著者
Tomoki Shibuya Yuki Murakawa Koji Nishidate Manabu Nishiyama Yoshinori Kanayama
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
vol.86, no.1, pp.94-104, 2017 (Released:2017-01-31)
参考文献数
36
被引用文献数
6

切り花類の開花調節において発光ダイオードを効率的に利用するためには,単色光に対する花成や花成関連遺伝子の応答について良く理解することが必要である.長日性切り花類の花成の遠赤色光に対する応答はよく研究されているが,青色光に関する知見は少ない.すでに,長日性切り花であるシュッコンカスミソウ(Gypsophila paniculata)‘ブリストルフェアリー’の花成や FLOWERING LOCUS T と SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 のホモログである GpFT と GpSOC1 の発現が,青色光による長日処理では促進されないことが明らかとなっている.本研究では,シュッコンカスミソウ‘ミリオンスター’の花成が青色光による長日処理によって促進されたことから,シュッコンカスミソウにおいて青色光による花成応答の多様性が示唆された.そこでさらに,青色光で花成が促進された上記品種を使用し,GpFT と GpSOC1 の発現を調査した.その結果,‘ミリオンスター’の GpFT と GpSOC1 の発現は‘ブリストルフェアリー’と異なり青色光によって促進された.次に,青色光に対する花成応答に関与すると考えられる FLAVIN-BINDING KELCH REPEAT F-BOX 1 と GIGANTEA のシュッコンカスミソウホモログである GpFKF1 と GpGI を解析した.その結果,GpFKF1 と GpGI のアミノ酸配列は良く保存されており,その発現はシロイヌナズナと同様に短日と長日で異なるピークをもつ日周変動を示すこと,さらには GpFKF1 と GpGI が相互作用することが明らかとなった.一方,‘ブリストルフェアリー’と‘ミリオンスター’の 2 品種間において GpFKF1 および GpGI のアミノ酸配列には重要な違いはみられなかった.以上の結果,青色光応答の多様性は GpFKF1 および GpGI よりも GpFT および GpSOC1 に関連していることが示唆された.
著者
Yoshinori Kanayama Michiaki Omura Takeshi Goryo Tomohisa Shigeta Tomoki Shibuya Yutaka Nakai
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.OKD-109, (Released:2017-12-20)
被引用文献数
2

Brassica napus was cultivated in three test fields exposed to different radionuclide contamination levels 1.5 years after the Fukushima Daiichi nuclear power plant accident to investigate the correlation between soil contamination and radiocesium activity concentration (RCs conc.) in plants. The correlations between total and exchangeable RCs conc. were strong in the plow layer (L1) and the layer 5 cm below L1 (L2). Water-soluble radiocesium was not detected in either layer, and little radiocesium penetration was observed below L2. Correlation coefficients between RCs conc. in each plant organ and soil layers were calculated. Correlations between RCs conc. in each vegetative organ and total and exchangeable RCs conc. in L1 and correlations between vegetative organs were mostly strong during vegetative growth and flowering periods. Correlations between RCs conc. in flowers with that in L1, L2, and other vegetative organs were not significant. RCs conc. in L1 may more directly affect concentrations in roots and shoots. RCs conc. in oil extracted from seeds was measured, and the results suggested that radiocesium was not detectable in the oil fraction. Our data regarding radiocesium in soil and plants and their correlations obtained by extensive cultivation in contaminated soils could be useful to gain a better scientific understanding of radiocesium transport and accumulation and to provide useful information for the future utilization of areas with low contamination levels.
著者
Yoshinori Kanayama
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-IR01, (Released:2017-01-31)
被引用文献数
49

Sugars are strongly related to fruit yield and quality, playing a critical role in fruit set, growth, ripening, and composition. The tomato (Solanum lycopersicum) is not only an important horticultural crop, but also a useful experimental model plant that can be used to further our understanding of fruit physiology. Therefore, in this review, we consider sugar metabolism and fruit development in the tomato. We begin by discussing how the sugar content of tomato fruit has been successfully increased in a tomato introgression line containing a chromosome segment from a wild relative, and how this has furthered our understanding of the mechanism controlling sugar content. We then outline current knowledge around how sugar sensing and signaling, proton pumps, and auxin affect sugar accumulation and fruit set. The prevention of fruit abscission by auxin, which is transported by PIN auxin efflux carriers and vacuolar proton phyrophosphatase (V-PPase), may retain sucrose transport to the fruit to inhibit programed cell death (PCD) and ensure successful fruit set. There is believed to be a trade-off between fruit sugar content and yield. However, fruit size and yield do not appear to decrease in the tomato introgression line IL8-3 and sucrose-induced repression of translation (SIRT)-engineered tomatoes, which contain higher fruit sugar contents. Future research needs to investigate the factors involved in sugar sensing and signaling, in addition to the sugar metabolic enzymes that have previously been studied for horticultural applications.
著者
Hiroki Ikeda Tomoki Shibuya Manabu Nishiyama Yoshihiro Nakata Yoshinori Kanayama
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-015, (Released:2016-09-28)
被引用文献数
20

