著者
Ittetsu Yamaga Atsushi Ikegaya Shigekazu Nakamura Shigehiro Yamazaki Teruko Nakajima
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-261, (Released:2021-04-21)
被引用文献数
1

To prevent the decay of satsuma mandarin fruit during the distribution process, we investigated the effect of ultraviolet-C (UV-C) irradiation and temperature treatment (TT) on scoparone (a phytoalexin) production in fruits. To this end, the fruits were maintained at 20°C for 24 h following irradiation, and then the scoparone content was measured after export to Singapore by sea freight or after domestic storage. The scoparone content in the flavedo of TT fruits significantly increased for 24 h after UV-C irradiation, compared with that in the flavedo of non-TT fruits. In fruits exported in reefer containers (0°C), the scoparone content in the TT fruits was 59.1 μg·g−1FW, whereas that in non-TT fruits was 15.1 μg·g−1FW. The domestically stored fruits showed similar trends to those of the exported fruits. The scoparone content in domestically stored fruits was higher than that in the exported fruits because the storage temperature was higher than the temperature in the reefer container used for export. There was a significant difference in the decay rate between UV-C-irradiated and non-irradiated fruits. These results showed that UV-C irradiation was effective in reducing the decay of fruits exported by sea, and TT before storage induced scoparone production in the flavedo, even under cold storage.
著者
棚瀬 幸司 小野崎 隆
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
vol.85, no.3, pp.254-263, 2016
被引用文献数
6

<p>花持ちとエチレン感受性が異なるポットカーネーション品種を用いて定量 PCR による解析を行った.'ポラリス'の花持ちは'アリエル'(対照品種),'オレンジデュオ','レモンソフト'よりも有意に長かった.'ポラリス'の花のエチレン生成量は低く,これはエチレン生合成関連遺伝子(DcACS1 と DcACO1)の発現抑制に起因していた.老化関連遺伝子(DcCP1,DcbGal,DcGST)は'アリエル','オレンジデュオ','レモンソフト'では花弁老化時に発現上昇が見られたが'ポラリス'では非常に低いままであった.これらの結果から,'ポラリス'におけるエチレン生合成関連遺伝子の抑制によるエチレン低生成機構は花持ちに優れる切り花品種'ミラクルルージュ'と'ミラクルシンフォニー'と同一であることが示唆された.全ての品種でエチレン生合成関連遺伝子(DcACS1,DcACO1)と DcCP1,DcbGal,DcGST1,DcEIL3 は外生エチレン処理により発現誘導されたが,'オレンジデュオ'と'レモンソフト'は'アリエル'と'ポラリス'に比べ,外生エチレン処理後の花弁のインローリングが遅れて起こり,外生エチレンに対する感受性が低かった.これらの結果から,エチレン感受性が低い品種では,花弁のインローリングに関係する因子のみ変化していることが示唆された.</p>
著者
Sneha Sharma Panmanas Sirisomboon Pimpen Pornchaloempong
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-168, (Released:2020-07-14)
被引用文献数
3

To date, different approaches have been applied to measure the internal parameters of mangoes by destructive and non-destructive techniques. Recently, real-time evaluation of the internal parameters has become important assessment for fruits in high demand. This research aims to develop an online prototype system to measure the total soluble solids (TSS) in mangoes using a fiber optic diode array Visible-Near Infrared (Vis-NIR) spectrometer on a conveyor belt. Spectra were acquired in a wavelength range from 400–1000 nm. The diffuse reflectance spectra of mangoes were subjected to several preprocessing techniques such as moving average smoothing (MAS), standard normal variate (SNV), multiplicative scatter correction (MSC), baseline offset and normalization before model development. The spectral information and corresponding TSS values were used to establish a linear relationship by partial least squares (PLS) regression. Spectra in three wavelength ranges of 400–1000 nm, 600–1000 nm, and 700–1000 nm were used for the model development. Baseline offset combined with MAS showed effective transformation of spectra at a wavelength of 600–1000 nm. The optimum model was obtained by an external validation technique with a correlation coefficient of calibration set and a prediction set of 0.80 and 0.74, respectively. The root mean square error of the calibration (RMSEC), root mean square error of prediction (RMSEP) and bias were 0.690%, 0.765%, and 0.061%, respectively. The statistical results from PLS regression indicated the feasibility of using the online conveyor system for grading the fruit according to the TSS.
著者
Md Asaduzzaman Toshiki Asao
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-R009, (Released:2020-03-11)
被引用文献数
11

