著者
Kazuki Yamazaki Rika Kitamura Tomohiro Suzuki Takeshi Kurokura Kenji Yamane
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.QH-079, (Released:2023-10-14)

Gladiolus (Gladiolus spp.) florets exhibit low ethylene sensitivity. Accordingly, the wilting of their tepals is an ethylene-independent process. Both trehalose and cycloheximide can extend the vase life of gladiolus florets. Floral senescence is probably regulated by programmed cell death. However, senescence-related genes have not been thoroughly investigated, except in ethylene-sensitive species. In this study, we analyzed the expression of senescence-associated genes by conducting transcriptome (RNA-seq) analysis. First, we examined the effects of 0.1 M trehalose (Tre), 300 μM cycloheximide (CHI), and 50 μM chloramphenicol (CAP) treatments on postharvest quality and senescence-related gene expression in gladiolus ‘Fujinoyuki’ cut florets. The Tre and CHI treatments extended the vase life of gladiolus florets by about 1 day, i.e., 30% of Cont. Tepals were sampled at 0 days (0d) and 2 days (2d) post-treatment. The RNA-seq analysis of floret tissues generated 81,136 unique sequences. Moreover, 2,892, 4,670, and 57 differentially expressed genes were identified from the 0d_Control (Cont) vs 2d_Cont, 2d_Cont vs 2d_CHI, and 2d_Cont vs 2d_Tre comparisons, respectively. Gene Ontology (GO) analysis suggested that cysteine-type endopeptidase activity was significantly higher for 2d_Cont than for 0d. Additionally, the 0d vs 2d_Cont comparison showed the cell wall-related GO terms were more enriched for 2d_Cont. The Kyoto Encyclopedia of Genes and Genomes analysis revealed an increase in the expression of sucrose synthesis-related genes in the 2d_Cont samples. Among the genes involved in starch and sucrose metabolism, the genes mediating cell wall degradation were more actively expressed in the 2d_Cont samples than in the 2d_CHI samples. The fragments per kilobase per million reads (FPKM) values were used to select candidate senescence-related gene families, including the cysteine protease, invertase, peroxidase, pectinesterase, and transcription factor (NAC [no apical meristem (NAM), Arabidopsis transcription activation factor (ATAF), and cup-shaped cotyledon (CUC)] and WRKY) families. The expression levels of transcription factor genes, including NAC 048, 68, 073 and WRKY 6, 11, 24, were validated by qPCR. The expression of these NAC and WRKY transcription factor genes was upregulated by CHI, suggesting their involvement in senescence or side reactions in gladiolus tepals. This study revealed several candidate genes and associated GO terms for senescence of cut florets, but further study is needed, especially on key genes, including transcription factors.
著者
Kanjana Worarad Xiaonan Xie Inna Martha Rumainum Chairat Burana Kenji Yamane
出版者
一般社団法人 園芸学会
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.OKD-043, (Released:2016-12-29)
被引用文献数
5

Fluridone, an inhibitor of carotenoid biosynthesis, is known to prevent abscisic acid (ABA) biosynthesis and to affect the germination and dormancy of seeds in several plant species. This study investigated the effects of fluridone on seed germination of the ornamental peach ‘Yaguchi’, and on the transcript levels of genes related to seed dormancy in this plant. Seeds were rinsed for 2 days under running tap water (RS), then soaked for 1 day in 100 μM fluridone (F), and kept at 5°C for 2 weeks (2W). The germination rate significantly increased from 0% to 9.5% in the RS+F treatment and to 71.4% in the RS+F+2W treatment, while no germination occurred in the RS and RS+2W treatments. Seedlings in RS+F and RS+F+2W treatments formed dwarf shoots, i.e. about 10 cm, and morphological lesions on the leaves. The ABA content in embryonic axes decreased after RS and increased with RS+2W. It was decreased by the RS+F+2W treatment. RS+F+2W downregulated ABA-hy3, which encodes enzymes with key roles in ABA catabolism, while its effects on 9-cis-epoxycarotenoid dioxygenase (NCED1) in relation to ABA synthesis fluctuated. In contrast, Empfindlicherim Dunkelroten Licht 1 (EID1) was upregulated after fluridone treatment, suggesting that fluridone may activate positive ABA signaling pathways. Expression of GA2-oxidase8 (GA2-ox8) was not affected by fluridone. MADS-box protein JOINTLESS (LeMADS) and Late embryogenesis abundant protein D-34 (LEA D-34) were downregulated in the RS+F+2W treatment, suggesting that the expression of these genes are controlled by low temperature and the ABA inhibitor, and are involved in seed dormancy. These results suggest that ABA inhibitor treatments can be an alternative method to promote germination by controlling ABA content and its metabolism, and consequently changing expression of certain ABA- and dormancy-related genes including ABA-hy3, EID1, LeMADS, and LEA D-34, even under insufficient chilling conditions.
著者
Evelyn Villanueva Nozomi Fujibayashi-Yoshii Suguru Matsuzaki Kazuki Yamazaki Chairat Burana Kenji Yamane
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
vol.88, no.2, pp.276-283, 2019 (Released:2019-04-23)
参考文献数
23
被引用文献数
7

