著者

Masahiro Kamimori Takeshi Isobe Hiroshi Yakushiji

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

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

参考文献数

27

被引用文献数

1

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

著者

Takaya Ishii Miki Suto Natsuki Suzuki 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-343, (Released:2022-07-14)

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Onion (Allium cepa L.) is one of the most important vegetable crops in the world, and its cultivation is roughly divided into two types: autumn- (overwinter) and spring-sowing. In this study, we compared the changes in plant growth and bulb development of four short-day and intermediate-day onion cultivars under two years of varying environmental conditions to understand autumn-sowing cultivation and growth characteristics. A comparison of the growth parameters of the four cultivars throughout the growth period revealed that the increase in total leaf number and area, and plant height were almost completely inhibited in winter. In spring, these growth parameters increased rapidly in the early maturing cultivars and reached a plateau depending on the cultivar’s maturity type, as previously shown in spring-sowing cultivation. It is known that AcFT1 and AcFT4 play a key role in the bulb development of cultivated onions. Therefore, we conducted expression analysis of these genes for the four cultivars grown in the field and confirmed that AcFT1 was expressed following the maturity, irrespective of cultivation methods. We also analyzed AcGI expression in leaf blades, and a certain relationship between changes in bulb development and AcGI expression was observed. Correlation analysis of AcFT1 expression and total leaf number and area was conducted, and strong positive correlations were observed. In conclusion, our study demonstrated genetically that leaf number and area are important for inducing onion bulb development.

著者

Daiki Matsumoto Seita Shimizu Aoi Shimazaki Kohei Ito Satoshi Taira

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-385, (Released:2022-07-14)

被引用文献数

3

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Akebia trifoliata is cultivated locally in few areas of Japan. Artificial pollination is considered indispensable for stable fruit production, as Akebia spp. exhibit self-incompatibility (SI). However, little is known about the reproductive physiology required for effective artificial pollination. In this study, we investigated the effects of self-pollen contamination on the fruit set of ‘Fuji Murasaki’ (A. trifoliata), one of the main lines in Yamagata Prefecture, Japan. Both the self- and cross-pollen tubes reached the base of the ovary and penetrated the ovules at 10 days after pollination, indicating that A. trifoliata exhibits late-acting SI. Self-pollination one day before cross-pollination completely inhibited fruit set, while self-pollination one day after cross-pollination did not inhibit fruit set in both 2016 and 2020, indicating interference in cross-pollination by self-pollen contamination. Fruit set rates for artificial pollination using a 1:1 mix of self- and cross-pollen were significantly lower than those that used non-contaminated cross-pollen in both 2016 and 2019, but were comparable when using a 1:1 mix of lycopodium powder and cross-pollen. The seed number of fruit resulting from mixed pollination was not significantly lower than that of fruit resulting from cross-pollination. Interestingly, 1:1 mixed pollination of self- and cross-pollen sometimes yielded abnormal fruits with an apex that remained pale and did not soften. These results suggest that excessive self-pollen contamination in artificial pollination may not be desirable for A. trifoliata fruit production.

著者

Megumi Ogawa Rihito Takisawa

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-368, (Released:2022-06-25)

