著者

Yuka Inada Naomi Oyama-Okubo 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.QH-066, (Released:2023-06-10)

---

Although a strong floral scent is typical of hybrid lilies, Asiatic hybrid lilies (Lilium spp.) have only a weak scent. Therefore, developing new cultivars with pleasant floral scents is an important objective in Asiatic hybrid lily breeding programs. Among the wild species contributing to Asiatic hybrid lily establishment, L. cernuum has a characteristic scent that the nose can perceive. We crossed Asiatic hybrid lily cultivars twice with L. cernuum to introduce floral scent traits into Asiatic hybrid lilies, and scent emission in the F1 plants and their progeny lines was evaluated instrumentally. Flowers of L. cernuum emitted benzenoids/phenylpropanoids (mainly 2-phenylethanol and benzaldehyde), monoterpenes (predominantly linalool and linalool oxides), and a fatty acid (iso-valeric acid). Lilium cernuum gave off unpleasant odors mainly because of iso-valeric acid emission. The F1 flowers also emitted these three chemical classes. Among the lines derived from the crosses between Asiatic hybrid lily cultivars and the F1 plant, lines that emitted all three chemical classes and lines that released one or two of the three chemical classes were segregated, and some lines emitted benzenoids/phenylpropanoids or terpenoids without emitting fatty acids. We successfully selected elite breeding lines that predominantly emitted pleasant scents. Therefore, this study demonstrated the introduction of pleasant scent production capability into Asiatic hybrid lilies using interspecific hybridization with L. cernuum.

著者

Kenji Nashima Makoto Takeuchi Chie Moromizato Yuta Omine Moriyuki Shoda Naoya Urasaki Kazuhiko Tarora Ayaka Irei Kenta Shirasawa Masahiko Yamada Miyuki Kunihisa Chikako Nishitani Toshiya Yamamoto

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.QH-063, (Released:2023-05-31)

---

The pineapple (Ananas comosus (L.) Merr.) is an economically important tropical fruit crop. In this study, we performed quantitative trait locus (QTL) analysis using 168 individuals of the F1 population of ‘Yugafu’ × ‘Yonekura’ for 15 traits: leaf color (L*, a*, b*), harvest day, crown number, slip number, stem shoot number, sucker number, fruit weight, fruit height, fruit diameter, fruit shell color, soluble solid content, acidity, and ascorbic acid content. The constructed single-nucleotide polymorphism (SNP)-based genetic linkage map consisted of a total genetic distance of 2,595 cM with 3,123 loci, including 22,330 SNPs across 25 chromosomes. QTL analysis detected 13 QTLs for 9 traits: leaf color a*, harvest day, fruit weight, fruit height, fruit diameter, fruit shell color, soluble solid content, acidity, and ascorbic acid content. The causative gene for each QTL was predicted with two genes identified as candidate genes. The AcCCD4 gene on Aco3.3C08 was the predicted causative gene for the shell color QTL, which negatively controls shell color by carotenoid degradation. The Myb domain protein-encoding gene on Aco3.3C02 was the predicted causative gene for shell color and leaf color a* QTL, which positively regulates anthocyanin accumulation. The QTL and gene information provided here contributes to future marker-assisted selection for fruit quality.

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)

---

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

---

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)

---

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)

---

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

---

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

---

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)

---

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)

---

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

---

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)

---

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

---

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

河崎 靖 松尾 哲 鈴木 克己 金山 喜則 金濱 耕基

出版者

THE JAPANESE SOCIETY FOR HORTICULTURAL SCIENCE

雑誌

Journal of the Japanese Society for Horticultural Science (ISSN:18823351)

巻号頁・発行日

vol.82, no.4, pp.322-327, 2013 (Released:2013-11-16)

参考文献数

25

被引用文献数

11 12

---

トマト施設生産において高温障害を緩和する低コストな冷却技術が求められている.本研究では根域冷却の生理学的・形態学的知見を得ることを目的に,養液栽培されたトマトの培養液を最適温度と考えられるおよそ 25°Cに冷却して 2 週間栽培し,生育,養分吸収,根の活性としての出液速度および根呼吸速度,根の IAA 濃度および根の内部形態について調査した.高気温条件下で根域を最適な温度に冷却することで,根の RGR が増加し,その後地上部の RGR も増加した.根の IAA 含量は根の RGR と高い正の相関が認められた.根域冷却により出液速度,根呼吸速度が増加し,同様に Ca および Mg 吸収が促進された.また,根先端付近の木部発達も認められた.以上のことから,高温期の根域冷却は,根の活性および IAA 濃度を増加させることで,根の生育および木部発達を介した養分吸収を促進し,遅れて地上部の生育を促進することが示唆された.

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)

---

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)

---

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

岩堀 修一 崎山 亮三 高橋 和彦

出版者

THE JAPANESE SOCIETY FOR HORTICULTURAL SCIENCE

雑誌

園芸学会雑誌 (ISSN:00137626)

巻号頁・発行日

vol.32, no.3, pp.197-204, 1963 (Released:2007-05-31)

参考文献数

9

被引用文献数

2 3

---

1. トマト福寿2号を用いて, 6段階の苗齢のそれぞれについて, 30(対照区), 35, 40, 45°Cの高温処理を1日3時間ずつ連続5日間行ない, その後の生育, 着果を調べた。2. 苗齢VI(本葉14~15枚)の45°C区を除いて生育障害はなかつた。3. 本葉5枚までの苗は高温処理で着果率は減少しなかつた。しかし, 本葉8, 11, 14~15枚の苗は高温により着果率, 収量ともに減少し, その程度は処理温度が高いほど, また苗齢が進んでいるものほど著しかつた。本葉8枚の苗は第1花房, 11枚の苗は第1, 2花房, 14~15枚の苗は第1~3花房までが障害をうけた。4. 発育のステージを異にする花蕾に対する高温の影響をみると, 開花15日前~開花9日後ごろの花蕾が高温の影響をうけ, とくに開花5日前ごろと開花1日後は着果率の減少がはなはだしかつた。5. 開花中または開花後高温をうけた花からは小粒果が出現した。それ以外の奇型果の出現はみられなかつた。

著者

上藤 満宏 川口 岳芳

出版者

THE JAPANESE SOCIETY FOR HORTICULTURAL SCIENCE

雑誌

園芸学研究 (ISSN:13472658)

巻号頁・発行日

vol.18, no.3, pp.259-267, 2019 (Released:2019-09-30)

参考文献数

27

---

ミニトマト夏秋栽培におけるつやなし果の発生を抑制するため,着果促進剤(4-CPA)および遮光がつやなし果の発生に及ぼす影響について調査した.4-CPA処理におけるつやなし果発生率は,5~12%であり,無処理の22~39%と比較して有意に低かったことから,4-CPA処理は,つやなし果の発生抑制技術として有効と考えられた.また,遮光処理によって施設内の昇温を抑制した遮光区および調光区のつやなし果の発生率は7および9%であり,無遮光区の15%と比較して有意に低く,つやなし果の発生が最も多い9月の可販果収量は遮光処理した遮光区および調光区が株当たり0.8および1.0 kgであり,無遮光区の0.4 kgと比較して有意に多かった.これらのことから,遮光による昇温抑制は,つやなし果の発生抑制技術として有効と考えられた.遮光処理の方法について,強日射時のみ遮光する方法は,つやなし果の発生抑制効果に加えて,常時遮光する方法と比較して可販果収量が一時的に増加したことから,つやなし果の発生を抑制しつつ常時遮光による減収を回避する方法として有効であると考えられた.

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

---

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

---

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.