P.I. Garriz, G.M. Colavita, H.L. Alvarez , V. Blackhall
Maturity at harvest is one of the primary factors affecting quality of ‘Braeburn’ apples (Malus × domestica Borkh). Prematurely picked fruit are small, poorly coloured and lacking flavour; furthermore, the risk of developing the browning disorder is greater. Fruit that are picked too late soften prior to subsequent marketing and are more susceptible to internal breakdown. Because of the large economic impact for growers, the optimal picking period should be accurately determined, based on changes of maturity indicators. The objective of this work was to investigate harvest date effects on flesh firmness (FF), starch pattern index (SPI) and soluble solids concentration (SSC) from initial commercial harvest (ICH) for five weeks, over three growing seasons, in the Rio Negro High Valley region of Argentina. The study was conducted on ‘Braeburn’ apple trees on M.IV rootstock, planted in 1993, trained to palmette leaders and spaced 4.02.3 m. Fruit were collected weekly at the orchard of the Comahue National University (lat. 38°56’S, long. 67°59’W). Relative humidity, sunshine duration and temperature were monitored during the experimental period. Data were evaluated by analysis of variance and means were compared using Tukey’s range test. ICH occurred between 167 and 169 days after full bloom. The range of values for FF, SPI and SSC at ICH were 91.1-94.2 N, 2.7-3.3 and 11.2-11.8Brix, respectively, for the three years. Fruit softened markedly with advancing harvest date, with significant differences (P<0.05) between fruit harvested at ICH compared with those obtained four weeks later. FF did not differ between years. Starch content gradually decreased as the fruit matured, implying starch was converted into soluble sugars and therefore SSC increased substantially during the sequential harvests. Season significantly affected SPI and SSC. Further studies are needed to assess ‘Braeburn’ fruit maturity for optimizing harvesting time in diverse environmental conditions.
Garriz, P.I., Colavita, G.M., Alvarez , H.L. and Blackhall, V. (2012). MATURITY OF 'BRAEBURN' APPLE FRUIT AS AFFECTED BY HARVEST TIMING AND SEASON. Acta Hortic. 932, 245-250
DOI: 10.17660/ActaHortic.2012.932.35
Malus × domestica Borkh., flesh firmness, harvest date, soluble solids concentration, starch pattern index

Acta Horticulturae