Cell walls of loosening skin in post-veraison grape berries lose structural polysaccharides and calcium while accumulate structural proteins

The effects of trunk girdling and crop load levels on skin color, juice composition, and root elongation of a red table grape, ‘Aki Queen’ (Vitis labrusca L. × V. vinifera L., tetraploid) were investigated. The treatment of a low crop load with girdling significantly elevated the anthocyanin concentration in berry skin compared to that of a high crop load without girdling. The total soluble solid content of berries was significantly greater in a low crop load with girdling than in other treatments. Titratable acidity was not different among treatments. Root elongation stopped for two weeks as a result of the girdling treatment, regardless of the crop load level. Root elongation after girdle healing was vigorous when the crop load was low.

/pdf/zhao-guo-liang-tohuan-zhuang-hakupi-gabudou-an-yun-kuin-2x9k5nygdx.pdf

着果量と環状はく皮がブドウ‘安芸クイーン’の果実品質および根の伸長に及ぼす影響

SummaryCommon sea buckthorn, Hippophae rhamnoides L. (Elaeagnaceae), is a small fruit tree widely distributed throughout Europe and Asia. Because H. rhamnoides plants are actinorhizal and tolerant of abiotic stresses, they grow in nutritionally-poor environments where it is difficult to grow other crops. Furthermore, sea buckthorn is rich in vitamins, unsaturated fatty acids, and phenolic compounds, and is used for medicinal purposes and as food in some parts of the World. In this review, we discuss (i) the pharmaceutical efficacy of H. rhamnoides; (ii) research on the sugars and acids contents of H. rhamnoides fruit, because it is part of the diet in some cultures and also shows promise as a functional food; and (iii) the various fruit phenotypes of sea buckthorn found in India and Russia because a high level of genetic diversity is important for improving fruit quality and yield. Few reviews on the medicinal and nutritional properties of H. rhamnoides have been published in the field of horticultural sc...

Research progress on the medicinal and nutritional properties of sea buckthorn (Hippophae rhamnoides) – a review

SummaryFruit growth of Japanese pear ‘Kosui’ was promoted by GA treatment, but suppressed by CPPU treatment. The number of cells smaller than 200 microns was fewer in GA-treated fruits but more in CPPU-treated fruits, while the number of cells larger than 200 microns was in contrast to this. Sucrose content in the fruits was higher in GA-treated fruits, but glucose and fructose content was higher in CPPU-treated fruit. Therefore, while sucrose preferentially accumulates in Japanese pear ‘Kosui’ with more large cells induced by GA treatment, glucose and fructose preferentially accumulate in fruits with more smaller cells, as a result of CPPU treatment.

Effects of GA and CPPU treatments on cell size and types of sugars accumulated in Japanese pear fruit

Solute Accumulation by Grape Pericarp Cells III. Sugar Changes in vivo and the Effect of Shading

The grape berries accumulate sugar very rapidly around 4 weeks before ripening. In order to clarify the mechanism of this sugar accumulation in Delaware grape berries during Stage III, changes in sugar and organic acid content in the growing berries, effects of the number of leaves retained on and time of complete removal of leaves from a bearing shoot on sugar content in the berries, changes in sugar content in the berries detached from the shoot at Stage III, and the conversion of polysaccharides or organic acids into reducing sugars in the berries were investigated.(1) The major sugars in the grape berries were glucose and fructose. These sugars contained totally about 2% in the fresh immature berries, wheras they were about 17% in the mature berries. The ratio of glucose to fructose in the berries changed during the period from bloom to maturity. Glucose in the berries was more predominantly accumulated than fructose during the green color and the early ripening stage of their growth. This relation was reversed at the later ripening stages.(2) As in most fruits, malic acid is present in grape berries. In contrast to them, however, a large amount of tartaric acid contains in the berries, which is the characteristic of this genus. The concentrations of malic acid and tartaric acid in the berries were highest in the beginning of Stage III and the amount of both acids in the berries decreased markedly during the ripening stage, but another peak of tartaric acid concentration was found in the beginning of Stage I.(3) There were no differences in sugar content of the berries on the shoot with 8 leaves or more, as compared to that of the berries on the control shoot, but the berries on the shoot less than 8 leaves had less sugar content. Even the berries on the shoot completely defoliated still accumulated about 6% of reducing sugars.(4) During Stage III, the accumulation of reducing sugars in the berries was found even after complete removal of leaves from the shoot together with girdling at both sides of the node where the cluster was attached.(5) When the enzymes extracted from the berries during Stage III were added into the insoluble substrate prepared from the berries during Stage I, reducing sugar content in the incubation buffer solution increased.(6) When 14C-malic acid was fed into the berries of Stage III through the pedicel for 2 hours in a liquid form, 31% of incorporated 14C was found in the sugar fraction.From these results, it was cleared that the translocation of photosynthates synthesized in the leaves into the berries was most important for the rapid sugar accumulation in grape berries, and also, the translocation of sugars converted from polysaccharides in shoots into the berries and the conversion of polysaccharides and organic acids in the berries themselves into reducing sugars were found to be related to the accumulation as well.

Physiological studies on the ripening of Delaware grapes. II. Effect of the light intensity at the cluster on sugar accumulation and carbon dioxide fixation in the berries under light and dark conditions.

K. Yonemori

Papers

Physiological studies on the ripening of Delaware grapes. II. Effect of the light intensity at the cluster on sugar accumulation and carbon dioxide fixation in the berries under light and dark conditions.