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Seed dormancy in the early diverging eudicot Trochodendron aralioides (Trochodendraceae)

Published online by Cambridge University Press:  22 February 2007

Jerry M. Baskin*
Affiliation:
Department of Biology, University of Kentucky, Lexington, KY 40506-0225, USA
Carol C. Baskin
Affiliation:
Department of Biology, University of Kentucky, Lexington, KY 40506-0225, USA Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546-0312, USA
Ching-Te Chien
Affiliation:
Division of Silviculture, Taiwan Forestry Research Institute, Taipei, 100, Taiwan
Shun-Ying Chen
Affiliation:
Division of Forest Biology, Taiwan Forestry Research Institute, Taipei, 100, Taiwan
*
*Correspondence Fax: +1 859 257 1717, Email: jmbask0@uky.edu

Abstract

The embryo length/seed length (E/S) ratio of the early diverging eudicot Trochodendron aralioides is 0.34. Embryos in fresh seeds were 0.36±0.01 mm long, and they increased in length by about 250% (in 20 d) before radicle emergence (germination) occurred, demonstrating that the embryo is underdeveloped at seed maturity. Seeds germinated to 95–100% at 20/10, 25/15 and 30/15°C in light in ≤4 weeks, without any pretreatment, but no seeds germinated in darkness. Thus, seeds of T. aralioides have morphological dormancy (MD), which is considered to be the primitive condition in seed plants, and MD probably has existed in the genus Trochodendron since its origin in the early Tertiary.

Type
Short Communication
Copyright
Copyright © Cambridge University Press 2006

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