Strawberry plants are grown in hydroponics for higher quality and yield, as this system excludes soil-borne disease issues. Recycled hydroponics is practiced to make cultivation cost-effective, sustainable, and environmentally friendly. However, due to recycling of hydroponic nutrient solution, plant root exudates accumulate, leading to autotoxicity, a form of allelopathy that inhibits growth and development. In recent decades, commercial cultivation of strawberry under greenhouse and plant factory conditions following recycled hydroponics has been widely adopted globally. Subsequently, yield decline has also been reported due to development of autotoxicity from the accumulated root exudates. In recycled hydroponic systems, strawberry plant growth is inhibited by root exudates that contain mainly phenolic acids in the culture solution. In this regard, elimination of these accumulated root exudates or allelochemicals from the culture solution would restore inhibited plant growth and yield. A number of research studies have been conducted on autotoxicity in strawberry and possible mitigation methods. These studies suggested that addition of activated charcoal in the nutrient solution, supplementation of auxin on leaves, electro-degradation of root exudates in nutrient solution, and supplementation of amino acids and/or LEDs can effectively remove/degrade/mitigate autotoxicity in strawberry grown under recycling hydroponics. This review mainly discusses the autotoxicity phenomenon in strawberry under recycled hydroponics, the responsible allelochemicals and their mechanism of action, mitigation methods and future research endeavors in this field.
著者
Sho Ohno Maiko Ueno Motoaki Doi
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-097, (Released:2019-11-15)
被引用文献数
9

Anthocyanin in pepper is beneficial as a food antioxidant compound and as a pigment for ornamentals, while unexpected anthocyanin accumulation in fruit, known as black spots, reduces the commercial quality of some cultivars. Previous studies demonstrated that the Anthocyanin (A) locus determines the anthocyanin accumulation in pepper fruits, and an MYB transcription factor, CaMYBA, was found to be located near the A locus. However, the causal gene sequence of the A locus has not yet been identified. With progress regarding genome information in pepper, two other homologous MYB genes were found to be located near CaMYBA, and they are also considered to be candidate genes for the A locus. In this study, we attempted to identify the causal gene sequence of the A locus by performing linkage analysis, genomic sequence analysis, and gene expression analysis of the three candidate MYB genes. A crossing experiment between pigmented ‘Peruvian Purple’ and non-pigmented cultivars confirmed that anthocyanin accumulation in the pigmented cultivar was controlled by a single locus. Gene expression analysis demonstrated that a basic helix-loop-helix transcription factor, CaMYC, and CaMYBA were expressed abundantly in pigmented cultivars, but the other two MYB genes were not. Genotyping of the F2 population derived from the cross demonstrated that the anthocyanin accumulation phenotype was highly linked to CaMYBA, but not to CaMYC. The DNA sequence of CaMYBA in pigmented cultivars had an insertion of a 4.3 kb retrotransposable element LINE-1 in the first intron, but that of non-pigmented cultivars did not. No pigmented cultivar-specific sequence was found in the promoter region of CaMYBA. Therefore, it was suggested that CaMYBA, but not the other two homologous MYB genes, is the A locus gene, and insertion of LINE-1 in CaMYBA appeared to be important for the regulation of anthocyanin accumulation, although the mechanism by which the LINE-1 insertion induces CaMYBA expression is unknown.
著者
Evelyn Villanueva Nozomi Fujibayashi-Yoshii Suguru Matsuzaki Kazuki Yamazaki Chairat Burana Kenji Yamane
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
vol.88, no.2, pp.276-283, 2019 (Released:2019-04-23)
参考文献数
23
被引用文献数
7