被引用文献数

2

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Artificially occurring parthenocarpy can be induced by exogenous application of plant hormones and is useful in the fruit production of many fruit crops and fruit trees. In cucumber (Cucumis sativus L.), a model species in the Cucurbitaceae family, the plant hormones auxin, gibberellin, cytokinin, and brassinosteroids are known to induce parthenocarpy. In tropical squash (Cucurbita moschata L.), synthetic auxins are known to induce parthenocarpy, but the effects of gibberellin, cytokinin, and brassinosteroids are still unknown. In addition, there are few published reports on the quality of parthenocarpic fruits induced by plant hormones in tropical squash, and the effects of these hormones remain largely unknown. In this study, we examined the effects of gibberellin, cytokinin, and brassinosteroids on the parthenocarpy of tropical squash and characterized the parthenocarpic fruits induced by the plant hormones. First, we evaluated fruit set and development in unpollinated fruits of ‘Kogiku’, a tropical squash cultivar, treated with gibberellic acid (GA3), a synthetic cytokinin-like substance, N-(2-chloro-4-pyridyl)-N′-phenylurea (CPPU), and brassinolide (BL). CPPU promoted parthenocarpy, but GA3 and BL did not, showing that cytokinin works as an important factor for parthenocarpy in tropical squash. Next, we investigated the quality of parthenocarpic fruits from ‘Kogiku’ induced by a synthetic auxin, 1-naphthylacetic acid (NAA), and CPPU. Total soluble solids and myo-inositol of NAA-treated parthenocarpic fruit were higher than those of pollinated fruits, whereas fructose of NAA-treated parthenocarpic fruit and fructose and glucose of CPPU-treated parthenocarpic fruits were significantly lower than those of pollinated fruits. These results showed that parthenocarpy of tropical squash induced by auxin and cytokinin had differing effects on fruit quality.

著者

Katsuhiko Inamoto Kaori Nagasuga Takayoshi Yano

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-372, (Released:2022-06-25)

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We investigated the effects of CO2 enrichment on photosynthesis, growth, and dry matter accumulation in the Oriental hybrid lily ‘Siberia’. The photosynthetic rate increased as the CO2 concentration was elevated compared to the ambient level. The increase in the photosynthetic rate was greater in the low concentration range and lower in the high concentration range. The relationship between the light intensity-photosynthetic rate and temperature-photosynthetic rate was investigated under different CO2 concentrations. The entire light-photosynthesis and temperature-photosynthesis curves moved toward a considerably higher photosynthetic rate when the CO2 concentration was increased from 380 ppm to 1000 ppm. In contrast, when the CO2 concentration was increased from 1000 ppm to 2000 ppm, the increase in the entire light-photosynthesis curve was small. The relationship between the CO2 concentration and the maximum temperature point of the photosynthetic rate was unclear. We also cultured ‘Siberia’ lily plants with and/or without CO2 enrichment (1500 ppm) altered before (the early stage) and after (the late stage) the visible flower bud stage. The CO2 enrichment increased dry weights dry weight/fresh weight ratios of whole plants, and individual parts at flowering, resulting in improved cut flower quality and enlargement of the mother bulb and daughter bulblets. The effective period of CO2 enrichment was after the visible flower bud stage. In cases where CO2 enrichment was effective for dry matter accumulation, the dry matter distribution ratios of the mother bulb and daughter bulblets to the whole plant were high, and those of the leaves, stem, and flower buds were low. The relative growth rate and net assimilation rate from planting to the flowering stage were increased with CO2 enrichment applied after the visible flower bud stage, indicating that the dry matter accumulation and photosynthesis were enhanced. Finally, the issues that need to be addressed for applying practical CO2 enrichment technology to various lilies are discussed.

著者

Saeko Konishi-Sugita Kayo Sato Etsuko Mori Yuko Abe Miho Hazebayashi Kenji Gomi Mitsuaki Tabuchi Gan Kisaki Tetsuo Fukuda Tetsuro Manabe Kohei Hamano Mamoru Ohtani Katsuhiko Suezawa Kazuya Akimitsu Ikuo Kataoka

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-340, (Released:2022-06-15)

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The pathogenic bacterium Pseudomonas syrinage pv. actinidiae causes bacterial canker disease, which is the most damaging disease afflicting kiwifruit (Actinidia chinensis). The most prevalent strain is biovar 3 (Psa3), which is highly pathogenic. Therefore, Psa3-resistant varieties of kiwifruit are urgently needed. A previous study reported that Actinidia rufa, a wild Japanese species related to kiwifruit, is highly resistant to Psa3. Genome-wide DNA markers may be useful to locate the loci that confer Psa3 resistance. Therefore, in the present study, we used published kiwifruit genome sequence information to design 1,101 simple sequence repeat (SSR) markers covering the entire kiwifruit genome in silico. We next examined DNA polymorphisms in more than 1,000 polymerase chain reaction products for potential use as SSR markers among A. rufa Fuchu and A. chinensis FCM1, a pollen-providing parent Fuchu A. chinensis male 1, and other kiwifruit cultivars in order to develop Psa3 resistant kiwifruit cultivars. We finally obtained 351 polymorphic markers, in the entire kiwifruit genome, which can be applied to produce next-generation kiwifruit cultivars, including Psa3-resistant cultivars.

