13 April 2018
Vol 360, Issue 6385

About The Cover

Cover image expansion

COVER Trees such as this aspen (Populus tremuloides) protect their meristem and leaf primordia from low temperatures during winter by establishing dormancy in apical buds. Reduction in day length, heralding the advent of winter, induces dormancy. The molecular mechanism underlying photoperiodic control of tree dormancy has been revealed to involve plant hormone–mediated blockage of plasmodesmata, channels that connect neighboring cells. See page 212.
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