The postharvest physiology of cut astilbe inflorescences (Astilbe × arendsii), which consist of many small florets with a short vase life, was studied in response to treatments to extend their vase life. Exogenous ethylene treatment at 0.3 μL·L−1 for 7 h did not affect the senescence of inflorescences or leaves of five cultivars and 0.2 mM silver thiosulfate for 2 h did not improve the quality of inflorescences of three cultivars, which indicated that ethylene is not a critical factor for senescence in astilbe florets. Continuous treatment with 2% sucrose or 2% trehalose solutions prolonged the cut inflorescence vase life of one or two of five astilbe cultivars, respectively. Pulse treatment with 2% trehalose in combination with 6% sucrose increased total soluble sugar contents from 11.4 to 57.6 mg·g−1 FW and raised the respiration rate of inflorescences from 15.3 to 28.4 μmol CO2·h−1·g−1 FW at 2 days after harvest (DAH) in the cultivar ‘Gloria Purpurea’. However, the effects of pulse treatment diminished at 4 DAH and extended the vase life from 4.0 days to a maximum of 5.6 days, which suggested that pulse treatments were inadequate to maintain sugar contents and respiration activity. Continuous treatment with 6% sucrose extended the vase life from 4.3 to 10.0 days and raised the chroma (C*) value of florets from 28.7 to 54.9 at 8 DAH. Continuous treatment with 2% trehalase + 4% sucrose markedly prolonged the vase life to 11.5 days and increased the C* value to 53.9 at 8 DAH. Under stereomicroscopic observation, continuous treatment with 2% trehalase + 4% sucrose maintained more vivid pink color of petals, styles, filaments and receptacles than those in control florets at 9 DAH. Combined treatment with 2% trehalose and 30 μM validamycin A, a potent inhibitor of trehalose metabolizing activity, induced severe wilting of florets and necrotic spots on leaves. Exogenous trehalose may be hydrolyzed by trehalose metabolizing activity in cut astilbe inflorescences. The results suggest that continuous treatment with trehalose and sucrose solutions is effective to maintain development and delay senescence of florets to extend the vase life of cut astilbe inflorescences.
著者
Akemi Ohmiya Masaya Kato Takehiko Shimada Kenji Nashima Sanae Kishimoto Masayasu Nagata
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-R003, (Released:2019-03-12)
被引用文献数
26

Carotenoids are isoprenoid pigments, which are widely distributed in nature. In fruits and flowers, carotenoids are responsible for bright yellow, orange, and red colors and provide a substrate to form flavor compounds, which attract pollinators and seed dispersers. In leaves, carotenoids play an essential role in photosynthesis. When carotenoids are ingested in the diet, they play a vital role in human nutrition and health as a precursor of vitamin A, antioxidants, and anti-inflammatory agents. It is therefore important to control carotenoid accumulation to improve the commercial value of horticultural crops. Carotenoid accumulation is regulated by flux through the carotenoid biosynthetic pathway, and also by degradation and sequestration into plastids, which function as sink organelles. These processes are mostly controlled at the transcriptional levels of relevant genes. In this review, we summarize recent advances in studies on the molecular mechanisms that regulate carotenoid accumulation in vegetables, fruits, and ornamental flowers.
著者
Misaki Ishibashi Shunji Okochi Kazuyoshi Sone Yuji Noguchi Yuichi Uno
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-051, (Released:2019-03-07)
被引用文献数
5