著者

Atsu Yamasaki Junko Kaneyoshi Michiharu Nakano Akira Kitajima

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-284, (Released:2022-06-01)

被引用文献数

1

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Mukaku Kishu–type seedlessness in citrus (Citrus L.) is characterized by the formation of small and edible seeds (type A seeds) with an immature seed coat and arrest of embryo development at an early stage. We investigated the effect of high temperature on embryo and seed development in the Mukaku Kishu–type seedless cultivar ‘Southern Yellow’ over a period of four years. In outdoor-grown trees, embryos at the zygote and proembryo stages were observed at 10 weeks after pollination (WAP), and embryo development was largely arrested at 18 WAP; as a result, only type A seeds formed. In glasshouse-grown trees, globular-stage embryos were observed at 10 WAP, and globular- to cotyledon-stage embryos developed by 18 WAP. The day temperature in the glasshouse was higher than outdoors. Seeds developed in the fruit of trees transferred into a glasshouse at 0–2, 0–4, or 2–4 WAP, but not 4–8 WAP. High temperature before flowering had no effect on seed development. We conclude that high temperature at 0–4 WAP releases the arrest of embryo development after 10 WAP in ‘Southern Yellow’.

著者

Hiroki Matsuo Keiji Mine Taro Sano Hirotsugu Yoneda Yosuke Yoshioka

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-363, (Released:2022-05-31)

被引用文献数

2

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Anthracnose, caused by the fungal pathogen Colletotrichum orbiculare, is one of the most severe diseases in watermelon (Citrullus lanatus) cultivation in Japan. Genetically conferred host resistance is the best way to control it. To develop new cultivars with high resistance, identification of promising sources of resistance is important. We focused on an old Japanese cultivar, ‘Tanso Teikosei’ (NR28), with high resistance, preserved at the Nara Prefecture Agricultural Research and Development Center, evaluated its resistance to diverse C. orbiculare strains distributed in Japan, and revealed the inheritance of its resistance. NR28 and two other accessions were resistant to the highly virulent MAFF 306737 strain. NR28 was also resistant to 16 other strains collected from various regions of Japan. Many strains caused severe symptoms and wilting in susceptible accessions, including the popular Japanese F1 cultivar WF01. CAPS marker analysis indicated that NR28 and the two other resistant accessions were homozygous for the resistance allele of Cla001017, previously reported as the gene responsible for resistance to US race 1. Susceptible accessions were homozygous for the susceptibility allele at Cla001017. Segregation analyses using F2 and BC1F1 lines derived from crosses between NR28 and a susceptible accession suggested that the dominant mutant allele of Cla001017 caused the high resistance of NR28. In contrast, NR28 and other resistant accessions homozygous for the resistance allele of Cla001017 were highly susceptible to two strains sampled in Iwate Prefecture. This suggests that these strains have overcome the Cla001017 resistance allele, as have strains of C. orbiculare classified as US race 2. NR28 and the two other resistant accessions are promising materials for breeding resistance in diverse C. orbiculare strains distributed in Japan that have similar pathogenicity to US race 1. The CAPS marker that we designed in this study offers efficient analysis for watermelon breeding.

