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ABSTRACT. In contrast to climacteric fruits, in which ethylene is known to be pivotal, the regulation of ripening in non-climacteric fruits is not well understood. The strawberry is a typical example of a non-climacteric fruit, which has been used as a model system of these types of fruit. In this study, the effect of exogenous ethephon on the expression of ethylene biosynthesis and signaling genes, FaERF2 and FaACO1, was analyzed in the Fragaria ananassa cultivar Camino Real by quantitative real-time polymerase chain reaction, and the physicochemical and phytochemical characteristics of fruits were evaluated in field trials and postharvest tests. Transcript accumulation was influenced by exogenous treatment with ethephon, which affected the pattern of gene expression during different stages of growth and fruit development, with the highest expression occurring during postharvest tests. In addition, ethephon significantly influenced the phytochemical profile of sugars, anthocyanins, phenolic compounds, and vitamin C contents both in the field-and postharvesttreated fruits at different stages. These results indicate that ethylene regulates the phenylpropanoid maturation pathway in strawberry fruit.

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-In contrast to ripening of climacteric fruits knowledge, non-climacteric fruits ripening still poorly understood. In this sense, strawberry (Fragaria x ananassa L. Duch) is a high commercial crop and has an expressive world production that has been used as a model study. Thus, the aim of this study was to evaluate the effect on physicochemical and phytochemical characteristics of strawberry Cv. Camiño Real, in four maturation stages (green, white, pink and red) after the ethylene (Etephon®) and brassinosteroid (epi-brassinolide) exogenous spray. The evaluations were carried out at application time (field assay) and after 24h (post-harvest assay). Brassinosteroid application tends to reduce phenolic compounds content mainly in the red stage, whereas ethylene treatment tends to increase supposing that while brassinosteroids reduce phenolic compounds acting to fruit conservation, by the reduction of oxidative stress, increasing antioxidant activity, the ethylene act in fruit ripening leading to senescence. However, for vitamin C content while brassinosteroid treatment increases ascorbic acid in postharvest for the white fruit, the ethylene treatment do a dramatically increased in vitamin C content to red fruits, showing that although ethylene and brassinosteroids can affect the vitamin C content, the response can change according to the development stage spray, suggesting that more studies are necessary to understand the hormonal interaction for ascorbic acid production during strawberry ripening. Index terms: Fragaria x ananassa Duch, Rosaceae, Maturation, Ethephon, Epi-brassinolide. Efeito do etileno e do brassinoestereoide no amadurecimento do morango após aplicação no campoResumo -Em contraste com o conhecimento sobre a maturação de frutos climatéricos, a maturação de frutos não climatéricos ainda é pouco entendida. Neste sentido, o morangueiro (Fragaria x ananassa) é uma cultura de elevado valor comercial e expressiva produção mundial que vem sendo utilizada como modelo de estudos. Assim, o objetivo deste trabalho foi avaliar o efeito sobre as características físico-químicas e fitoquímicas do morango Cv. Camiño Real, em quatro estádios de maturação (verde, branco, rosa e vermelho), após o spray exógeno de etileno (Etephon®) e brassinoesteroide (epibrassinolide). As avaliações foram realizadas no momento da aplicação (ensaio de campo) e após 24 h (ensaio pós-colheita). A aplicação de brassinoesteroide reduz o conteúdo de compostos fenólicos no estádio vermelho, enquanto o tratamento com etileno aumenta. Assim, supõe-se que, enquanto os brassinoesteroides diminuem a concentração de compostos fenólicos, atuando na conservação dos frutos pela redução do estresse oxidativo e pelo aumento da atividade antioxidante, o etileno age acelerando o amadurecimento do fruto, levando à senescência. No entanto, para o conteúdo de vitamina C, enquanto o tratamento com brassinoesteroide aumenta o ácido ascórbico na pós-colheita em frutos brancos, o tratamento de etileno aumentou dramaticamente o conteúdo de vitamina C ...

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