Strawberry (Fragaria × ananassa) contains a major allergen, Fra a 1, which causes oral allergic syndrome. Fra a 1 is a PR-10 homolog that is regulated by environmental conditions. The allergenicity of fruit caused by Fra a 1 may depend on the genotype or growing conditions. We analyzed the Fra a 1.01 transcript levels and Fra a 1.01 protein levels in strawberry fruits of several genotypes across all seasons. In the preliminary rough screening, we selected the line WH1 bearing white fruit and the red-fruited cultivar ‘Akihime’. Under the same environmental conditions, there was no significant difference in Fra a 1.01 levels between the two cultivars over several months, suggesting that receptacle color was not indicative of allergenicity caused by Fra a 1.01. Fruits cultivated under the same environmental conditions should be used for comparisons of the allergenicity among genotypes. Both ‘Akihime’ and WH1 accumulated significantly higher levels of Fra a 1.01 protein in winter than in spring. We investigated the effects of irradiation and low temperature as environmental factors controlling the accumulation of Fra a 1.01 in winter. A shading treatment on fruit did not significantly affect Fra a 1.01 protein accumulation in strawberry fruits. Regarding variations over time, the Fra a 1.01 protein content was higher in fruits harvested at midnight in January than in those harvested at other times and in other months. These findings suggested that the Fra a 1.01 protein accumulates in response to environmental factors such as cold stress.
著者
Masashi Yamamoto Natsuki Nishiguchi Atsushi Shimada Ryoji Matsumoto
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-050, (Released:2019-03-02)
被引用文献数
6

In this study, we cultivated 32 major citrus cultivars and local accessions of Kagoshima and one control accession to elucidate the polymethoxylated flavone contents with the purpose of providing information for citrus consumers to promote citrus production in the region. All trees were grafted on trifoliate orange rootstock and cultivated in Kagoshima City, Japan. In general, the Brix values and fruit weights of the major cultivars were higher and heavier than those of the local accessions. The ascorbic acid content of Tankan and Rokugatsu Mikan was high and that of Shiikuwasha, Kabuchii, and Shiikuu was very low. For analysis of polymethoxylated flavones (PMF), important health-promoting components sinensetin, nobiletin, heptamethoxyflavone, and tangeretin were quantified. Cultivar and accession differences in the PMF content were also observed. Nobiletin and tangeretin were found to be major PMF in most accessions, and heptamethoxyflavone was not detected in some species such as Kishu Mikan, Ponkan, Shiikuwasha, and Kuroshima Mikan. In the major cultivars, the PMF contents of Kishu Mikan, Ponkan, and Tankan were found to be high. In the local citrus accessions, Shiikuwasha, its relative, and Kishu Mikan were found to have the highest PMF content, and those of Kabuchii and Kuroshima Mikan were also high. Major cultivars Satsuma mandarin, pummelo, and its relative and the local accession Kunenbo contained little PMF.
著者
Fraidoon Karimi Takashi Baba Satoshi Noma Daiki Mizuta Jin Gook Kim Manabu Watanabe Megumi Ishimaru Takuya Ban
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.OKD-129, (Released:2019-02-14)
被引用文献数
2

Moderately vigorous shoots of mature rabbiteye blueberry ‘Tifblue’ bushes were pruned in summer to clarify the effects on vegetative and reproductive traits. Treatments included un-pruned, 25% pruned (removing 25% of the shoot length), 50% pruned (removing 50% of the shoot length) and 75% pruned (removing 75% of the shoot length). Vegetative and flower bud number per shoot decreased with increasing pruning severity. Consequently, the number of laterals per shoot dropped. However, lateral length increased with increasing pruning severity. Shoots pruned at 75% produced a small number of laterals, but they were the most vigorous. Pruning severity induced the transition of vegetative buds to reproductive buds in areas lower than the cut position. The flower bud number per shoot decreased with increasing pruning severity. However, yield per shoot was not affected due to a compensatory increase in berry weight. Total soluble solids content and titratable acidity of the berry juice, as well as, the number of berries per flower bud were not affected. Hence, to reduce the unproductive parts of the plant, and to produce bigger berries, September removal of either 50% or 75% of the length of mature rabbiteye blueberry shoots under conditions similar to the Kanto region of Japan is recommended.
著者
Megumu Takahashi Takayoshi Ohara Fumio Sato Yuka Nakano Hidekazu Sasaki
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-018, (Released:2019-02-14)
被引用文献数
4

