Mechanisms underlying the effects of fall dormancy on the cold acclimation and winter hard-iness of Medicago sativa
As a global planting forage legume, alfalfa (Medicago sativa) is a valuable material to study the evolutionary and ecological mechanisms on plant adaptation to freezing due to their contrasting winter hardiness induced by fall dormancy (FD). This paper reveals that FD is an important growth characteristic that is adaptative to short-day and reducing temperature in late autumn, followed by a higher overwintering rate. Alfalfa cultivars are grouped into 11 FD ratings (numbered from 1 to 11), and this phenomenon is related to the extensive spread and cultiva-tion for thousands of years in the globe. Alfalfa cultivars are under different climate habitats for a long time, lead-ing to FD adaptive evolution, which provides rich genetic resources for human. In general, adaptative process as-sociated with cold acclimation and winter hardiness in alfalfa is affected by FD, thus differences in winter hardi-ness exist among alfalfa cultivars. So far, regulation of FD by light and temperature and effects of FD on physio-logical and ecological processes involved in cold acclimation have been reported largely. However, signal trans-duction and the regulatory network associated with gene expression, especially the molecular mechanisms by which antifreeze proteins function in cold adaptation, are still poorly understood. Several scientific problems that need to be addressed in the future studies are highlighted in this review.
fall dormancywinter hardinesscold acclimationoverwintering rateMedicago sativa
NETL
NSTL
万方数据
维普
