The great diversity in kinds of seed dormancy: A revision of the Nikolaeva-Baskin classification system for primary seed dormancy

Jerry M. Baskin, Carol C. Baskin

Research output: Contribution to journalReview articlepeer-review

43 Scopus citations


This review provides a revised and expanded word-formula system of whole-seed primary dormancy classification that integrates the scheme of Nikolaeva with that of Baskin and Baskin. Notable changes include the following. (1) The number of named tiers (layers) in the classification hierarchy is increased from three to seven. (2) Formulae are provided for the known kinds of dormancy. (3) Seven subclasses of class morphological dormancy are designated: 'dust seeds' of mycoheterotrophs, holoparasites and autotrophs; diaspores of palms; and seeds with cryptogeal germination are new to the system. (4) Level non-deep physiological dormancy (PD) has been divided into two sublevels, each containing three types, and Type 6 is new to the system. (5) Subclass epicotyl PD with two levels, each with three types, has been added to class PD. (6) Level deep (regular) PD is divided into two types. (7) The simple and complex levels of class morphophysiological dormancy (MPD) have been expanded to 12 subclasses, 24 levels and 16 types. (8) Level non-deep simple epicotyl MPD with four types is added to the system. (9) Level deep simple regular epicotyl MPD is divided into four types. (10) Level deep simple double MPD is divided into two types. (11) Seeds with a water-impermeable seed coat in which the embryo-haustorium grows after germination (Canna) has been added to the class combinational dormancy. The hierarchical division of primary seed dormancy into many distinct categories highlights its great diversity and complexity at the whole-seed level, which can be expressed most accurately by dormancy formulae.

Original languageEnglish
Pages (from-to)249-277
Number of pages29
JournalSeed Science Research
Issue number4
StatePublished - Dec 1 2021

Bibliographical note

Publisher Copyright:
Copyright © The Author(s), 2021. Published by Cambridge University Press.


  • combinational dormancy
  • cryptogeal germination
  • double dormancy
  • epicotyl dormancy
  • morphophysiological dormancy
  • physical dormancy
  • physiological dormancy

ASJC Scopus subject areas

  • Plant Science


Dive into the research topics of 'The great diversity in kinds of seed dormancy: A revision of the Nikolaeva-Baskin classification system for primary seed dormancy'. Together they form a unique fingerprint.

Cite this