Axillary buds of broccoli (Brassica oleracea L. var. Italica) develop and produce lateral heads after the apical heads have been harvested; however, lateral heads are not used because of their small size, and only one apical head is generally harvested from one plant. In this study, we aimed to establish a new method to harvest two heads of 12 cm diameter from a plant by pinching the apical bud and growing two axillary buds (“V-shaping” process) in autumn cropping. First, we measured the probability of axillary bud generation (PA) at each leaf axil and calculated the integration of the PA (IPA). The PA from the 5th to 8th true leaves was especially high, and the IPA reached 4.7. Next, we investigated the period of harvest and yield of heads at different times (3rd, 5th, 7th, 9th, 11th, 13th, and 15th leaf stage) of V-shaping in Field 1 (Ibaraki Prefecture, Tsukuba City). In V-shaped plots from the 7th to 11th leaf stages, the number of marketable heads significantly increased in comparison to that of the control. It increased by 61% of that of the control at the 11th leaf stage. However, the period of harvest was delayed, and the quality of heads deteriorated by cold injury when V-shaping was conducted from the 11th stage onward. Finally, we assessed the applicability of V-shaping cultivation in other fields. V-shaping was conducted from the 9th to 11th leaf stage. The number of marketable heads increased by 69 and 62% in Field 2 (Ibaraki Prefecture, Tsukubamirai City) and Field 3 (Nara Prefecture, Uda City), respectively. However, it only slightly increased in Field 4 (Mie Prefecture, Tsu City). Comparison of cultivation conditions at these 4 fields revealed that early transplantation, to allow an approximate 300°C day increase in effective heat unit summation for harvesting before the daily minimum temperature fell below approximately 0°C, was important. In addition, improving the drainage of the field seems important, and the input of manure compost (long-term fertilizer effect) may improve the quality and yield of heads. Thus, we concluded that V-shaping cultivation enabled the harvesting of two heads by V-shaping and increased the number of marketable heads by more than 60% in a wide area.
著者
Kim Hyun Jin Kim Jongyun Yun Do Lee Kim Ki Sun Kim Yoon Jin
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
vol.85, no.4, pp.360-365, 2016
被引用文献数
5

<p>コチョウランにおける植え込み培土の差異が生育と開花に及ぼす影響を検討するため,コチョウラン品種'ドリテノプシス クイーンビアー 満天紅'を 4 種類の植え込み培土(チリ産ミズゴケ,培土用ピートモス,培土用ベイマツ由来バーク堆肥とピートモスを 3:7 で混和した培土,チリ産ミズゴケとピートモスを 4:6 で混和した培土)でそれぞれ 15 か月栽培し,その生育状況を観察した.4 種類の培土の物理性(間隙率と保水力)と化学性(pH と EC)を調査したところ,液肥灌水をした 3 日目までは,ミズゴケ+ピートモス混合培土の体積含水率は,他の培土に比べて有意に優れていた.またバーク堆肥+ピートモス混合培土は他の培土に比べて土壌間隙率は低く維持された.体積含水率と土壌間隙率の変化は成長反応と関連性はなかったが,'満天紅'のシュートの成長と着花はピートモス培土でより促進された.おそらく pH 6.15 という適切な pH 条件下において,十分な水分と肥料の供給が培土を通じて地中の根から植物体に吸収されたことに起因すると考えられる.移植後 15 か月目には,ピートモス培土とバーク堆肥+ピートモス混合培土における植物体の成長は,他の培土に比べて葉は大きく,乾物重も大きかった.ピートモス培土で生育した植物体は,1 株当たり 2.75 本の花茎(穂状花序)を形成し,一方,他の培土では 2.00~2.33 本の花茎を形成した.ピートモス培土では 67%,バーク堆肥+ピートモス混合培土では 33%,ミズゴケ培土では 17%,ミズゴケ+ピートモス混合培土では 8%の植物体が 3 本の花茎を形成し,3 本立ちとなった.培土の違いのおける総開花数については統計学的に有意差はなかったが,総花蕾数に関しては,1 本当たりピートモスが 32.3 個,ミズゴケが 23.4 個,バーク堆肥+ピートモス培土が 23.0 個,ミズゴケ+ピートモス培土が 19.7 個であった.花茎(穂状花序)の出現時期については,ピートモス培土が他の培土に比べて短縮された.これらの結果から,コチョウランの栽培にピートモスを含む培土を用いることで,生産者はより安価な培土で葉の成長と蕾の形成を促進することができ,結果的により高い収益性を生み出しうるコチョウラン品種'満天紅'の高品質生産が可能になる.</p>
著者
Toru Kobayashi Rie Kurata Yumi Kai
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-025, (Released:2019-02-01)
被引用文献数
9

