著者

Akiko Matsunaga 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.QH-024, (Released:2023-05-31)

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Garland chrysanthemum is conventionally ratooned and harvested by selective hand picking. This manually intensive mode of harvesting may be improved by adopting mechanized harvesting practices. In view of incorporating machine harvesting into garland chrysanthemum crops, this study evaluated the effects of plant and cutting height on ratoon crop regrowth. Garland chrysanthemums were horizontally harvested using six combinations of three plant height levels at harvest (20 cm, 30 cm, and 40 cm) and three cutting height levels (5 cm, 10 cm, and 15 cm) over three repeated harvests. Plant height at harvest as well as the cutting height affected the total ratooning yield and regrowth process. If plant heights at harvest were low (20 cm) or cutting height relative to plant height at harvest was excessively high, yields decreased. Higher plant heights at harvest and lower cutting heights resulted in longer regrowth periods. Evaluation of branch structures revealed that low cutting heights decreased the number of branches and nodes remaining for regrowth. If the plant height at harvest was low (20 cm), node numbers tended to decrease. Excessively high cutting heights relative to plant height at harvest potentially results in the harvest of immature leaves and stems. We determined that harvesting at 30 cm plant height with 10 cm cutting height was suitable for ratooning, and resulted in high yields. This combination resulted in a sufficient number of first lateral branches and nodes on the plants, thus enabled the harvest of fully grown leaves.

著者

Shota Niwayama Hirokazu Higuchi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.OKD-169, (Released:2018-10-26)

被引用文献数

7

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The suitable soil pH for passion fruit growth has been well studied; however, the optimal soil pH for producing high-quality fruit has not been determined. In this study, the effects of soil acidity on fruit quality were determined. One-year-old passion fruit plants were grown in pots filled with soil adjusted to four pH levels (pH 3.5, 4.5, 5.5, and 6.5). The numbers of flowers and fruits were counted, and the external appearance and juice quality of the harvested fruits was evaluated. Vegetative growth, physiological responses, and leaf mineral contents were also measured. At pH 4.5 and 5.5, fruit were heavier and larger, with a better peel color than the fruit at pH 3.5 and 6.5. As indicators of taste, the titratable acid content was lower and total soluble solid content was higher at pH 4.5 and 5.5, indicating preferable palatability. The sugar/acid ratio was highest at pH 4.5. The numbers of flowers and fruits, vegetative growth, and photosynthetic rate were also higher at pH 4.5 and 5.5. Conversely, soil with a near-neutral pH of 6.5 yielded fruit with a pale peel color, severe peel wrinkles, and a low sugar/acid ratio. Vegetative growth was inhibited, and the photosynthetic rate and leaf water potential were lowest at pH 6.5. The leaf/fruit ratio was lower at pH 6.5. A shortage of photosynthate may have reduced fruit quality. Leaf nitrogen, manganese, and zinc contents, as well as the chlorophyll content (SPAD index), were lowest at pH 6.5. Deficiencies in these minerals may have led to a low photosynthetic rate and SPAD index under the higher pH condition. With excessive acidic soil (pH 3.5), vegetative growth, photosynthetic rate, and the number of flowers were as high as those at pH 4.5, although the fruit-set percentage and fruit quality were lower. Thus, strongly acidic soil around pH 4.5 is recommended for producing high-quality passion fruit.

著者

Haruka Seto Serina Sasaki Yuko Mitobe Toru Ota Fumi Tatsuzawa

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-032, (Released:2023-05-26)

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The flower colors and flavonoids of 16 cultivars of Verbena hybrida Groenl. & Rumpler (Verbenaceae) were examined to evaluate the relationship between flower color and flavonoid components. Fifteen anthocyanins {3-O-glucoside, 3,5-di-O-glucoside, 3-O-[6-O-(acetyl)-glucoside], 3-O-[6-O-(malonyl)-glucoside], and 3,5-di-O-[6-O-(acetyl)-glucoside] of delphinidins, cyanidins, and pelargonidins}, seven flavones {7-O-(glucuronide) of apigenin, luteolin, tricetin, and 4'-O-methyl-luteolin, 7-O-[2-O-(glucuronosyl)-glucuronide]-4'-O-(glucuronide) of apigenin, and 7-O-[2-O-(glucuronosyl)-glucuronide] of apigenin and luteolin}, two flavonols {3-O-glucoside and 3-O-[6-O-(acetyl)-glucoside] of kaempferols}, and chlorogenic acid were isolated from the flowers of these cultivars. Their structures were identified using co-HPLC, nuclear magnetic resonance, and mass spectrometry. For the Red to Purple-Violet cultivars, the corresponding color chart names were responsible for the major anthocyanidin types, and the hue values (b*/a*) of these flower colors reflected the anthocyanins concentration. Based on the relationship between the distribution of flavones, flavonols, and chlorogenic acid among cultivars and flower color, we conclude that flavonoids other than anthocyanins and chlorogenic acid make little contribution to flower color. The yellowish red color is thought to be affected by carotenoids.