著者

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-R019, (Released:2022-05-31)

被引用文献数

4

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The fresh fruit yield of tomatoes (Solanum lycopersicum) is determined by yield components and related traits. In low-truss cultivation in Japan, light use efficiency in the same cultivar is not significantly affected by plant density or seedling stage at transplanting. Total dry-matter production equals light use efficiency × light intercepted by plants. Light interception is determined by leaf area index and the light extinction coefficient in the plant canopy. Light use efficiency is determined by leaf photosynthetic rate and light extinction coefficient. Light use efficiency is expressed as a function of daytime CO2 concentration. The high yield of modern tomato cultivars in the Netherlands is due to an increase in total dry matter production of plants, not to an increase in dry matter partitioning of fruits. An increase in the photosynthetic rate and a decrease in the light extinction coefficient may have increased light use efficiency among Dutch cultivars. Although modern Japanese cultivars have a high content of both water and soluble solids of fruits, yield has not increased. Since the yield of greenhouse tomatoes in Japan has increased little since the 1980s, Japanese researchers have attempted to improve the yield using current Japanese cultivars. Crop growth models can help management decisions on cultural practices, control of greenhouse climate, fertilization, and irrigation. Several models of tomato growth including TOMSIM and TOMGRO have been developed. A growth model based on the relationships among yield components and related traits has been developed to predict dry matter production and yield of greenhouse tomatoes. The model recommended a leaf area index with the highest dry matter production at a certain solar radiation. To improve yield of greenhouse tomatoes by using the model, a one-year experiment was carried out in a greenhouse. The annual yield of tomatoes with Brix at least 5° was at least 50 kg·m−2 for a popular Japanese cultivar, ‘CF Momotaro York’. For the near future, the growth models show promise for growers in helping yield improvement and crop management in greenhouses.

著者

Maria Suzuki Kanae Masuda Hideaki Asakuma Kouki Takeshita Kohei Baba Yasutaka Kubo Koichiro Ushijima Seiichi Uchida Takashi Akagi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-323, (Released:2022-05-25)

被引用文献数

6

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In contrast to the progress in the research on physiological disorders relating to shelf life in fruit crops, it has been difficult to non-destructively predict their occurrence. Recent high-tech instruments have gradually enabled non-destructive predictions for various disorders in some crops, while there are still issues in terms of efficiency and costs. Here, we propose application of a deep neural network (or simply deep learning) to simple RGB images to predict a severe fruit disorder in persimmon, rapid over-softening. With 1,080 RGB images of ‘Soshu’ persimmon fruits, three convolutional neural networks (CNN) were examined to predict rapid over-softened fruits with a binary classification and the date to fruit softening. All of the examined CNN models worked successfully for binary classification of the rapid over-softened fruits and the controls with > 80% accuracy using multiple criteria. Furthermore, the prediction values (or confidence) in the binary classification were correlated to the date to fruit softening. Although the features for classification by deep learning have been thought to be in a black box by conventional standards, recent feature visualization methods (or “explainable” deep learning) has allowed identification of the relevant regions in the original images. We applied Grad-CAM, Guided backpropagation, and layer-wise relevance propagation (LRP), to find early symptoms for CNNs classification of rapid over-softened fruits. The focus on the relevant regions tended to be on color unevenness on the surface of the fruit, especially in the peripheral regions. These results suggest that deep learning frameworks could potentially provide new insights into early physiological symptoms of which researchers are unaware.

著者

Ryo Norikoshi Katsunori Kohata Tomoko Niki Kazuo Ichimura

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-347, (Released:2022-05-25)

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Flower opening is associated with the expansion of petal cells. To understand the role played by soluble carbohydrates during cell expansion associated with petal growth, changes in soluble carbohydrate concentrations in petal limbs during flower opening in Phlox drummondii were investigated. The size of adaxial and abaxial epidermal cells in the petal limbs gradually increased during flower opening. 2-C-Methyl-d-erythritol (2-C-ME) was identified using 1H-NMR in P. drummondii petals. 2-C-ME was the most abundant carbohydrate in the petal limbs at five developmental stages, with the concentration of glucose the second highest, although the concentration of the latter was half of that of the 2-C-ME concentration in all five stages. The concentrations of 2-C-ME and glucose increased during flower opening. In contrast, inorganic ion concentrations did not increase during flower opening. The osmotic potential of petal limbs decreased considerably during the final stage of flower opening; this decrease could in part be attributed to the increasing 2-C-ME concentration. Transmission electron microscopic observations showed that the petal limb cells in open flowers were occupied primarily by the vacuole. The concentration of 2-C-ME in the vacuole was estimated to be 131 mM, which was much higher than the concentrations of the other carbohydrates. We conclude that the accumulation of 2-C-ME in the vacuole at a high concentration acts as an osmoticum, decreasing the osmotic potential of petal limbs and thereby increasing turgor pressure, which is thought to be involved in cell expansion of petal limbs during flower opening.