Despite increasing demand for sweet potato foliage, which is rich in functional components, efficient methods to maximize yield are still needed. In this study, cultivation tests for sweet potato (line Kyukei05303-3) were conducted over three consecutive years at a greenhouse to characterize seasonal changes in the foliage yield (leaves and stem-petioles), as well as the polyphenol content. The sweet potato foliage was harvested from May to November every week, and the average leaf yield was 855.3 g·m−2·year−1 on a dry weight (DW) basis. The yield and polyphenol content of the leaves were negatively correlated. The yield increased from spring to summer but decreased after mid-August. In contrast, the polyphenol content was highest in May, lower during the summer (June to August), and increased again after September. The average polyphenol content in the leaves was 6.9 g·100 g−1 DW and the total annual polyphenol yield was 59.0 g·m−2. The major component of polyphenols was caffeoylquinic acids. The seasonal changes in caffeoylquinic acids were highly correlated with the changes in total polyphenols. The polyphenol content was significantly correlated with air temperature, but not with sunshine duration, suggesting that air temperature is an important determinant of the polyphenol content during cultivation. These results provide a basis for the rapid cultivation of sweet potato for foliage production.
著者
Deping Hua Jinyu Fu Li Liu Xuhui Yang Qiaoling Zhang Meiting Xie
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-004, (Released:2019-01-19)
被引用文献数
9

Bitterness, caused by cucurbitacins, is present in some melon fruit. Although bitter compound biosynthesis and regulation in Cucurbitaceae plants have been reported, the dynamic changes in bitterness during fruit development are unknown. Bitterness severity was measured for 19 inbred melon lines, including 14 lines of Cucumis melo var. chinensis, two var. inodorus and three var. conomon, using a panel tasting method. The data showed that bitterness severity was different in several lines of var. chinensis during fruit growth and maturation. Nb46 and Nb320, two elite parental lines of var. chinensis used in melon breeding, were used as experimental materials. Bitterness was severe at stage I, but moderate and disappeared at stage II and III in the fruit of Nb46. There was non-bitterness in the fruit of Nb320 throughout the development period. Furthermore, the cucurbitacin B (CuB) content gradually decreased in Nb46, while in Nb320, the CuB content changed little and remained at a quite low level during fruit development. Different expression patterns of the genes involved in CuB biosynthesis and regulation were found between Nb46 and Nb320. The expression levels of these genes were significantly higher in Nb46 than Nb320 in the early developmental stages, and this correlated with a higher concentration of CuB in Nb46 than Nb320. These results demonstrate that bitterness severity is different in var. chinensis during fruit developmental stages, and that the CuB biosynthesis-related genes are a critical factor in this process. We hope these findings will contribute to the breeding of non-bitter melon cultivars.
著者
Mamoru Sato Kaori Matsuoka Tsugiko Takase Natsuko I. Kobayashi Hidetoshi Kikunaga Daisuke Takata Keitaro Tanoi Tsutomu Ohtsuki Shinnosuke Kusaba Katsuhiko Yamaguchi
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-006, (Released:2019-01-18)
被引用文献数
8

