Plant dormancy and dormancy breaking depend, at least partially, on peculia
r short distance relationships between buds and tissues underlying buds (bu
d stands), In peach-tree, it was previously observed that dormancy was rela
ted to a high nutrient absorption capacity in tissues underlying buds, This
situation could be linked to higher plasma membrane ATPase activity (EC 3.
6.1.3), inducing a higher nutrient absorption, in bud stands, This work con
sists of characterization of the plasma membrane ATPase activity in vegetat
ive buds and bud stands during the rest period and dormancy release. During
the dormant period (October and November), plasma membrane ATPase activity
was found to be higher in bud stands than in buds, This was correlated wit
h a lower amount of plasma membrane ATPase in buds compared to bud stands d
uring this period, Moreover, plasma membrane ATPase activation by trypsin t
reatment was not the same in both tissues and different levels of ATPase ac
tivation could be noted within the same tissue during the different stages
of dormancy release, According to these results, it can be postulated that
dormancy release in peach-tree, is related to modifications of plasma membr
ane ATPase properties in buds and bud stands during winter time,