著者

Orawan Pimsorn Somsak Kramchote Patcharaporn Suwor

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-359, (Released:2022-05-25)

被引用文献数

1

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Lime (Citrus aurantiifolia var. Pan) fruits were coated with Aloe vera gel (AVG) at 0 (distilled water as control), 10, 20, 30, 40, and 50% concentration as a 5 min dip and stored at ambient temperature (29 ± 1°C, 74 ± 5% RH) for 16 days. AVG coating markedly slowed fruit yellowing based on color scores and CIE L*, a*, and b* values, resulting in an increase in shelf life of about four days longer than that of the control (10 days). It did not significantly affect other fruit responses; AVG-coated and uncoated fruit had comparable weight loss, juice content, total soluble solids (TSS), titratable acidity (TA), and vitamin C content. Thus, AVG coating improved shelf life of lime primarily through delayed yellowing without adverse effects on other physicochemical attributes.

著者

Hikaru Matsumoto Yoshinori Ikoma

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-364, (Released:2022-05-19)

被引用文献数

3

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Combined treatment with gibberellin (GA) and prohydrojasmon (PDJ) is effective at reducing peel puffing in satsuma mandarin (Citrus unshiu Marc.). However, the effect of this treatment on volatiles remains unknown. In satsuma mandarin, dimethyl sulfide (DMS) is a key flavor compound. In this study, the effects of combined treatment with GA and PDJ on the content of volatiles, DMS, and S-methylmethionine (SMM), a precursor of DMS, in the juice sacs of satsuma mandarin were investigated. Mixtures of GA (1, 3.3, or 5 mg·L−1) and PDJ (25 or 50 mg·L−1) were applied to ‘Okitsu-wase’ and ‘Aoshima’ in mid-September. Gas chromatography-mass spectrometry analysis showed that among the volatiles, DMS content was reduced by the treatment, and was below the DMS odor threshold in several treatments. In ‘Okitsu-wase’, the DMS content in treated fruit was 1/3 to 1/17 of the control. In the treatment with GA and 50 mg·L−1 PDJ, a reduction in DMS content was observed until mid-November, irrespective of GA concentration, whereas in the treatment with 1 mg·L−1 GA and 25 mg·L−1 PDJ, the reduction was observed only until early November. In ‘Aoshima’, the DMS content was also reduced by the treatments, but in the treatment with 1 mg·L−1 GA and 50 mg·L−1 PDJ, the reduction was observed only until mid-November. Although the applied treatments delayed color development by approximately 1–2 weeks, this delay was not related to a reduction in DMS content. The effects on SMM and methionine content were small or negligible. As DMS has a strong odor, with trace amounts affecting fruit flavor, controlling DMS content is important. This study revealed that combined treatment with GA and PDJ reduced the accumulation of DMS in the juice sacs of satsuma mandarin fruits.

著者

Kohei Mochida Akira Nakatsuka Tetsuya Kako Nobuo Kobayashi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-366, (Released:2022-04-15)

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Tree peony (Paeonia spp.) is a highly ornamental shrub originally from China. Its cultivars are classified into four groups: Chinese, Japanese, French, and American, based on morphological characteristics and geographic location. The French and American cultivars were developed by crossing the wild species P. lutea Delavay ex Franch. and P. delavayi Franch. with Japanese and Chinese cultivars. In this study, we evaluated phenetic relationships among major cultivar groups in the genus Paeonia L., using a dendrogram reconstructed from band pattern data for random amplified polymorphic DNA (RAPD) markers developed in a previous study. We also developed two sequence tagged site (STS) markers using RAPD markers specific to the French and American tree peony cultivar groups and an intersubgeneric hybrid. The former is an LuDeB marker able to detect the genetic relationship with P. lutea and P. delavayi, and the latter is an HPB marker able to identify the cpDNA of herbaceous peony in intersubgeneric hybrid cultivars between herbaceous and tree peony. The possession of bands obtained in this study also supported the breeding history of cultivar development in the genus Paeonia.