We investigated the vertical 137Cs distribution in soil among five sod culture orchards with different soil textures over six years after 2011, when 137Cs fallout was released by the Fukushima Daiichi Nuclear Power Plant accident, to confirm the long-term 137Cs downward-migration into soil. At each orchard, soil cores were collected to a depth of 30 cm and subdivided into intervals of 3 to 9 cm. The 137Cs within the 3 cm of topsoil decreased from 84–94% during the first 7 months after deposition in 2011 to 41–75% in 2017. From 2012 onward, the vertical 137Cs profiles in the soils were explained by a two-component negative exponential model composed of a rapid and a slow component with a change of slope at a depth of 6 to 9 cm. It took 4 years after deposition to show a significant difference in the value of the average 137Cs migration distance (Md) among the orchards. The speed of 137Cs migration in the orchards during the 6 years after the accident year was 0.44 to 0.97 cm year−1 based on the Md. There was a significant positive correlation between Md and fine sand content in the 3 cm of topsoil between Md and the ratio of the total carbon content (TC) at a depth of 3 to 6 cm to that in the top 3 cm of soil. Furthermore, the percentage of exchangeable 137Cs (ex-137Cs) to 137Cs at 3 to 6 cm depth increased significantly in proportion to the ratio of TC at 3 to 6 cm depth to TC at 0 to 3 cm depth in soil collected in 2013. These findings indicate that one of the mobile forms of 137Cs was ex-137Cs combined with TC and that the fine sand content and TC influenced the 137Cs downward-migration in the 3 cm of topsoil in the orchard in which organic matter accumulated by sod culture.
著者
Koji Numaguchi Shogo Ishio Yuto Kitamura Kentaro Nakamura Ryo Ishikawa Takashige Ishii
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-013, (Released:2019-01-18)
被引用文献数
7

Japanese apricot (Prunus mume Sieb. et Zucc.) is one of the major fruit tree crops in Japan. However, a paucity of molecular tools has limited studies on the species’ genetic diversity and clone identification. Therefore, we newly designed 201 microsatellite markers using the P. mume reference genome and selected 20 highly polymorphic markers. The markers showed higher polymorphism detectability than those previously developed using peach and apricot genomes. They were used successfully for fingerprinting most of the Prunus cultivars examined (124 P. mume accessions and one accession each of P. armeniaca, P. salicina, P. persica, and P. dulcis), and the resulting genotype data were used to examine the genetic differentiation of six Japanese apricot cultivar groups, including those producing normal fruit, small-fruit, and ornamental flowers, as well as Taiwanese cultivars, putative hybrids of P. armeniaca and P. mume, and putative hybrids of P. salicina and P. mume. Phylogenetic cluster analysis showed three clades with high support values; one clade comprised the putative P. armeniaca × P. mume hybrids, and the two others included Taiwanese and ornamental cultivars. The rest of the accessions were grouped into two wide clusters, but not clearly divided into the respective cultivar groups. These complex relationships were supported by the principal coordinate and STRUCTURE analyses. Since Japanese apricot is thought to have originated in China, many factors such as human preference, geographical separation, introgression, and local breeding, may have been involved to form the present complex genetic structure in Japanese apricot.
著者
Hikaru Matsumoto Yoshihiko Adachi Yoshinori Ikoma Masaya Kato
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-047, (Released:2019-01-09)
被引用文献数
8

In satsuma mandarin fruit (Citrus unshiu Marc.), β-cryptoxanthin is a major carotenoid and an important quality component in the juice sacs. The stage of maturity and storage conditions of satsuma mandarin fruit shipped to markets varies. However, the effects of maturation stage, storage temperature and duration on changes in β-cryptoxanthin content have not been fully studied. In the present study, fruits were harvested at different maturation stages, and changes in β-cryptoxanthin content in the juice sacs were investigated during storage at temperatures from 5 to 20°C. At 20°C, in fruit harvested while β-cryptoxanthin is still being accumulated on the tree, the content continued to increase following 15 days of storage. However, in the fruit without β-cryptoxanthin accumulation on the tree, the content did not increase. At 10°C, in the fruit accumulating β-cryptoxanthin on the tree, the content continued to increase after 14 days’ storage, whereas in the fruit without β-cryptoxanthin accumulation, the content did not increase after 14 days’ storage but increased after 30 days’ storage. At 8°C, the increase in content was also observed in the fruit when stored for 80 days. In contrast, at 5°C, the content did not change notably at any maturation stage regardless of the experimental period. The changes in the carotenoid content and gene expression suggest that carotenoid accumulation during on-tree maturation continues after harvest at 20°C, but not at 5°C. The present results suggest that β-cryptoxanthin content will not decrease at a range from 5 to 20°C irrespective of the maturation stage. Moreover, at 8°C and above, the β-cryptoxanthin content will gradually increase, and the rate will be more rapid in fruit harvested when carotenoid accumulation is in progress on the tree.
著者
佐藤 守 阿部 和博 菊永 英寿 高田 大輔 田野井 慶太朗 大槻 勤 村松 康行
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
vol.84, no.4, pp.295-304, 2015
被引用文献数
18

