Photoperiodic control of seasonal growth is mediated by ABA acting on cell-cell communication
|标题：||Photoperiodic control of seasonal growth is mediated by ABA acting on cell-cell communication|
In temperate and boreal ecosystems, seasonal cycles of growth and dormancy allow perennial plants to adapt to winter conditions. We show, in hybrid aspen trees, that photoperiodic regulation of dormancy is mechanistically distinct from autumnal growth cessation. Dormancy sets in when symplastic inter-cellular communication through plasmodesmata is blocked by a process dependent upon the phytohormone abscisic acid (ABA). The communication blockage prevents growth-promoting signals from accessing the meristem. Thus, precocious growth is disallowed during dormancy. The dormant period, which supports robust survival of the aspen tree in winter, is due to loss of access to growth promoting signals.