Abstract:
The stage of dormancy development at which deciduous nursery
stock can be safely defoliated for harvest was investigated in red-osier
dogwood (Cornus stolonifera Michx.). This stage, previously called
"vegetative maturity," was found to correspond to the onset of winter
dormancy in red-osier dogwood. A reduction in ethylene production
by excised plant parts is associated with dormancy development, and
occurs prior to this stage. This reduction occurs synchronously
throughout the plant, though ethylene production by basipetal tissues
prior to the decrease was lower than that by more acropetal tissues.
The pattern of change in ethylene production by nodal tissue, which
included the axillary buds and about 5 mm of petiole, seemed to be
least affected by environmental growing conditions. The results
obtained warrant investigation of the relationship between ethylene
production and dormancy development in other-woody plants.