著者

Munekazu Kishimoto Tetsunan Yamamoto Yuta Kobayashi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-314, (Released:2022-01-28)

被引用文献数

5

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In grapes, the ripening time of bunches on lateral or secondary induced shoots, led by simultaneous treatments of current shoot cutting and flower cluster removal, is typically delayed until the cooler seasons. The aim of this study was to estimate the effects of lateral or secondary induced shoot use in the cultivation of ‘Merlot’ grapevine phenology, including number of bunches and weight, yield, and fruit quality. The timings of flowering, coloration and harvest of lateral and secondary induced shoot grapes were delayed by around one month compared with those of vines grown under standard cultivation, which were used as a control. However, there were substantial differences between treatments in terms of number of bunches and weight, yield, and fruit quality. When lateral shoots grew after the current shoot was cut and the flower clusters were removed, the number of bunches decreased, and yield was significantly reduced. In contrast, when the secondary induced shoot germinated after the current shoot, flower clusters, and growing lateral shoots were removed, a stable number of bunches was observed and there was not a severe decrease in yield. Skin anthocyanin content in both the lateral shoot and secondary induced shoot grape berries was increased compared with control. This effect was comparatively stronger in secondary induced shoot grapes subjected to comparatively lower air temperatures during ripening. The results of this study underscore the importance of discriminating between lateral and secondary induced shoots in the process of shifting grape ripening to a cooler season by removing current shoots and flower clusters.

著者

Kyohei Kanamaru Kaoru Kohyama Kunihiko Konisho Katsuaki Izumi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-256, (Released:2021-04-02)

被引用文献数

1

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We used instruments to analyze the texture of compressed samples obtained from the equatorial portion of apples cut in radial and tangential directions. The flesh firmness evaluation of apples using a penetrometer (Magness-Taylor type) showed a year-to-year correlation, and this was highly correlated with mechanical values, including maximum force (N) evaluated using two instruments in both the radial and tangential directions. On the other hand, no significant relationship between the mechanical values obtained from the instruments and the sensory test results of flesh texture was observed. We adopted a crispness index (CI) value to characterize the mechanical response during the penetration test. The CI value was not correlated with most of the mechanical parameters in the Rheoner analysis. Additionally, we used a TA.XTplus texture analyzer to obtain mechanical and acoustic responses during the penetration test. The maximum and average acoustic pressures (dB) were not correlated with the mechanical parameters. There was a significant correlation between the acoustic profiles and the CI values obtained from the instruments. These results revealed that the CI and acoustic profiles were physical responses that differed from mechanical ones when measuring the flesh texture of apple fruit. In this study, the CI and acoustic pressure were associated with the sensory test results of flesh texture, suggesting that these parameters were effective for objectively evaluating the flesh texture of apples. The cultivars and selections evaluated as having high crunchiness by sensory test showed relatively high CI values and acoustic pressure. In addition, the CI value showed a significant year-to-year correlation (r = 0.68**), implying that it was one of the genetic characteristics responsible for the flesh texture of apples.

著者

水ノ江 雄輝 久保田 渉誠 菅野 明 尾崎 行生

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

vol.84, no.2, pp.140-147, 2015 (Released:2015-04-21)

参考文献数

32

被引用文献数

6 11

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シクラメン(Cyclamen persicum Mill.)において,自然突然変異による複数の種類の八重咲き品種が作出されている.我々は八重咲きシクラメンの形態的特徴と器官数を調査し,“雄蕊弁化型”,“萼弁化型”および“whorl 2 における花弁増加型”の 3 タイプに分類した.形態観察の結果,雄蕊の弁化と萼の弁化とが同時に起こっている個体は認められなかった.次に,一重咲きおよび雄蕊弁化型八重咲きシクラメンの花芽から 3 種類の AG-like 遺伝子を単離し,それぞれの whorl における発現を比較した.一重咲きのwhorl 3 では,全ての AG-like 遺伝子が発現していたが,雄蕊弁化型の八重咲きでは 3 種類とも発現は認められなかった.whorl 4 では,一重咲きおよび八重咲き花の両方において 3 種類の AG-like 遺伝子の発現が認められたが,八重咲き花における発現量は一重咲き花よりも低かった.これらの結果は,自然発生の八重咲きシクラメンが ABC モデルによって説明できること,そして雄蕊の弁化は whorl 3 における AG-like 遺伝子の発現抑制に起因することを示唆する.