著者

Rie Kurata Toru Kobayashi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-044, (Released:2023-05-26)

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Purple sweet potatoes are rich in the purple pigment anthocyanin. In recent years, it has been reported that the anthocyanin content of the same variety varies depending on the place of production. Therefore, to investigate the effect of soil temperature on the anthocyanin content of sweet potato tuberous roots, two types of covering materials, black and white mulch films, were used in the same field. The vines were planted in May, June and July; the cultivation period was set to 120–180 days and tuberous roots were harvested in September, October and November. The average soil temperature ranged from 22.9 to 26.5°C, with the white mulch having lower soil temperatures than the black mulch. The tuberous root yield increased with longer cultivation periods; the tuberous root yield in the May–November plot with a 180-day cultivation period was about twice that of the June–October and July–November plots with a 120-day cultivation period. The anthocyanin content of the tuberous root was negatively correlated with the average soil temperature; the test plots harvested in November had a higher anthocyanin content than the other test plots. In particular, the anthocyanin content of sweet potato cultivated in white mulch in July–November was about twice that cultivated in May–September. Although the factors that increase the tuberous root yield (prolonged cultivation period) are different from those that increase the anthocyanin content (lower temperature range), the tuberous root yield showed a larger effect on the total anthocyanin yield. Since the cultivation period needs to be prolonged to increase tuberous root yield, it would consequently increase the anthocyanin yield. The quality of the harvest was better under lower soil temperature as it led to an increase in the anthocyanin yield. Therefore, it was suggested that anthocyanin yields could be maximized by extending the growing season and harvesting at lower soil temperatures.

著者

Toshihiko Sugiura Makoto Takeuchi Takuya Kobayashi Yuta Omine Itaru Yonaha Shohei Konno Moriyuki Shoda

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-055, (Released:2023-05-26)

被引用文献数

1

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Pineapples (Ananas comosus (L.) Merr.) are harvested throughout the year, with acid and soluble solid contents varying with season. However, there is a lack of knowledge about the relationship between the acid and soluble solid content and climatic factors. To investigate these relationships, we analyzed the acid and soluble solid content records of a large number of fruit harvested over 15 years from three production areas in Japan. Over the warm period (June to September) pineapple acid content was low, while over the cool period (December to April) it was high, regardless of the cultivar. Soluble solid contents were highest in June and lowest between September and March. Acid content at harvest inversely correlated with the temperature immediately before harvest, and the relationship modelled linearly with the mean temperature over the 10 or 20 days before harvest as a variable. The acid content of ‘N67-10’ is highly dependent on temperature, while that of ‘Okinou P17’ is stable regardless of temperature. The soluble solid content was affected by temperature over longer periods than the acid content and was modelled using a quadratic equation with the mean temperature over the 70–120 days before harvest as a variable. The approximate curve of soluble solid content peaked around 23°C. The majority of ‘Okinou P17’ fruit yielded a soluble solid content of > 15 °Brix over a wide temperature range (≥ 19°C), while the temperature at which most ‘N67-10’ fruit had soluble solid of > 15 °Brix was limited to a narrow range (22–23°C). Although the coefficients of both model equations were significant for all cultivars, the R2 of soluble solid content was smaller than that of acid content. These results contribute to understanding the relationship between acid and soluble solid content and temperature.

