- 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
- 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.