Abstract Grapes have been produced successfully in semiarid regions, but fruit quality may be affected by rootstock selection. In this study, the ‘Isabel Precoce’ grape variety was cultivated onto three different rootstocks (‘IAC 572’, ‘IAC 766’, and ‘IAC 313’), and the physicochemical traits of fruits were evaluated at 14, 19, 21 and 28 days after veraison skin. The results showed that bunches increased significantly in weight and color until 19 days after veraison. In addition, grapes accumulated soluble solids, sugars, and anthocyanins during 28 days of ripening. Moreover, the rootstock used affected bunch length, pulp firmness, and the sugar and anthocyanin contents, but it did not influence skin coloring. In conclusion, ‘Isabel Precoce’ grapes reached maximum weight at 24 days after veraison and maximum soluble solids content, titratable acidity/soluble solids ratio, anthocyanins, and total soluble sugars at 28 days. Fruit on the ‘IAC 313’ and ‘IAC 766’ rootstocks had higher total soluble solids and anthocyanins at 28 days after veraison than ‘IAC 572’. ‘Isabel Precoce grapes’ produced in semiarid conditions showed good quality for fresh marketing and for wine production.

Resumen Se han producido uvas con éxito en regiones semiáridas, pero la calidad de la fruta puede verse afectada por el porta injerto utilizado. La uva ‘Isabel Precoce’ se cultivó sobre tres porta injertos diferentes (‘IAC 572’, ‘IAC 766’ e ‘IAC 313’) y se evaluaron las características fisicoquímicas de los frutos a los 14, 19, 21 y 28 días después del envero (cuando los frutos empiezan a madurar y la piel a colorear). Los resultados mostraron que los racimos aumentaron de peso y el color de la piel cambió significativamente hasta 19 días después del envero. Además, las uvas acumularon sólidos solubles, azúcares y antocianinas durante 28 días de maduración post-envero. El porta injerto utilizado afectó la longitud del racimo, la firmeza de la pulpa y el contenido de azúcar y antocianinas, pero no influyó en la coloración de la piel. En conclusión, la uva ‘Isabel Precoce’ alcanzó el peso máximo a los 24 días del envero y la máxima calidad en contenido de sólidos solubles, relación sólidos solubles /acidez titulable, antocianinas y azúcares solubles totales a los 28 días. Los porta injertos ‘IAC 313’ e ‘IAC 766’ produjeron uvas con más azúcares solubles totales y antocianinas a los 28 días después del envero que ‘IAC 572’.

RESUMO A composição química e o estádio de maturação podem interferir no ponto de colheita do sapoti, a depender da destinação do fruto. Consequentemente, objetivou-se, com este trabalho, avaliar a influência da adubação potássica na qualidade e no potencial antioxidante do sapoti, em diferentes estádios de desenvolvimento. O experimento foi instalado na fazenda Norfruit, em Pau Branco, Mossoró, RN. O delineamento adotado foi em blocos casualizados, em esquema fatorial 5 x 6, composto por cinco doses de potássio (0, 200, 400, 600 e 800 g de K por planta) e seis estádios de desenvolvimento, com cinco repetições. Os frutos foram marcados ao atingirem 10 a 15 mm de comprimento; sendo colhidos e avaliados 90, 120, 150, 180 e 200 dias após sua marcação e completamente maduros (após oito dias de armazenamento a 25 ± 2 ºC e 58 ± 5% UR). O sapoti pode ser colhido 200 dias após a floração plena, quando atinge seu tamanho máximo e apresenta qualidade adequada para o consumo. O sapoti maduro tem maior teor de açúcares e menor concentração de compostos bioativos e atividade antioxidante. A dose de 400 g por planta de K proporciona frutos de maior massa, com maiores concentrações de polifenóis extraíveis totais e atividade antioxidante. A atividade antioxidante do sapoti está mais correlacionada com a concentração de polifenóis extraíveis totais.

ABSTRACT The chemical composition and stage of maturation may interfere with harvest point of sapodilla depending on the destination of the fruit. This study aimed at evaluating the influence of potassium fertilization on quality and antioxidant potential of sapodilla at different development stages. The experiment was carried out on farm Norfruit, in Pau Branco, Mossoró, RN. The experimental design was completely randomized blocks in a 5 × 6 factorial scheme, consisting of five doses of potassium (0, 200, 400, 600, and 800 g K for plant) and six development stages, with five repetitions. The fruits were marked when reaching 10 to 15 mm in length, being collected and evaluated after 90, 120, 150, 180, and 200 days after being marked and when they were fully mature (after eight days of storage at 25 ± 2 °C and RH 58 ± 5%). Sapodilla can be harvested 200 days after full bloom, when it reaches its maximum size and presents adequate quality for consumption. The ripe sapodilla has higher concentration of sugar and lower concentration of bioactive compounds and antioxidant activity. The dose of 400 g of K per plant generated fruits of greater mass, with higher concentration of polyphenols and antioxidant activity. The antioxidant activity of sapodilla is more correlated with total extractable polyphenol concentration.

Este trabalho teve por objetivo avaliar o efeito da cera de carnaúba (Primax Wax) e filme plástico de polietileno de baixa densidade "X-tend" sobre a vida útil pós-colheita de mamão 'Formosa' (Tainung 1) produzido em Baraúna - RN. O experimento foi conduzido no laboratório de Pós-colheita da Universidade Federal Rural do Semi-Árido (UFERSA). Utilizou-se um esquema fatorial 3 x 6 com 3 repetições de três frutos por parcela, constituindo na combinação de 3 tipos de atmosferas (cera, filme de polietileno e controle) com 6 tempos de armazenamento (0; 7; 14; 21; 28; 35). Os frutos dos distintos tratamentos foram armazenados em câmaras frias a 10 ± 2 ºC e UR 90 ± 5%, analisados em intervalos de sete dias. As características avaliadas foram: aparência externa, perda de massa, firmeza da polpa, sólidos solúveis, acidez titulável e vitamina C. Constatou-se ser o filme plástico o mais eficiente em manter a qualidade externa e reduzir a perda de massa dos frutos. A cera de carnaúba, na concentração utilizada, mostrou eficiência relativa na conservação de mamão quando comparada ao filme plástico. A vida útil pós-colheita dos frutos mantidos sob atmosfera modificada foi de 35 dias e do controle apenas 28 dias.

The aim of this work was to evaluate the effect of carnauba wax (Primax Wax) and low-density polyethylene film "X-tend" on shelf life of 'Formosa' papaya fruits produced in Baraúna, RN. The experiment was carried out in the Postharvest Laboratory of the Universidade Federal Rural do Semi-Árido (UFERSA). A 3 x 6 factorial scheme with three replications of three fruits per plot in a completely randomized design was used. The treatments consisted of the combination of three types of atmosphere (wax, polyethylene film and control) with six storage times (0; 7; 14; 21; 28 and 35). The fruits of these treatments were stored in cold chamber at 10 ± 2 ºC and RH 90 ± 5%, and analyzed in 7 days intervals. The evaluated traits were: external appearance, weight loss, pulp firmness, soluble solids, titratable acidity and C vitamin. It was observed that polyethylene film was the most efficient coverage to keep the external quality and to reduce the weight loss of the papaya fruits. The carnauba wax in the used concentration shows good efficiency in papaya fruits conservation as compared with that polyethylene film. The shelf life of papaya fruits kept under modified atmosphere was of 35 days and for those fruits kept at ambient condition was of 28 days.