著者

Slamet Susanto Abdullah Bin Arif Siti Mariana Widayanti Deden Derajat Matra

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-053, (Released:2023-04-25)

被引用文献数

1

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Abiu is a tropical fruit with many beneficial bioactive compounds. However, its economic value is limited by a short shelf life and rapid browning. This study evaluated the effect of ascorbic acid on extending abiu fruit shelf life during storage. The fruit was soaked in ascorbic acid solutions of 0 mM (control), 5 mM (AA5), and 10 mM (AA10) for 10 minutes, air-dried, then stored in an ambient room (28 ± 1°C and 80 ± 5% RH) for 12 days. The results indicated that the 10 mM exogenous ascorbic acid treatment increased abiu fruit shelf life up to 12 days, nine days longer than the control. Abiu fruit, after the AA10 treatment, underwent a 1.4-fold lower weight loss than the control. In addition, on day 12 of storage, the browning of fruit with the AA10 treatment were 8 and 11% on the peel and pulp, respectively. The climacteric peak of abiu fruit in the AA10 treatment occurred on day 8 of storage, three days later than the control. The AA10 treatment also maintained vitamin C content and fruit firmness. Thus, the AA10 treatment effectively extended shelf life and maintained abiu fruit quality.

著者

Kyutaro Kishimoto Yusuke Watanabe Seiji Ikegawa

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-025, (Released:2023-04-12)

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Tulip (Tulipa gesneriana L.) cultivars exhibit diverse floral scents, the emissions of which are generally influenced by temperature. To fully benefit from these scents and add value to cut tulips, it is necessary to evaluate the scent emission response to temperature. This study investigated the daily emission changes of 82 volatiles, including the main scent compounds, at different temperatures (13, 18, and 23°C), in the cut tulips from eight tulip cultivars with different scents. At 23 and 18°C, the total scent emissions of each cultivar increased with flower opening and subsequently decreased with visible senescence. Floral senescence progressed more rapidly at 23°C, and the decrease in total scent emission occurred most rapidly at 23°C. Scent emissions at 18°C tended to be lower than at 23°C. The vase life of the cut tulips was most prolonged at 13°C owing to the slow senescence; however, scent emissions remained low after the flower opening. These results indicate that improving both tulip scent emission and vase life under constant temperature conditions is difficult. It was observed that scent composition changed before and after flower opening, and with floral senescence. In contrast, temperature had little effect on scent composition. Cut tulips stored at a low temperature (10 or 15°C) over four and a half days and then transferred to room temperature (20°C) had a longer vase life than tulips maintained at room temperature, due to delayed senescence. In addition, scent emissions were low at low temperatures, but increased rapidly upon transfer to room temperature. Therefore, storage of cut tulips at low temperatures may lead to increased scent emissions upon transfer to room temperature. These findings imply that low-temperature storage of cut tulips before sale contributes to both vase life and a rich scent after sale. The results reported here demonstrate the improvement of cut tulip scent emissions by appropriate temperature management.

著者

Takashi Onozaki Takuo Fujimoto

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-049, (Released:2023-04-12)

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Genetic improvement of flower vase life is an important breeding target for ornamental plants. As the vase life of cut dahlia (Dahlia variabilis) flowers is very short, we initiated a conventional crossbreeding research program in 2014 to improve it. We evaluated the vase life of dahlia seedlings during summer (from July to early September) to develop dahlias that grow and bloom under high temperatures and have excellent vase life for Japanese summer conditions. Crossing and selection over five generations greatly improved vase life. The mean vase life increased from 4.4 days in the 1st generation, derived from 22 parental cultivars, to 8.0 days in the 5th generation, a net increase of 3.6 days. Mean vase life increased significantly by 1.6 days from the 4th to the 5th generation, indicating continued improvement. The mean vase life of the 12 lines selected from the 3rd and 4th generations ranged between 6.0 and 15.9 days in distilled water and from 7.8 to 14.6 days in GLA solution (10 g·L−1 glucose, 0.5 mL·L−1 CMIT/MIT [isothiazolinone derivatives], and 50 mg·L−1 aluminum sulfate). Vase life was further extended by 0.5 to 4.0 days using 6-benzylaminopurine (BA) sprays compared to GLA alone. In particular, the 4th-generation line 003-15 vase life was 13.8 to 15.9 days (2.5× that of ‘Kamakura’, a leading white dahlia cultivar in Japan) in distilled water, 12.0 to 14.6 days (1.8× to 2.2×) in GLA, and 13.9 to 15.3 days (1.7× to 1.9×) in GLA+BA in winter and spring. Cut flowers of line 003-15 harvested under high temperatures in July–August and at 28°C with GLA treatment also had long vase life. The pedigree of line 003-15 suggests that genes related to long vase life derived from ‘Micchan’ (with a long vase life) may have accumulated or duplicated in line 003-15. Finally, four selected lines, including 003-15, had high ethylene sensitivity, as 10 μL·L−1 ethylene treatment caused petal abscission in 2.0 to 2.8 days.

