Seed dormancy and germination of the subalpine geophyte Crocus alatavicus (Iridaceae)

Abstract

Crocus alatavicus Regel et Sem. is a cormous perennial primarily distributed in central Asia that may have potential in horticulture; however, relatively little is known about seed dormancy in the genus Crocus. The primary aim of the present study was to identify the dormancy breaking and germination requirements of seeds of C. alatvicus and to assign them to a dormancy category. In its natural habitat, the underdeveloped embryo in C. alatavicus seeds grows in early summer, and radicles emerge in early autumn. However, cotyledon emergence is delayed until the following spring. Radicle emergence was promoted by warm stratification and cotyledon emergence by cold stratification. GA3 was ineffective in promoting either radicle or epicotyl emergence. We conclude that seeds of C. alatavicus have deep simple epicotyl morphophysiological dormancy of the type C1bB(root) – C3(shoot). To our knowledge, this is the first detailed study on the ecophysiology of seed dormancy and germination in the genus Crocus.