The postharvest physiology of cut astilbe inflorescences (Astilbe × arendsii), which consist of many small florets with a short vase life, was studied in response to treatments to extend their vase life. Exogenous ethylene treatment at 0.3 μL·L−1 for 7 h did not affect the senescence of inflorescences or leaves of five cultivars and 0.2 mM silver thiosulfate for 2 h did not improve the quality of inflorescences of three cultivars, which indicated that ethylene is not a critical factor for senescence in astilbe florets. Continuous treatment with 2% sucrose or 2% trehalose solutions prolonged the cut inflorescence vase life of one or two of five astilbe cultivars, respectively. Pulse treatment with 2% trehalose in combination with 6% sucrose increased total soluble sugar contents from 11.4 to 57.6 mg·g−1 FW and raised the respiration rate of inflorescences from 15.3 to 28.4 μmol CO2·h−1·g−1 FW at 2 days after harvest (DAH) in the cultivar ‘Gloria Purpurea’. However, the effects of pulse treatment diminished at 4 DAH and extended the vase life from 4.0 days to a maximum of 5.6 days, which suggested that pulse treatments were inadequate to maintain sugar contents and respiration activity. Continuous treatment with 6% sucrose extended the vase life from 4.3 to 10.0 days and raised the chroma (C*) value of florets from 28.7 to 54.9 at 8 DAH. Continuous treatment with 2% trehalase + 4% sucrose markedly prolonged the vase life to 11.5 days and increased the C* value to 53.9 at 8 DAH. Under stereomicroscopic observation, continuous treatment with 2% trehalase + 4% sucrose maintained more vivid pink color of petals, styles, filaments and receptacles than those in control florets at 9 DAH. Combined treatment with 2% trehalose and 30 μM validamycin A, a potent inhibitor of trehalose metabolizing activity, induced severe wilting of florets and necrotic spots on leaves. Exogenous trehalose may be hydrolyzed by trehalose metabolizing activity in cut astilbe inflorescences. The results suggest that continuous treatment with trehalose and sucrose solutions is effective to maintain development and delay senescence of florets to extend the vase life of cut astilbe inflorescences.
著者
Evelyn Villanueva Nozomi Fujibayashi-Yoshii Suguru Matsuzaki Kazuki Yamazaki Chairat Burana Kenji Yamane
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-031, (Released:2018-12-07)
被引用文献数
7

The postharvest physiology of cut astilbe inflorescences (Astilbe × arendsii), which consist of many small florets with a short vase life, was studied in response to treatments to extend their vase life. Exogenous ethylene treatment at 0.3 μL·L−1 for 7 h did not affect the senescence of inflorescences or leaves of five cultivars and 0.2 mM silver thiosulfate for 2 h did not improve the quality of inflorescences of three cultivars, which indicated that ethylene is not a critical factor for senescence in astilbe florets. Continuous treatment with 2% sucrose or 2% trehalose solutions prolonged the cut inflorescence vase life of one or two of five astilbe cultivars, respectively. Pulse treatment with 2% trehalose in combination with 6% sucrose increased total soluble sugar contents from 11.4 to 57.6 mg·g−1 FW and raised the respiration rate of inflorescences from 15.3 to 28.4 μmol CO2·h−1·g−1 FW at 2 days after harvest (DAH) in the cultivar ‘Gloria Purpurea’. However, the effects of pulse treatment diminished at 4 DAH and extended the vase life from 4.0 days to a maximum of 5.6 days, which suggested that pulse treatments were inadequate to maintain sugar contents and respiration activity. Continuous treatment with 6% sucrose extended the vase life from 4.3 to 10.0 days and raised the chroma (C*) value of florets from 28.7 to 54.9 at 8 DAH. Continuous treatment with 2% trehalase + 4% sucrose markedly prolonged the vase life to 11.5 days and increased the C* value to 53.9 at 8 DAH. Under stereomicroscopic observation, continuous treatment with 2% trehalase + 4% sucrose maintained more vivid pink color of petals, styles, filaments and receptacles than those in control florets at 9 DAH. Combined treatment with 2% trehalose and 30 μM validamycin A, a potent inhibitor of trehalose metabolizing activity, induced severe wilting of florets and necrotic spots on leaves. Exogenous trehalose may be hydrolyzed by trehalose metabolizing activity in cut astilbe inflorescences. The results suggest that continuous treatment with trehalose and sucrose solutions is effective to maintain development and delay senescence of florets to extend the vase life of cut astilbe inflorescences.
著者
Kenji Yamane Kitaro Sumida Yuri Terui Nagisa Kojima Chairat Burana Takeshi Kurokura
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.OKD-151, (Released:2018-02-08)
被引用文献数
2