著者

Akane Shibasaki Tomohito Shimada Satoru Kondo Hitoshi Ohara Katsuya Ohkawa

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-030, (Released:2023-03-11)

被引用文献数

2

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Artificial pollination is essential in pears (Pyrus spp.) for stable fruit set and the production of high-quality fruit. Low temperatures in the early spring before bud flowering can damage pear pollen and pose a special risk to pollen production for artificial pollination. In this study, we sought to identify, in pears, the flower bud stage most susceptible to low-temperature pollen damage, observe anther development abnormalities, compare pollen sensitivities among seven pear cultivars, and evaluate the pollen cold injury inhibition efficacy of a coffee extract treatment for flower buds. The most cold-sensitive flower bud stage for the Japanese pear ‘Kosui’ pollen was the scale-separation stage, with pollen in that stage ranging from the pollen mother cell to the tetrad stage. In the ‘Kosui’ flower bud treated at −3°C over 10 h, the typical cold-induced anther development abnormalities were tapetum hypertrophy, cell debris, and anther locule shrinkage. Flower buds at the scale-separation stage of seven pear cultivars were treated with low temperatures in a model based on daily temperature changes during the winter season in Saitama, Japan, to reach daily minimum temperatures of 0, −1, −2, −3, −4, −5, and −6°C. The pollen germination rates of ‘Hosui’ were unaffected by low-temperature treatments between 0 and −6°C. Overall ‘Hosui’ showed the least reduction in pollen germination rate than the other cultivars evaluated. Our results strongly suggest that ‘Hosui’ is the most tolerant to low temperatures among the tested cultivars. In the laboratory environment, the application of a coffee extract before cold treatment delayed flower bud freezing and preserved pollen germination. These results are helpful in selecting varieties and treatments for the prevention of cold injury in pear pollen production.

著者

Ladawan Lerslerwong Chompoonut Buapuean Adirek Rugkong Kanokporn Bunya-Atichart

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-033, (Released:2023-03-10)

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Limes (Citrus aurantifolia Swingle) have a short postharvest life. Therefore, effective treatments increasing storage life to lengthen the time that produce remains fresh is desirable. This study evaluated the effects of postharvest treatments of 1-methylcyclopropene (1-MCP), gibberellic acid (GA3), and Aloe vera on lime storage life and fruit quality. The optimum individual treatments of 50% Aloe vera coating, 300 mL·L−1 GA3, and 750 nL·L−1 1-MCP were identified as most effective in extending lime postharvest life. Under ambient conditions (26.4 ± 1.0°C, 64.4 ± 7.4% RH), 1-MCP fumigation was the best treatment, increasing lime postharvest life to 28.2 days. The 1-MCP-treated fruit had a higher juice content than the control fruit. Also, soluble solid contents and titratable acidity were not significantly different, while ascorbic acid was lower than the control. Under cold room conditions (10.0 ± 0.3°C, 68.9 ± 12.4% RH), 1-MCP fumigation followed by Aloe vera coating was the best treatment, increasing lime storage life by 38.7 days. The longer storage time did reduce juice content in treated limes compared to untreated fruit. However, the treatment did not affect the soluble solid contents, titratable acidity, or ascorbic acid level. In conclusion, for optimum postharvest life in limes stored under ambient conditions, fumigation with 1-MCP is best. While for limes stored in cold rooms, a cotreatment of 1-MCP fumigation followed by Aloe vera coating maximizes postharvest life.

著者

Naomi Oyama-Okubo Yuki Mikanagi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-050, (Released:2023-02-18)

被引用文献数

2

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Rosa foetida Herrm. is an important wild rose that contributed to the birth of modern yellow cultivars. It is also well known for the unpleasant odor, not prevalent in other roses, emanating from its petals. We analyzed the floral scent of R. foetida and its sport cultivars, R. foetida var. bicolor (Jacq.) Willm. and R. foetida f. persiana (Lem.) Rehd., to identify the causative compounds for their offensive odor. Fatty acid derivatives 2,4-decadienal (2,4-DA), 2,4-decadienol (2,4-DO), and (Z)-jasmone were detected by gas chromatography-mass spectrometry along with several terpenoids, phenylpropanoids, and hydrocarbons. Among them, 2,4-DA and 2,4-DO were identified as the causative compounds of the offensive odor. This is the first detection of these fatty acid derivatives in the scent of rose flowers. We also analyzed the floral scent of eight descendant cultivars of R. foetida: ‘Agnes’, ‘Harison’s Yellow’, ‘Rhodophile Gravereaux’, ‘Schloss Seusslitz’, ‘Soleil d’Or’, ‘Star of Persia’, ‘The Queen Alexandra Rose’, and ‘Williams’ Double Yellow’. 2,4-DA and 2,4-DO were only detected in the smell of ‘Star of Persia’. No other descendant was found to emit these fatty acids. This is the first analysis of an unpleasant odor in roses.

