Cellular compartmentation and membrane permeability to sugars in relation to early or high temperature-induced watercore in apples

Comparison of the sub-cellular compartmentation of sugars in mature apples of two cultivars susceptible to different types of watercore and grown in different climates

“…The results were similar to those in previous observations at Ehime when early (or high temperature-induced) watercored 'Orin' fruit from the outer canopy were compared with nonwatercored 'Orin' fruit from the inner canopy, from the immature to the mature stage (Yamada et al, 2006b). In contrast to results at the immature stage (Yamada et al, 2006a), the glucose contents of mature watercored 'Orin' fruit were slightly, but significantly, lower than those of mature non-watercored 'Fuji' fruit at Ehime, which may reflect cultivar differences in sorbitol and/or glucose metabolism during maturation. Significantly lower and higher distributions of sorbitol in the vacuoles and in the cytoplasm, respectively, were detected in watercored 'Orin' at Ehime than in non-watercored 'Orin' at Aomori, and in 'Fuji' at Ehime (Figure 3).…”

“…The compartmental analysis method (Macklon and Higinbotham, 1970;Pallaghy and Scott, 1969) was used to determine the content of each sugar in the vacuoles, the cytoplasm, and the intercellular spaces (Yamada et al, 2006a;Yamaki and Ino, 1992). When logarithmic values for the content of each sugar remaining in the discs of fruit flesh after each period of incubation were plotted against incubation time, the linear part of the efflux curve indicated the release of sugar from the vacuoles ( Figure 1A).…”

Non-Destructive Global and Localized 2D T1/T2 NMR Relaxometry to Resolve Microstructure in Apples Affected by Watercore

“…The apple at the bottom has 45.71 % of affected tissue and a much localized damage region. Peaks are assigned as 1 for vacuole 2 and 3 for cytoplasm and extracellular water Yamada et al (2006Yamada et al ( , 2012, who found that in watercored apples, the permeability of the tonoplast increases especially to sorbitol, and they also found a higher permeability of the plasma to other sugars, such as fructose, glucose and sorbitol. This means that if there is an increase of the permeability of the membrane, diffusion between different compartments will be easier.…”

“…In mild cases, watercore symptoms may disappear during storage, but in more severe cases when the fruit is stored for a long time, it may undergo anaerobiosis and develop alcoholic flavours or suffer internal breakdown and browning (Bennedsen and Peterson 2005;Dart and Newman 2005). Watercore symptoms are also related to a metabolic change in sugar composition (Bowen and Watkins 1997;Yamada et al 2006;Melado-Herreros et al 2013a), which makes watercore apples especially appreciated in some regions of Asia and Spain. It is regarded as an added value because of their sweet and juicy flesh (Dart and Newman 2005;Kasai and Arakawa 2010;Melado-Herreros et al 2013a).…”

Physiological Roles of Polyols in Horticultural Crops

“…The relationship between sorbitol catabolism and transport and watercore should also be investigated. Gao et al (2005) suggested that decreased expression of a sorbitol transporter results in late watercore in apple fruit, while Yamada et al (2006aYamada et al ( , 2006b found active metabolism and uptake of sorbitol in parenchyma cells of early watercored apple fruit. …”