TY - JOUR
T1 - Deep complex morphophysiological dormancy in seeds of Viburnum plicatum var. formosanum (Adoxaceae) from subtropical mountains
AU - Chen, Shun Ying
AU - Liu, Chiung Pin
AU - Baskin, Carol C.
AU - Chien, Ching Te
N1 - Publisher Copyright:
Copyright © The Author(s), 2021.
PY - 2021/9/15
Y1 - 2021/9/15
N2 - Viburnum is a temperate-zone genus that also occurs in mountains of South America and Malesia, and seeds of many species have morphophysiological dormancy (MPD). Information on the level of MPD in seeds of species in various clades of Viburnum potentially would increase our understanding of the evolutionary relationships between the nine levels of MPD. Our aim was to determine the level of MPD in seeds of Viburnum plicatum var. formosanum that is endemic to mountains (1800-3000 m a.s.l.) in Taiwan and a member of the Lutescentia clade. The temperature requirements for embryo growth and root and shoot emergence and response of seeds to gibberellic acid (GA) were determined. No fresh seeds germinated during 16 weeks of incubation at 15/5, 20/10, 25/15, 30/20 or 25°C. Embryo growth and root emergence occurred during moist cold stratification at 5°C or at a temperature sequence of 15/5 to 5°C. During cold stratification, embryos length increased from 0.76 ± 0.06 to 3.40 ± 0.26 mm and the embryo length:seed length ratio from 0.20 ± 0.02 to 0.68 ± 0.07. In a temperature sequence simulating field conditions, embryos grew inside seeds at 5°C, roots emerged at 15/5°C and shoots emerged at 20/10°C. The optimum temperature for embryo growth was 5°C. Neither GA3 nor GA4 was effective in promoting root emergence. We conclude that seeds of V. plicatum var. formosanum have deep complex MPD, which is a first report for Viburnum. Dormancy release during the cool season at high elevations helps to ensure that seeds germinate at the beginning of the warm season.
AB - Viburnum is a temperate-zone genus that also occurs in mountains of South America and Malesia, and seeds of many species have morphophysiological dormancy (MPD). Information on the level of MPD in seeds of species in various clades of Viburnum potentially would increase our understanding of the evolutionary relationships between the nine levels of MPD. Our aim was to determine the level of MPD in seeds of Viburnum plicatum var. formosanum that is endemic to mountains (1800-3000 m a.s.l.) in Taiwan and a member of the Lutescentia clade. The temperature requirements for embryo growth and root and shoot emergence and response of seeds to gibberellic acid (GA) were determined. No fresh seeds germinated during 16 weeks of incubation at 15/5, 20/10, 25/15, 30/20 or 25°C. Embryo growth and root emergence occurred during moist cold stratification at 5°C or at a temperature sequence of 15/5 to 5°C. During cold stratification, embryos length increased from 0.76 ± 0.06 to 3.40 ± 0.26 mm and the embryo length:seed length ratio from 0.20 ± 0.02 to 0.68 ± 0.07. In a temperature sequence simulating field conditions, embryos grew inside seeds at 5°C, roots emerged at 15/5°C and shoots emerged at 20/10°C. The optimum temperature for embryo growth was 5°C. Neither GA3 nor GA4 was effective in promoting root emergence. We conclude that seeds of V. plicatum var. formosanum have deep complex MPD, which is a first report for Viburnum. Dormancy release during the cool season at high elevations helps to ensure that seeds germinate at the beginning of the warm season.
KW - Gibberellins
KW - Moist cold stratification
KW - Seed germination
KW - Underdeveloped embryo
UR - http://www.scopus.com/inward/record.url?scp=85115164374&partnerID=8YFLogxK
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U2 - 10.1017/S0960258521000180
DO - 10.1017/S0960258521000180
M3 - Article
AN - SCOPUS:85115164374
SN - 0960-2585
VL - 31
SP - 236
EP - 242
JO - Seed Science Research
JF - Seed Science Research
IS - 3
ER -