著者

Ayumu Kono Ayumu Kawabata Akira Yamazaki Yuma Ohkubo Adriano Sofo Munetaka Hosokawa

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-037, (Released:2022-11-30)

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We investigated the effect of ultraviolet-B (UV-B) irradiation on the development of black spot disease caused by Diplocarpon rosae Wolf., which is a major problematic disease in rose (Rosa × hybrida) production. The growth of D. rosae colonies was suppressed on potato dextrose agar (PDA) medium under UV-B irradiation (peak wavelength: 310 nm; full width at half maximum: 30 nm) at an intensity of 15 μW·cm−2 with 1 h daily treatment. In addition, black spot conidia were inoculated to the rose ‘Danjiri Bayashi’ leaves and the effective growth suppression of black spot symptoms was observed on the leaves under UV-B irradiation. Next, various rose cultivars were planted in two greenhouses: one for supplemental UV-B irradiation treatment and one as a control without the treatment. In the UV-B irradiation greenhouse, the roses were irradiated at an intensity of 3–5 μW·cm−2 every day from 23:00–23:30 and 0:00–0:30 (total: 1 h). No chemical pesticides other than a starch agent for aphid control were used throughout the experiment. With the exception of the data for ‘Papa Meilland’ in 2019, UV-B irradiation significantly reduced the number of leaves infected with black spot disease. In September 2019, the non-UV-B irradiated ‘Danjiri Bayashi’ and ‘Papa Meilland’ had severe black spot symptoms on over 20 leaves. The number of plants with black spot symptoms increased in July 2020 compared to 2019. On the other hand, in UV-B irradiated plants, fewer black spot symptoms were observed than in non-UV-B irradiated plants. Although some visible damage was observed in the UV-B irradiated plants, the chlorophyll and carotenoid contents in the leaves decreased, indicating that UV-B irradiation had a certain negative effect on the photosynthetic apparatus. Over a five-month period, the cumulative number of flowers in the UV-B irradiation greenhouse did not decrease, and actually increased, depending on the cultivar, compared to the control treatments. Our results suggest that supplemental UV-B irradiation is effective at suppressing black spot disease in roses and can contribute to the production of pesticide-free edible rose production.

著者

Mei Gao-Takai Zen Lin Yuta Sugiyama Takane Katayama Ai Shinmura Hikaru Naito Ayako Katayama-Ikegami

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-371, (Released:2022-07-05)

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This study investigated anthocyanin accumulation, sugar contents, and endogenous hormone contents in the berry skin, as well as the expression of genes related to anthocyanin and abscisic acid (ABA) synthesis and metabolism, using grafted ‘Ruby Roman’ berries on the rootstocks of ‘Kober 5BB’ [5BB(2x), a semidwarf rootstock], ‘Hybrid Franc’ [HF(2x), a vigorous rootstock], and their colchicine-induced autotetraploids [5BB(4x) and HF(4x)]. Rootstock had significant effects on the total content, but not on the composition, of anthocyanins. The berries on 5BB(4x) rootstock, where the grapevine showed less vegetative growth, had higher anthocyanin content during the ripening process, and also had higher sugar and ABA contents around véraison. ABA, indole acetic acid (IAA), and cytokinins showed synchronous changes during berry development: they had the lowest levels at pre-véraison, and their metabolic pathways were accelerated after véraison. Furthermore, they all tended to be higher on 5BB(4x) than on the other rootstocks. Since the expression levels of most of the ABA biosynthesis-related genes did not show a corresponding increase with the contents of ABA and ABA-glucosyl ester (ABA-GE), it is considered that the increase in ABA content after véraison may be mainly due to the decrease in catabolism and/or exogenous import from other organs. This study provides an overview showing the dynamic changes and relationship of three phytohormones during the ripening of grape berries grafted on different rootstocks, and explores the mechanisms regulating ripening.

