- 著者
- Toshihiko Sugiura Mikio Shiraishi Shohei Konno Akihiko Sato
- 出版者
- 一般社団法人 園芸学会
- 雑誌
- The Horticulture Journal (ISSN:21890102)
- 巻号頁・発行日
- pp.OKD-061, (Released:2017-04-26)
- 被引用文献数
- 12
To develop a method for predicting the skin color of grape berries of three cultivars of Vitis labrusca L. × Vitis vinifera L. grown in Japan, we investigated the relationship between skin color and air temperature in the grape production areas of 18 prefectures. When mean air temperature during the 40 days before harvest date was ≥24°C, the skin color ratings of ‘Kyoho’, ‘Pione’, and ‘Suzuka’ were significantly negatively correlated with temperature. Skin color ratings decreased by about 1 unit per 1°C increase; at a given mean air temperature during this period, the rating of ‘Suzuka’ was higher (by 0.7 units) than that of ‘Kyoho’, which was higher (by 1.0 unit) than that of ‘Pione’. Because an approach to predict harvest date has not been established, we developed a method to predict skin color at harvest based on air temperature after the full-flowering date. We found the times that had a strong negative correlation between the mean air temperature and the skin color rating at harvest was 43 days from 50 DAF (days after full flowering) for ‘Kyoho’, 46 days from 46 DAF for ‘Pione’, and 42 days from 52 DAF for ‘Suzuka’. We obtained a linear regression equation for the relationship between the skin color rating at harvest and the mean air temperature during the periods. If the full-flowering date is known, it is possible to predict skin color at harvest by using this equation and the predicted air temperature after full flowering. We also developed a method for predicting anthocyanin contents in berry skins at harvest using significant regressions among the skin color rating, the skin anthocyanin content, and mean air temperature.
- 著者
- Mikio Shiraishi Hideaki Asakuma
- 出版者
- The Japanese Society for Horticultural Science
- 雑誌
- The Horticulture Journal (ISSN:21890102)
- 巻号頁・発行日
- pp.UTD-023, (Released:2018-11-23)
- 被引用文献数
- 1
We monitored sugar accumulation profiles and developmental changes in fruit traits during the ripening process in pollination-constant non-astringent (PCNA)-type persimmon cultivars of ‘Akiou’, ‘Fuyu’ and ‘Taishuu’. As the fruit ripened, transverse and longitudinal diameter, fruit weight, soluble solids content (SSC), and flesh juiciness increased significantly, with a constant varietal ranking throughout the ripening process. Color development of ‘Akiou’ and ‘Taishuu’ seemed to be faster than that of ‘Fuyu’ during the initial stages of fruit ripening, but there was little difference in color chart values toward the latter stage of fruit ripening. Flesh firmness decreased steadily over time, whilst varietal ranking remained constant. The varietal ranking of SSC in the latter stage of ripening was ‘Akiou’ ≥ ‘Taishuu’ > ‘Fuyu’. Significant varietal differences were observed in sucrose, glucose, and fructose contents. Based on sugar accumulation profiles, the cultivars could be classified into two types: hexose accumulators (‘Taishuu’) and sucrose accumulators (‘Akiou’ and ‘Fuyu’). The transcriptional profiles of key sugar accumulation-related genes: sucrose synthase (SuSy), vacuolar acid invertase (VAI), and sucrose phosphate synthase (SPS), were also examined. Transcriptional levels of SuSy and VAI in sucrose accumulators were lower than those in the hexose accumulator. Conversely, transcriptional levels of SPS were higher in the sucrose accumulators than in the hexose accumulator. In particular, the concomitant and rapid increase of both SPS expression and sucrose accumulation in mid-October, suggests that this period is crucial for ‘Akiou’ in terms of the SSC elevation.