preparação da solução de tiossulfato de prata (TSP) no prolongamento da vida pós-colheita de flores de Asystasia gangetica, bases de secções de ramos florais de aproximadamente 0,20 m de comprimento foram imersas naquelas soluções de prata (0,5 mol m^-3), por 60 min, e as secções posteriormente transferidas para copos de vidro com água de torneira. Tratamentos de pulverização das flores com soluções de TSP e de nitrato de prata também foram efetuados. Soluções de TSP prepara das pelas técnicas propostas foram capazes de bloquear o efeito do Ethrel (composto liberador de etileno) na abscisão floral mais eficientemente do que as soluções tradicionais. Quando aplicadas em forma de pulverização ou em imersão direta dos botões, as soluções de AgNO3 e TSP foram igualmente eficientes em inibir a ação do Ethrel. Soluções de TSP preparadas pelas técnicas propostas e armazenadas por períodos de até 69 dias, em frascos escuros, em geladeira, mostraram -se mais eficientes no prolongamento da vida pós-colheita das flores do que as soluções preparadas pelos modos tradicionais. Quando preparadas em água de torneira, as soluções de TSP foram bastante eficazes, independentemente do nível de cloreto de potássio (até 115 mg L^-1). Água de torneira, portanto, pode ser utilizada no preparo de soluções de TSP. Atribuindo-se uma pontuação arbitrária à eficácia das soluções de TSP nos vários experimentos executados, tornou-se possível classificar as diversas técnicas de preparação, em ordem decrescente: Cristais – Lento (solução de nitrato de prata vertida vagarosamente sobre cristais sólidos de tiossulfato de sódio), Cristais Invertido – Lento (solução de tiossulfato de sódio vertida vagarosamente sobre cristais sólidos de nitrato de prata), Cristais In vertido – Rápido (solução de tiossulfato de sódio vertida rapidamente sobre cristais sólidos de nitrato de prata), Solução Tradicional – Rápido (solução de nitrato de prata vertida rapidamente sobre a solução de tiossulfato de sódio) e Solução Tradicional – Lento (solução de nitrato de prata vertida lentamente sobre a solução de tiossulfato de sódio). Em seguida veio a solução de nitrato de prata puro; obviamente o menor efeito no prolongamento da vida pós-colheita das flores foi produzido com o controle, i. e, tratamento das estacas com água destilada pura.
With the objective of studying the efficiency of the techniques of preparation of silver thiosulphate solutions (TSP) for prolonging post-harvest life of Asystasia gangetica flowers, the basal parts of floral branch sections 0,20 m long were immersed into those silver solutions (0,5 mol m^-3) for 60 minutes, The sections were afterwards transferred to glass cups containing tap water. Flowers were also sprayed with TSP and silver nitrate solutions. Solutions of TSP as prepared by the proposed techniques were observed to block the action of Ethrel (an ethylene releasing compound) in flower abscission more promptly than solutions prepared by the traditional ways. The silver nitrate and TSP solutions were equally efficient in inhibiting the Ethrel action, when either applied to flower buds by spraying or by their direct immersion into solutions. Solutions of TSP as prepared through the proposed techniques and stored for different periods (up to 69 days) in dark flasks, in a common freege, were kept a greater efficiency in prolonging flower post- harvest life rather than solutions prepared by the traditional ways. When prepared with tap water, TSP solutions were quite effective, irrespective of the levels of chloride ions (up to 115 mg L^-1). Tap water therefore can thus be recommended in for the preparation of silver thiosulphate solutions. If an arbitrary score as based in the efficiency of the TSP solutions as prepared by the several techniques, in the experiments here performed, a classification of them in decreasing order was obtained as followed: Crystals – Slow (the silver nitrate solution was slowly poured on solid crystals of sodium thiosulphate); Inverted Crystals – Slow (solution of sodium thiosulphate was slowly poured on solid crystals of silver nitrate); Inverted Crystals – Fast (solution of sodium thiosulphate was fastly poured on solid crystals of silver nitrate); Traditional Solution – Fast (solution of silver nitrate was fastly poured on to the solution of sodium thiosulphate); and Traditional Solution – Slow (solution of silver nitrate was slowly poured on to the solution of sodium thiosulphate). The next are was the solution of pure silver nitrate. The smallest effects in the prolongation post-harvest life of flowers were produced treatments with pure water.
With the objective of studying the efficiency of the techniques of preparation of silver thiosulphate solutions (TSP) for prolonging post-harvest life of Asystasia gangetica flowers, the basal parts of floral branch sections 0,20 m long were immersed into those silver solutions (0,5 mol m^-3) for 60 minutes, The sections were afterwards transferred to glass cups containing tap water. Flowers were also sprayed with TSP and silver nitrate solutions. Solutions of TSP as prepared by the proposed techniques were observed to block the action of Ethrel (an ethylene releasing compound) in flower abscission more promptly than solutions prepared by the traditional ways. The silver nitrate and TSP solutions were equally efficient in inhibiting the Ethrel action, when either applied to flower buds by spraying or by their direct immersion into solutions. Solutions of TSP as prepared through the proposed techniques and stored for different periods (up to 69 days) in dark flasks, in a common freege, were kept a greater efficiency in prolonging flower post- harvest life rather than solutions prepared by the traditional ways. When prepared with tap water, TSP solutions were quite effective, irrespective of the levels of chloride ions (up to 115 mg L^-1). Tap water therefore can thus be recommended in for the preparation of silver thiosulphate solutions. If an arbitrary score as based in the efficiency of the TSP solutions as prepared by the several techniques, in the experiments here performed, a classification of them in decreasing order was obtained as followed: Crystals – Slow (the silver nitrate solution was slowly poured on solid crystals of sodium thiosulphate); Inverted Crystals – Slow (solution of sodium thiosulphate was slowly poured on solid crystals of silver nitrate); Inverted Crystals – Fast (solution of sodium thiosulphate was fastly poured on solid crystals of silver nitrate); Traditional Solution – Fast (solution of silver nitrate was fastly poured on to the solution of sodium thiosulphate); and Traditional Solution – Slow (solution of silver nitrate was slowly poured on to the solution of sodium thiosulphate). The next are was the solution of pure silver nitrate. The smallest effects in the prolongation post-harvest life of flowers were produced treatments with pure water.
Descrição
Palavras-chave
Crescimento e desenvolvimento de plantas, Pós colheita, Tratamento com tiossulfato de prata
Citação
ANJOS, Ubaldo José Costa dos. Prolongamento da vida pós-colheita de flores de Asystasia gangetica T. Anders com soluções de tiossulfato de prata. 2001. 54 f. Dissertação (Mestrado em Fisiologia Vegetal) - Universidade Federal de Viçosa, Viçosa. 2001.