著者

Yutaro Osako Hisayo Yamane Ryunhee Kim Hisashi Miyagawa Ryutaro Tao

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-352, (Released:2022-05-19)

被引用文献数

1

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Seed size affects the edible portion rate of lychee fruit and is therefore an important trait for fruit quality in lychee (Litchi chinensis). Lychee fruits can be classified into four categories in terms of seed properties: normal, small, aborted seed and seedless. ‘Salathiel’ is known to bear a relatively high rate of aborted-seeded (pseudo-parthenocarpy, stenospermocarpy) and seedless (parthenocarpy) fruit regardless of environmental and cultivation conditions. In other horticultural fruit crops, such as tomato, auxin metabolism and signaling is critical for parthenocarpy, although auxin metabolism has not been characterized in relation to (pseudo) parthenocarpy in lychee. The purpose of this study was to characterize the physiological and morphological properties of maternal reproductive organs in ‘Salathiel’ female flowers, with a specific focus on the associated auxin metabolism. Microscopic observations of the internal structures of the ‘Salathiel’ embryo revealed that ‘Salathiel’ reproductive organ differentiation is similar to that of normal-seeded cultivars. However, the obturator was significantly smaller in ‘Salathiel’ than in other normal-seeded cultivars, suggesting that specific developmental characteristics may exist in the maternal reproductive organs of ‘Salathiel’. Our investigation of indole acetic acid (IAA) contents revealed that IAA levels were significantly higher in ‘Salathiel’ than in other cultivars. Moreover, the IAA metabolite contents also differed significantly between ‘Salathiel’ and the normal-seeded and small-seeded cultivars. Specifically, N-3-hydroxy-2-oxindole-3-acetyl glutamic acid contents were significantly higher in ‘Salathiel’ than in ‘Yu Her Pau’ and ‘Hei Ye’. 3-hydroxy-2-oxindole-3-acetic acid was lower in ‘Yu Her Pau’ and ‘Salathiel’ than in ‘Hei Ye’, while indole-acetylaspartic acid was significantly lower in ‘Salathiel’ compared to ‘Hei Ye’. Expression analyses of the genes related to auxin biosynthesis, catabolism, transport, and signaling indicated that the IAA influx-related and efflux-related gene expression levels were respectively higher and lower in ‘Salathiel’ than in the other cultivars, which is consistent with the increased IAA accumulation in the ‘Salathiel’ ovary. The possible involvement of auxin metabolism in the aborted-seeded and seedless fruit production in ‘Salathiel’ is discussed herein.

著者

Masumi Yamagishi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-373, (Released:2022-05-25)

被引用文献数

2

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The lily MYB12 gene, a positive regulator of anthocyanin biosynthesis, is targeted by microRNA828 (miR828). In bicolor tepals of Asiatic hybrid lilies with white lower halves and pigmented upper halves, accumulation levels of miR828 are higher in the lower halves than in the upper halves, and action of MYB12 is suppressed in the lower halves, resulting in bicolor tepal development. This is a newly identified mechanism of color pattern development in flowers. However, which wild species has donated the miR828-mediated bicolor tepal traits to these hybrid lilies is uncertain, and whether miR828-dependent pattern development occurs in species other than Lilium and is responsible for other types of color patterns is unknown. In this study, miR828 accumulation levels were compared between anthocyanin pigmented and unpigmented regions of flowers in lilies and other species. Lilium dauricum is among the parental wild species of Asiatic hybrid lilies. Lilium dauricum showed bicolor tepals, in which anthocyanins highly accumulated in the upper halves, and miR828 accumulation was more than 10 times higher in the lower halves than in the upper halves. Thus, the profile of miR828 accumulation was similar to that found in bicolor cultivars of Asiatic hybrid lilies. It is possible that the miR828-mediated bicolor tepal trait in Asiatic hybrid lilies is derived from L. dauricum. In L. cernuum var. album and an Oriental hybrid lily ‘Dizzy’, the suppression of MYB12 expression causes unpigmented tepals or tepal regions, but the unpigmented regions are spatially different from those in bicolor tepals of Asiatic hybrid lilies. MiR828 accumulation levels were similar between white and pink flowers of L. cernuum, and rather higher in pigmented regions than white regions of ‘Dizzy’ tepals, suggesting little involvement of miR828 in MYB12 expression suppression. MiR828 accumulation levels were evaluated in bicolor flowers of cherry sage, tulip, and Alstroemeria, but differences in miR828 accumulation were not detected between red and white petal/tepal regions, indicating that the mechanisms by which the bicolor flowers developed in these species are likely different from that occurring in Asiatic hybrid lilies and L. dauricum. Thus, the miR828/R2R3-MYB module is likely responsible for color only in lily flowers and only for the color pattern that consists of lower un-pigmented and upper pigmented regions.

