Cherimoya fruit (Annona cherimola, Mill.) were kept at 20°C in air or in 20% CO 2 for 3 days and then transferred to air, to study the effect of a high CO 2 treatment on phenolic metabolism and ripening-related changes. Total polyphenol levels remained constant while a rapid decline in lignin content was observed in cherimoyas stored in air. However, a sharp increase in PAL activity up to the second day at 20°C was observed. The maximum ethylene production was observed 2 days later. At the end of the CO 2 treatment, ethylene production was inhibited and PAL activity was similar to that found in air-treated fruit. These data suggest that the increase in PAL activity at 20°C was not affected by high CO 2 and does not relate to ethylene. The CO 2 treatment inhibited flesh softening and maintained lignin at levels found in freshly harvested fruit. Exposure to 20% CO 2 also improved internal colour and increased the non-tannin polyphenol fraction, but prevented the decline in the tannin fraction otherwise observed upon ripening in air. We concluded that high CO 2 treatment at 20°C did not enhance PAL activity and lignin deposition although treated fruits retained more lignin after transfer to air. The possible involvement of PAL activity in the supply of important metabolic compounds for early events of ripening will be discussed.

O estudo visou a caracterizar frutos de goiabeira e selecionar cultivares produzidas na Região do Submédio São Francisco. Os frutos, colhidos na maturidade fisiológica, foram provenientes da Estação Experimental de Bebedouro, pertencente à Embrapa Semi-Árido e avaliados em delineamento experimental inteiramente casualizado com quatro repetições. Os tratamentos compreenderam genótipos de polpa branca (Alabama Safed, Lucknow 49, Banahas, White Selection of Florida e Seleção IPA B 38.1) e vermelha (Paluma, Patillo 2.1, Surubim, Red Selection of Florida e Seleção IPA B 14.3). Avaliaram-se: massa, diâmetro longitudinal (DL), diâmetro transversal (DT), relação DL/DT, espessura da casca, espessura da polpa, sólidos solúveis totais (SST), acidez total titulável (ATT), relação SST/ATT, pH, açúcares solúveis totais (AST) e vitamina C. Os genótipos de polpa branca, exceto Seleção IPA B 38.1, tiveram maiores massas (acima de 145,0 g). As menores relações DL/DT foram observadas em Banahas (0,98) e Lucknow 49 (1,00), caracterizando frutos redondos. Estas cultivares tiveram também maior espessura da polpa. Os maiores valores de SST foram observados em Paluma (10,4 ºBrix) e Lucknow 49 (10,9 ºBrix). A ATT foi baixa na maioria dos genótipos, exceto Surubim e Seleção IPA B 14.3, e o pH variou de 3,72 a 4,22. Em geral, os genótipos de polpa branca tiveram os maiores teores de AST (5 a 7 %) e vitamina C, atingindo 200 mg de ácido ascórbico/100 g.

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Influência de biofilmes de fécula de mandioca e amido de milho na qualidade pós-colheita de mangas 'Tommy Atkins' RESUMOO presente trabalho teve como objetivo avaliar o efeito de biofilme à base de fécula de mandioca e amido de milho na conservação pós-colheita de mangas 'Tommy Atkins'. Os frutos foram selecionados, lavados, desinfectados e revestidos com biofilmes de fécula de mandioca e amido de milho nas concentrações de 2%, 4% e 6%, e armazenados por até 21 dias a 12 ± 0,6ºC e 86% UR, mais período adicional de sete dias a 21 ± 2ºC e 67% UR. Os efeitos dos tratamentos foram avaliados por meio da perda de massa, estádio de maturação, firmeza da polpa, teor de sólidos solúveis totais, acidez titulável e pH. O delineamento experimental foi o inteiramente casualizado em esquema fatorial de 7x4 (tratamentos x período de armazenamento), com quatro repetições. Pelos resultados, verifica-se que o uso de biofilmes de fécula de mandioca a 2% e amido de milho a 4% reduziram a perda de massa, mantiveram a firmeza e melhoraram o aspecto visual, permitindo um armazenamento por mais tempo sem perda da qualidade dos frutos. Palavras-chave:Atmosfera modificada, Mangifera indica L., películas de amido.Influence of cassava starch and corn starch biofilms on the post harvest quality of 'Tommy Atkins' mangos ABSTRACTThe objective of this work was to evaluate the effects of cassava starch and corn starch biofilm on the postharvest conservation of 'Tommy Atkins' mangos. The fruits were selected, washed, disinfected and coated with cassava starch and corn starch biofilm in the concentrations of 2%, 4% and 6%, and stored for 21 days at 12 ± 0.6ºC and 86 RH, plus an additional period of 7 days at 21 ± 2ºC and 67% RH. The effects of the treatments were evaluated by mass loss, maturation index, pulp firmness, total soluble solids content, titratable acidity and pH. The experiment was carried out in a completely randomized design in 7x4 factorial scheme (treatments x storage periods), with four replications. The results indicate that the use of cassava starch at 2% and corn starch biofilms at 4% reduced the mass loss, maintained the firmness, improved the visual aspects and prolong the storage period without decreasing the fruits quality.

ABSTRACT-In perennial crops, fertilizers are applied to restore the amount of nutrient removed from the plant by harvesting. Nevertheless, the immobilized nutrient inside the whole plant should be considered. Based on it, the nutrient concentrations in the guava leaf and fruit and the nutrient contents removed by fruits and post-harvest pruning were evaluated in an irrigated orchard, in Petrolina, State of Pernambuco, Brazil. The greatest contents removed by fruits were N and K among the macronutrients, while Fe, Zn and Mn presented higher levels among the micronutrients. More than 60% of the total content of N, P, K, Mg, Fe, and B removed by pruning were immobilized in the leaf and non-marketable fruit. Index terms: Psidium guajava, mineral nutrition, foliar analysis, fruit analysis. LEVANTAMENTO DOS NÍVEIS DE NUTRIENTES