著者

Kyutaro Kishimoto

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-268, (Released:2021-05-22)

被引用文献数

4

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Many cut flowers are treated with an ethylene action inhibitor, silver thiosulfate (STS), to delay senescence and are shipped by dry transport that involves relatively easy loading. In addition, cut flowers are often treated with a mixture of sugar and germicide to improve their vase lives. Exogenous treatments of these compounds or drying by transport are thought to have various effects on cut flowers. This study investigated the effects of these post-harvest management methods on the scent emission of carnation (Dianthus caryophyllus L.) cut flowers. Under all the management conditions, the total scent emissions of cut flowers were highest on harvest days and then decreased, but major changes in their compositions were not observed. The decreases in scent emissions were thought to occur earlier than the known ethylene induction in carnation cut flowers, which is equivalent to the 4th day after harvest. The STS treatment had no effect on the scent emissions for some time after harvest, but suppressed the decreases in scent emission 4–8 days after harvest under the wet transport condition. It is likely that the decreases in scent emissions in carnation cut flowers occur in an ethylene-independent manner, but ethylene induction a few days after harvest further promotes decreases under wet transport conditions. STS may have suppressed the promotion of decreases due to ethylene. On the other hand, the treatment that assumed dry transport for one day dramatically promoted the decreases in scent emissions. Since the promoting effects were not affected by the STS treatment, they were considered to be ethylene-independent. A common sugar treatment with 1% glucose, sucrose, or fructose did not affect the scent emissions in the cut flowers. An isothiazolinonic germicide, which is a common cut flower germicide, did not affect the treatment. Considering the current post-harvest process, the duration of a noticeable scent in carnation cut flowers can be expected to be extended by adopting wet transport instead of dry transport.

著者

Yoshiyuki Muramatsu Satoshi Kubota

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-R016, (Released:2021-05-11)

被引用文献数

2

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Here, we describe the current status of energy-saving techniques in greenhouse heating and countermeasures for high summer temperatures, and then introduce an outline and the performance of a newly developed New Root-zone Environmental Control System (N.RECS) and the effects of this system on flower production. Temperature control techniques used in protected horticulture include those that control the air temperature of the entire greenhouse space and those that control the local temperature of the plants. The running costs of the air temperature control techniques are expensive and the cooling capacity in the summer are inadequate for actual cultivation. Local temperature control techniques have relatively low running costs and can adequately cool plants during high temperature periods, but they are crop-specific and not versatile. Therefore, we developed a N.RECS that can heat and cool the root-zone of various plants with low running costs. N.RECS was produced by combining aluminum heat exchange panels, insulated pot trays and an air-source heat pump cold/hot water supply system. By using N.RECS, the root-zone temperature was maintained at 25°C when the air temperature was about 5°C during the winter and cooled to below 23°C when the air temperature was about 35°C during the summer. Root-zone heating of six potted flowers and cut flowers in the winter promoted growth and flowering and achieved energy savings of about 30% compared to conventional heating.When the two flower species, which are susceptible to high temperature, were grown under high temperature conditions, about half of the plants died, but root-zone cooling allowed all the plants to grow healthily. Therefore, it is concluded that N.RECS is a practical system that allows for both energy-saving cultivation in the winter and cooling cultivation in the summer. In addition, root-zone temperature is an environmental control parameter that should be controlled in future agricultural production; by applying root-zone temperature control as a standard technology for agricultural production, the growth of plants can be controlled more flexibly and more energy can be saved.

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

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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.