著者

Haruna Yada Chihiro Matsumoto Xiaonan Xie Kazuhisa Kato Hiroki Ikeda

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-356, (Released:2022-03-16)

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Fruit mass is an important factor for determining the yield of tomatoes (Solanum lycopersicum), with higher mass being an important objective. Most fruit traits, including fruit mass, are quantitative, and numerous quantitative trait loci (QTL) control these traits. Previous studies investigating tomato introgression lines (ILs) revealed several QTLs for fruit yield, and suggested that IL12-1 is a potential line to increase fruit mass. Our aim was to facilitate genetic studies of the diverse characteristics of wild relatives of tomato. Therefore, tomato ILs from a cross between Solanum pennellii and the cultivar S. lycopersicum ‘M82’ were used. ILs that carry a S. pennellii chromosome segment on chromosome 12 of ‘M82’ were evaluated further for fruit mass expansion and regulation. IL12-1-1, a subline of IL12-1, was found to produce large ripening fruits compared with ‘M82’, a phenotype that resulted in increased pericarp thicknesses. To investigate the physiological mechanisms contributing to the increased fruit mass of IL12-1-1, the cell counts of fruit pericarp tissues during fruit development were evaluated. Cell numbers of IL12-1-1 fruit pericarp at 20 days after flowering were higher than those of ‘M82’, a difference that most likely occurred during the cell division phase. In addition, the levels of the phytohormones auxin and cytokinin, which are known to be related to cell division of the fruit tissue, were higher in IL12-1-1 compared with ‘M82’. Therefore, differences in these phytohormones between ‘M82’ and IL12-1-1 may be affected by the number of cells in the pericarp tissues. Expression analysis of Solyc12g005250 (SlKLP) and Solyc12g005310 (SlGH3-15), which are located in the IL12-1-1 region of the S. pennellii chromosome, showed significant differences between ‘M82’ and IL12-1-1 during the cell division phase; a better understanding of IL12-1-1 cellular and molecular features can contribute to the breeding and increased production of tomato crops.

著者

Sho Ohno Mizuki Yokota Haruka Yamada Fumi Tatsuzawa 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-305, (Released:2021-08-04)

被引用文献数

6

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Yellow color in dahlia flowers is conferred from chalcones, butein and isoliquiritigenin. The color intensity of yellow dahlia cultivars is diverse, but a detailed study on this has not yet been performed. In this study, we first identified structures of flavonoids by nuclear magnetic resonance imaging in ray florets of the red-white bicolor ‘Shukuhai’, which contains chalcones, flavones and anthocyanins. Four anthocyanins, four flavone derivatives, five isoliquiritigenin derivatives and five butein derivatives were identified. Among the identified compounds, butein 4'-malonylsophoroside is considered to be the final product for butein derivatives and the presence of chalcone 4'-glucosyltransferase, chalcone 4'-glucoside glucosyltransferase, and chalcone 4'-glucoside malonyltransferase for isoliquiritigenin and butein modification was predicted. Also, the biosynthetic pathway of butein and isoliquiritigenin derivatives in dahlia with butein 4'-malonylsophoroside as the final product was predicted from the identified compounds. Next, we used nine yellow cultivars and lines with different color intensities and analyzed the correlation between the b* value, an indicator of yellow color, and level of chalcones. There was no difference in the presence or absence of major peaks among the cultivars and lines. Peak area per fresh weight measured by HPLC was high in butein 4'-malonylglucoside, butein 4'-sophoroside and isoliquiritigenin 4'-malonylglucoside, suggesting these three compounds were accumulated abundantly. Among the identified chalcones, the highest correlation coefficient was detected between the b* value and butein 4'-malonylglucoside (r = 0.86), butein 4'-sophoroside (r = 0.82) or isoliquiritigenin 4'-malonylglucoside (r = 0.76). These results suggest that these three chalcones confer yellow color in dahlia ray florets. The findings in this study will contribute not only to efforts at breeding new yellow dahlia cultivars, but also to molecular breeding of yellow flowers in other species by introducing the butein biosynthetic pathway.