Calcium (Ca2+) concentration, early fruit growth, and expression of Ca2+-movement-related genes were analyzed during early fruit development in the tomato, which is the most important stage regarding the incidence of blossom-end rot (BER), to investigate the physiological mechanisms affecting the occurrence of BER. We used tomato introgression line IL8-3 with a chromosome segment from a wild relative (Solanum pennellii) because this line shows lower incidence of BER compared with the parent cultivar ‘M82’ (S. lycopersicum), as described previously. Ca2+ concentration in fruit and leaves was higher in IL8-3 than in ‘M82’, whereas no significant differences were observed between Ca2+ concentration in roots and stems of ‘M82’ and IL8-3. These results suggested that a Ca2+ transport property is an essential factor for the lower incidence of BER in IL8-3. IL8-3 fruit showed a lower growth rate than ‘M82’, which could result in preventing the occurrence of BER. The expression of genes encoding cation exchangers, Ca2+-ATPases, a Ca2+ channel, and Na+/Ca2+ exchangers, was higher in IL8-3 fruit than in ‘M82’ fruit, suggesting active Ca2+ movement in IL8-3. All results in this study could be related to physiological mechanisms accounting for the lower incidence of BER in IL8-3.
著者
Tomoki Shibuya Yuki Murakawa Koji Nishidate Manabu Nishiyama Yoshinori Kanayama
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-126, (Released:2016-06-02)
被引用文献数
6

The flowering response to monochromatic light and flowering-related genes underlying this response need to be characterized to efficiently use light-emitting diodes for lighting culture. The flowering response to far-red light has been well studied in long-day cut flowers, but there have been few studies investigating the response to blue light. Flowering and the expression of the G. paniculata homologs of the FLOWERING LOCUS T and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 genes (GpFT, GpSOC1) were not previously promoted in Gypsophila paniculata, an important long-day cut flower, ‘Bristol Fairy’ under long-day conditions with blue light. In the present study, we found that flowering was promoted in another G. paniculata ‘Million Star’, under long-day conditions with blue light, suggesting that there is variation in G. paniculata’s flowering response to blue light. Therefore, we analyzed the expression of GpFT and GpSOC1 in the ‘Million Star’. The expression of GpFT and GpSOC1 was promoted with flowering in ‘Million Star’ under long-day conditions with blue light in contrast to ‘Bristol Fairy’. We next analyzed the G. paniculata homologs (GpFKF1, GpGI) of FLAVIN-BINDING KELCH REPEAT F-BOX 1 and GIGANTEA genes, which participate in the flowering response to blue light. GpFKF1 and GpGI amino acid sequences were well conserved; gene expression showed a diurnal rhythm with different peaks under short-day and long-day conditions, as previously observed in Arabidopsis thaliana. GpFKF1 interacted with GpGI. There were no important differences in GpFKF1 or GpGI amino acid sequences between the two cultivars. Our results suggest that variation in the flowering response to blue light is associated with GpFT and GpSOC1, rather than GpFKF1 and GpGI.
著者
Yasushi Kawasaki Satoshi Matsuo Yoshinori Kanayama Koki Kanahama
出版者
園芸学会
雑誌
Journal of the Japanese Society for Horticultural Science (ISSN:18823351)
巻号頁・発行日
pp.MI-001, (Released:2014-09-03)
被引用文献数
4 23

Low-cost heating is needed to reduce chilling injuries, heating costs, and CO2 emission during greenhouse tomato production. To acquire information about the physiological and morphological effects of root-zone heating, an economical option at low air temperatures, we grew tomato plants on a nutrient film technique hydroponic system in a heated nutrient solution. We investigated the effects of short-term root-zone heating after transplanting and long-term heating until harvest. We measured short-term plant growth, nutrient uptake, root activity (xylem exudation and root respiration rates), root indole-3-acetic acid (IAA) concentration, internal root structure, and long-term fruit weight and dry matter distribution. The minimum root-zone temperature was maintained at 16.6°C, while the minimum air temperature (5.9°C) and the minimum root-zone temperature in the control (5.8°C) were lower than optimal. After 7 days of root-zone heating, root dry weight and relative growth rate increased compared with those of the control, accompanied by increased mineral nutrient uptake and xylem exudation. These changes may explain the increased shoot growth after 21 days of heating. In roots, development of the epidermis and stele, including the xylem, was promoted by heating, in contrast to previous research on root-zone cooling at high air temperature, which promoted xylem-specific development. Although the proportion of dry matter distributed to the fruit was not changed by root-zone heating, individual fruit size and total yield were higher than in the control due to a higher total dry weight in the heating treatment. Our results suggest that root-zone heating is an effective low-cost heating technology at low air temperature because of its effects on root activity, growth, and fruit yield, but that the mechanisms may differ from those in root-zone cooling at high air temperature.