Temperature regimes that cause malformed flowers were examined and histological observation was carried out at the developmental stage of flowers by using mutants of the potted carnation (Dianthus caryophyllus L.) ‘Cherry’ producing malformed flowers according to cultivation season. Plants of normal (WT) and malformed (mlf) lines were grown under several temperature regimes. All WT plants produced normal flowers, whereas mlf lines showed a variety of malformed floral phenotypes, including phyllody-like proliferated sepaloids, proliferated petaloids, proliferated pistillodes with or without petals, secondary flower formation, and a flattened receptacle. In Experiment 1, mlf plants produced no malformed flowers when grown under constant 26°C, whereas 34.2% of mlf plants produced malformed flowers at 14–16/12°C (day/night, natural light). Malformation frequency was slightly lower at a night temperature of 5°C compared with 14–16/12°C. When malformed mlf plants were transferred from 17/5°C to 23/18°C, flower malformation was alleviated. Conversely, when mlf plants grown under constant 26°C with a normal phenotype were transferred to 17/12°C, flower malformation was induced. Thus, flower malformation was reversible depending on the temperature regime. In Experiment 2, 92.2% of mlf plants produced malformed flowers under constant 15°C, whereas 3.1% and 1.3% showed flower malformation when grown under constant 20°C and 25/20°C, respectively. These findings suggested that the threshold for flower malformation is between 15°C and 20°C. Observation of shoot apices by optical microscopy and scanning electron microscopy revealed morphological differences between WT and mlf after sepal formation. Petal primordia were not visible in mlf plants at 15°C, although petal primordia were initiated in WT. After this stage, flower malformations observed in mlf included undeveloped petals, undeveloped or irregularly developed stamens, secondary flower primordia formation, and completely irregular arrangement of undeveloped flower organs. No phytoplasma was detected by PCR, indicating that it could not be the causal agent of the abnormal phenotypes. This is the first report of mutant flower phenotypes dependent on temperature and induced by only a 5°C difference within optimal growing-temperature regimes in carnations.
著者
Inna Martha Rumainum Kanjana Worarad Yoshikazu Yamaki Kenji Yamane
出版者
一般社団法人 園芸学会
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.MI-077, (Released:2015-11-21)
被引用文献数
6

A red-fleshed peach (Prunus persica L. Batsch ‘Tenshin Suimitsuto’; ‘Tianjinshuimi’ in Chinese) was used to study the mechanisms of skin and flesh pigmentation. Anthocyanin accumulation was detected at the pre-endocarp-hardening and maturation stages in skin, while it appeared from maturation stage in flesh. The flesh at harvest stage contained approximately 1.1 mg·g−1 FW of anthocyanin. In contrast, flavonoid and phenolic compounds were found in all stages. The final phenolics concentration was 1.6 mg·g−1 FW. To study the effects of light, fruits were on-tree bagged in double-layered paper bags. The total anthocyanin content in the skin was significantly lowered by bagging, but not in the flesh. This suggested that flesh tissue pigmentation was less sensitive to light intensity than that of skin tissue, and thus, anthocyanin accumulation in flesh occurred even under low light conditions. Dark treatments, such as triple-layered paper bagging, significantly reduced anthocyanin and phenolic concentrations in the skin and flesh. A combined treatment of darkness and an auxin polar transport inhibitor, 2,3,5-triiodobenzoic acid (TIBA), had no effect on anthocyanin concentration in skin and flesh. However, total flavonoids in the skin was increased by TIBA treatments under darkness. Factors affecting anthocyanin accumulation in the flesh tissue are discussed.