Exogenous gibberellic acid shortening after-ripening process and promoting seed germination in a medicinal plant Panax notoginseng

Na Ge; Jin-Shan Jia; Ling Yang; Rong-Mei Huang; Qing-Yan Wang; Cui Chen; Zhen-Gui Meng; Long-Geng Li; Jun-Wen Chen

doi:10.1186/s12870-023-04084-3

Exogenous gibberellic acid shortening after-ripening process and promoting seed germination in a medicinal plant Panax notoginseng

BMC Plant Biol. 2023 Feb 1;23(1):67. doi: 10.1186/s12870-023-04084-3.

Authors

Na Ge^{1

2

3}, Jin-Shan Jia^{1

2

3}, Ling Yang^{1

2

3}, Rong-Mei Huang^{1

2

3}, Qing-Yan Wang^{1

2

3}, Cui Chen^{1

2

3}, Zhen-Gui Meng^{1

2

3}, Long-Geng Li^{1

2

3}, Jun-Wen Chen^{4

5

6}

Affiliations

¹ College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming, 650201, Yunnan, China.
² The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming, 650201, Yunnan, China.
³ National and Local Joint Engineering Research Center on Germplasm Innovation and Utilization of Chinese Medicinal Materials in Southwestern China, Yunnan Agricultural University, Yunnan, 650201, Kunming, China.
⁴ College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. cjw31412@hotmail.com.
⁵ The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. cjw31412@hotmail.com.
⁶ National and Local Joint Engineering Research Center on Germplasm Innovation and Utilization of Chinese Medicinal Materials in Southwestern China, Yunnan Agricultural University, Yunnan, 650201, Kunming, China. cjw31412@hotmail.com.

Abstract

Background: Panax notoginseng (Burk) F.H. Chen is an essential plant in the family of Araliaceae. Its seeds are classified as a type of morphophysiological dormancy (MPD), and are characterized by recalcitrance during the after-ripening process. However, it is not clear about the molecular mechanism on the after-ripening in recalcitrant seeds.

Results: In this study, exogenous supply of gibberellic acid (GA₃) with different concentrations shortened after-ripening process and promoted the germination of P. notoginseng seeds. Among the identified plant hormone metabolites, exogenous GA₃ results in an increased level of endogenous hormone GA₃ through permeation. A total of 2971 and 9827 differentially expressed genes (DEGs) were identified in response to 50 mg L^-1 GA₃ (LG) and 500 mg L^-1 GA₃ (HG) treatment, respectively, and the plant hormone signal and related metabolic pathways regulated by GA₃ was significantly enriched. Weighted gene co-expression network analysis (WGCNA) revealed that GA₃ treatment enhances GA biosynthesis and accumulation, while inhibiting the gene expression related to ABA signal transduction. This effect was associated with higher expression of crucial seed embryo development and cell wall loosening genes, Leafy Contyledon1 (LEC1), Late Embryogenesis Abundant (LEA), expansins (EXP) and Pectinesterase (PME).

Conclusions: Exogenous GA₃ application promotes germination and shorts the after-ripening process of P. notoginseng seeds by increasing GA₃ contents through permeation. Furthermore, the altered ratio of GA and ABA contributes to the development of the embryo, breaks the mechanical constraints of the seed coat and promotes the protrusion of the radicle in recalcitrant P. notoginseng seeds. These findings improve our knowledge of the contribution of GA to regulating the dormancy of MPD seeds during the after-ripening process, and provide new theoretical guidance for the application of recalcitrant seeds in agricultural production and storage.

Keywords: After-ripening process; Gibberellic acid; Morphophysiological dormancy; Panax notoginseng; Recalcitrant seeds; Transcriptome.

MeSH terms

Germination
Panax notoginseng*
Plant Growth Regulators
Plants, Medicinal*
Seeds

Substances

gibberellic acid
Plant Growth Regulators

Abstract

MeSH terms

Substances

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