Plant Physiol, April 2002, Vol. 128, pp. 1439-1446
Molecular Analysis of Signals Controlling Dormancy and Growth
in Underground Adventitious Buds of Leafy Spurge
David P.
Horvath,*
Wun S.
Chao, and
James V.
Anderson
United States Department of Agriculture, Agricultural Research
Service, Biosciences Research Laboratory, P.O. Box 5674, State
University Station, Fargo, North Dakota 58105-5674
Dormancy and subsequent regrowth of adventitious buds is a critical
physiological process for many perennial plants. We have used the
expression of hormone and cell cycle-responsive genes as markers to
follow this process in leafy spurge (Euphorbia esula). In conjunction with earlier studies, we show that loss of mature leaves
results in decreased sugar levels and increased gibberellin perception
in underground adventitious buds. Gibberellin is sufficient for
induction of S phase-specific but not M phase-specific gene expression.
Loss of both apical and axillary buds or inhibition of polar auxin
transport did not result in induction of S phase- or M phase-specific
gene expression. Loss of polar auxin transport was necessary for
continuation of the cell cycle and further bud development if the S
phase was previously initiated.
*
Corresponding author; e-mail horvathd{at}fargo.ars.usda.gov;
fax 701-239-1252.
© 2002 American Society of Plant Physiologists