著者

Yasushi Kawasaki Yuki Yoneda

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-R004, (Released:2019-04-05)

被引用文献数

21

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Uniform temperature throughout a greenhouse is recommended, as the present climate control method and many other studies have shown that the temperature gradient decreases vertically and horizontally in a greenhouse. However, recent research revealed that roots, fruits, flowers, and shoot-tips are more sensitive to temperature changes than leaves and stems, indicating that uniform temperature control may not be necessary. In addition, energy-saving techniques that do not lead to yield loss are desirable to reduce energy costs and ensure sustainable greenhouse production. In this paper, we review current studies on local temperature control methods in greenhouse vegetable production, primarily focusing on the tomato, and compare them with novel climate-control techniques. Roots, fruits, shoot-tips and flowers are sensitive to temperature changes, showing negative symptoms under extreme temperature conditions. Therefore, the temperature of these plant organs should be controlled locally. Root zone temperature control enhances root growth and its associated physiological activities, promoting uptake of water and mineral nutrients. This subsequently leads to enhanced growth of shoots. Fruit temperature control may not be effective for tomato plants, but it promotes fruit growth and fruit sugar accumulation in melons and watermelons. Shoot-tip temperature control promotes the differentiation of leaf and flower buds. Flower temperature control enhances pollen viability and promotes fruit set. The combination of shoot-tip and flower heating enables low energy consumption compared with conventional heating, without loss of yield. Local temperature control techniques (except roots) have been studied in recent years; however, there is a distinct lack of research on the physiological mechanisms and practical approaches to develop a better local temperature control system. Thus, further studies are required on this area in the future.

著者

Yuya Mochizuki Tiejun Zhao Wataru Kanematsu Takashi Kawasaki Takeshi Saito Akio Ohyama Akimasa Nakano Tadahisa Higashide

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-055, (Released:2019-04-11)

被引用文献数

4

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To clarify the effect of ultrafine bubbles (UFBs) on the growth of tomato seedlings, we investigated elongation growth and dry matter production by analysing growth under different assimilation conditions and by modelling. The leaf area enlargement rate of plants grown with UFB nutrient solution increased and the specific leaf area (SLA) decreased at 18 days after sowing (DAS) relative to those grown without UFB solution. Thus, UFBs increased both leaf area and leaf thickness. UFB significantly increased the relative growth rate (RGR) and net assimilation rate (NAR) at 18 DAS, but there was no significant difference in SLA, RGR, and NAR between treatments at 25 DAS. These results were used to model plant growth with and without UFB treatment. In a second experiment, UFB treatment increased aboveground dry weight under a low-assimilation condition, but had no significant effect under a high-assimilation condition. Our model supported these results. It was also implied that UFB treatment affected leaf area expansion, but not dry matter production. Although the values predicted by the model were slightly lower than observed, it was possible to predict the effect of UFB treatment on plant growth with high accuracy.

著者

Hadiseh Haghi Vali Rabiei Ahmad Ershadi Farhang Razavi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-056, (Released:2019-04-13)

被引用文献数

6

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As a major growth limitation, low temperature-induced injuries may adversely affect grape production in many areas. Ten-year-old grapevines ‘Thompson Seedless’ were sprayed with calcium chloride (CaCl2) three times at 10-day intervals from 19th September to 8th October 2015 and again in 2016 in a commercial vineyard. Bud samples were collected in December 2015 and 2016, January 2015 and 2016 and February 2016 and 2017. The buds were exposed to freezing treatments: −12, −16, −20, −24, and −28°C for 3 hours, to assess their low temperature tolerance. Moreover, the relationships among freezing tolerance and changes in antioxidant enzyme activity, soluble carbohydrates, proline and total proteins were investigated. Irrespective of foliar spray treatments, the freezing tolerance of buds increased from December to January and decreased in February. Application of CaCl2 at a 1% concentration resulted in increased bud freezing tolerance compared to the control plants. Application of 1% CaCl2 considerably increased the concentrations of soluble carbohydrates and total proteins in buds, but had subtle and inconsistent effects on proline. Activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX) were increased in response to foliar application of CaCl2; however, inconsistent changes were found in the activities of catalase and peroxidase following CaCl2 application. The results showed that application of 1% CaCl2 increased freezing tolerance of grapevines predominantly via upregulating soluble carbohydrates and total proteins.