著者

Masahiro Kamimori Takeshi Isobe Hiroshi Yakushiji

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

vol.91, no.3, pp.337-344, 2022 (Released:2022-07-21)

参考文献数

27

被引用文献数

1

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We aimed to determine the suitability of ‘Reikodai 1 go’ (BC1 from interspecific hybridization of Ficus carica L. and F. erecta Thunb.) as a ceratocystis canker disease-resistant rootstock for ‘Masui Dauphine’ fig. In this study, ‘Masui Dauphine’ was grafted onto ‘Reikodai 1 go’ and grown in 45 L pots under artificial soil infestation with Ceratocystis ficicola Kajitani et Masuya. Ceratocystis canker resistance, tree growth, and fruit production was assessed by comparing scion growth and fruit production in ‘Reikodai 1 go’-grafted and ‘Masui Dauphine’ own-rooted trees. No significant differences in the initial growth of the shoots (first year of planting) was observed between ‘Reikodai 1 go’-grafted and own-rooted trees. ‘Reikodai 1 go’-grafted trees demonstrated a tendency towards scion overgrowth. Soil inoculation with C. ficicola (nine times in three years; 2 L of suspension with 105 conidia/mL per pot) resulted in the death, or inhibited growth, of own-rooted trees. However, inoculated ‘Reikodai 1 go’-grafted trees revealed no growth inhibition and had growth similar to those of non-inoculated own-rooted and non-inoculated ‘Reikodai 1 go’-grafted trees. These results suggest that ‘Reikodai 1 go’-grafted trees were highly resistant to soil infestation with C. ficicola. No significant differences were observed between ‘Reikodai 1 go’-grafted trees with or without C. ficicola inoculation in terms of fruit production (considering fruit set, date of maturation, fruit length, width, fruit weight, estimated yield, skin color, and soluble solids content). When comparing fruit production of ‘Reikodai 1 go’-grafted and own-rooted trees, no differences were observed between the two in terms of fruit characteristics. Therefore, the use of ‘Reikodai 1 go’ as a rootstock is unlikely to cause considerable problems in the fruit production of ‘Masui Dauphine’ fig trees. Overall, shoot growth and fruit production of ‘Masui Dauphine’ grafted onto ‘Reikodai 1 go’ were not significantly different from those of the own-rooted trees. Therefore, it is expected that the introduction of ‘Reikodai 1 go’ rootstock for ‘Masui Dauphine’ production will be an effective approach for controlling ceratocystis canker.

著者

Atsu Yamasaki Hiroshi Yakushiji Hajime Iwamoto Akifumi Azuma Hiroyoshi Sugiura

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-039, (Released:2017-03-17)

被引用文献数

4

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Various on-tree ethanol-sticker treatments for ‘Taigetsu’ and ‘Taiten’ persimmon (astringent cultivars) were tested to identify optimal treatment conditions for astringency removal and fruit quality. Using aluminum foil coated or polyethylene terephthalate stickers to attach a pad containing 1.5 g of ethanol powder to both sides of the fruit surface in early October removed astringency completely, while the application of treatments to one side of the fruit surface did not. The astringency removal was incomplete in treatments with a cast coating sticker. The aluminum foil-coated sticker with a 1.0 g ethanol pad applied in early October removed flesh astringency completely without fruit skin darkening or the occurrence of large numbers of brown specks in the flesh. It extended fruit shelf life by approximately 7 days compared with postharvest CO2 treatment in November. Conversely, sticker treatments in late September caused many brown specks in the flesh. The sticker treatment with a 0.6 g ethanol pad failed to remove the astringency completely while the sticker treatment with a 1.5 g ethanol pad resulted in heavy fruit skin darkening or the appearance of shallow concentric cracks on the fruit skin. Therefore, we conclude that an on-tree sticker treatment with a 1.0 g ethanol pad on both sides of the fruit surface in early October removes fruit astringency completely and provides high quality ‘Taigetsu’ and ‘Taiten’ persimmon fruit.

著者

Yasuhisa Tsuchida Hiroshi Yakushiji

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-040, (Released:2016-11-22)

被引用文献数

5

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With the continuing trend of global warming, the adverse impact of high temperature and the inevitably accompanying drought stress on the growth of Japanese apricot trees (Prunus mume Siebold et Zucc.) are of concern. Therefore, the effects of these factors on photosynthesis and carbohydrate translocation were analyzed. An investigation was conducted at average daytime temperatures of 24°C, 30°C, and 34°C under both irrigated and drought conditions. The 34°C temperature was higher than the open air temperature by 5°C. Stable isotope 13C was administered to trees to determine carbohydrate positioning. Under the drought stress condition, the photosynthetic rate declined accompanied by temperature elevation, and at the highest temperature of 34°C, 13C concentrations in the twigs and roots were lower than those in the irrigated trees at 24°C. Two-way analysis of variance revealed a trend of 13C translocation to the young organs above ground, and old organs, while roots were affected by water status, temperature, and their combination, respectively. In the irrigated trees, the photosynthetic rate reduction was not detected, even at higher temperatures. However, translocation incompetence reflecting a decline in 13C concentration in the roots was observed at 34°C. These results indicate that the permissible diurnal average temperature during summer for the growth of Japanese apricot trees is approximately up to 30°C, and in the temperature range around this irrigation is helpful to facilitate regular functioning of carbohydrate translocation under drought stress conditions.

著者

Hiroshi Yakushiji Atsu Yamasaki Shozo Kobayashi Junko Kaneyoshi Akifumi Azuma Hiroyoshi Sugiura 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.MI-080, (Released:2015-12-29)

被引用文献数

4

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‘Hasshu’, a dwarf budsport that originated from the leading persimmon cultivar ‘Hiratanenashi’ (Diospyros kaki Thunb.), was discovered in Japan in 2005. Although ‘Hiratanenashi’ is seedless because of anisoploidy (2n = 135 = 9x), ‘Hasshu’ produces some small normal seeds. In this study, we investigated differences in the morphological characteristics of the vegetative organs and fruits and in the ploidy level between ‘Hasshu’ and ‘Hiratanenashi’. The shoot length, internode length, and leaf size of ‘Hasshu’ were smaller than those of ‘Hiratanenashi’. ‘Hasshu’ bore smaller flowers than those of ‘Hiratanenashi’ in late May, and had consistently smaller fruit than ‘Hiratanenashi’ at all fruit development stages. ‘Hasshu’ ripened in late October, similar to ‘Hiratanenashi’. Both ‘Hiratanenashi’ and ‘Hasshu’ are pollination-variant astringent (PVA) cultivars. Except for the deletion of one allele at ssrdk10, no differences were detected between the two cultivars at four simple sequence repeat (SSR) marker loci. By flow cytometric analysis and chromosome observation, we confirmed that ‘Hasshu’ was octoploid (2n = 120 = 8x), indicating that it was both a dwarf and a ploidy-reduction mutation. These results suggest that recovery of the ability to produce some normal seeds by ‘Hasshu’ may have been caused by the change in ploidy from anisoploid to isoploid.