モモ[<i>Prunus persica</i>(L.)Batsch]とカキ(<i>Diospyros kaki</i> Thunb.)を供試し,福島第一原子力発電所事故の放射性降下物により休眠期汚染された落葉果樹に対する高圧洗浄機を用いた樹皮洗浄による放射性セシウムの除染効果を検証した.夏季洗浄処理として 18 年生モモ'あかつき'を供試し,2011 年 7 月 5 日と 27 日の 2 回にわたり,樹皮洗浄処理を実施した.休眠期洗浄処理として 2011 年 12 月 21 日に 30 年生カキ'蜂屋',2012 年 1 月 24 日に 7 年生モモ'川中島白桃'を供試し,樹皮洗浄処理を加えた.高圧洗浄処理によりカキではほぼ全ての粗皮がはく離したが,モモの表皮はほとんどはく離しなかった.2011 年夏季に洗浄処理されたモモ'あかつき'の果実中 <sup>137</sup>Cs 濃度は洗浄による有意差は認められなかった.2011 年から 2012 年の冬季に洗浄処理されたモモ'川中島白桃'の葉および果実中 <sup>137</sup>Cs 濃度は洗浄により有意に減少した.同様にカキ'蜂屋'でも洗浄処理翌年の葉および果実中 <sup>137</sup>Cs 濃度は洗浄により有意に減少した.これらの対照的な結果と矛盾しない現象として,汚染された樹皮洗浄液による二次汚染および樹皮からの追加的汚染の可能性について考察を加えた.
著者
Yuka Suehiro Keisuke Mochida Mitsuru Tsuma Yuji Yasuda Hiroyuki Itamura Tomoya Esumi
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-046, (Released:2018-12-29)
被引用文献数
10

Phytohormones play major roles in the berry maturation process. Gibberellic acid (GA) and cytokinin (CK) are phytohormones used in seedless table grape production. Several studies have been conducted on the effects of GA and CK application on berry development. However, the detailed mechanisms underlying their physiological effects on berry maturation after the veraison stage have not been clarified. Skin browning during maturation is a major commercial problem in yellow-green skinned grape cultivars including ‘Shine Muscat’, and expanding our knowledge of these mechanisms is a necessary step towards addressing this problem. In this study, we investigated the effects of GA and CK treatments from the veraison stage to the subsequent developmental stages of this grape berry. Both treatments resulted in enlarged berries and the suppression of increases in sugar content. Chlorophyll in the berry skin was less decomposed after GA/CK treatment, and the occurrence of skin browning in the maturation stage was reduced, as expression of the VvPP2Cs gene decreased. GA/CK treatment at the veraison stage (45–50 DAFB) reduced the expression levels of phytohormone-related genes, particularly those of VvGID1 and VvCHKs, which are involved in GA and CK signaling, respectively. These similar changes in gene expression patterns suggest phytohormonal crosstalk and a common expressional regulatory mechanism. VvACO2 and VvYUC1 expressions were significantly increased in skin browning samples, regardless of treatment, indicating involvement of the ethylene and auxin biosynthesis pathways in skin browning. Therefore, GA/CK treatment at the veraison stage may broadly affect phytohormone biosynthesis and signaling pathways in subsequent developmental stages, although the effect size greatly differs depending on the experimental conditions, including year and plant.