DETERMINATE GROWTH IN THE BLUEBERRY

Abstract

Elongation of the vegetative branch of the blueberry ceases early in June owing to the death of both the apical meristem and the distal portion of the axis. Coincident with this is the development of a flowering branch primordium in the axil of the penultimate leaf. During July, the apical meristem of the flowering branch becomes inactive. It is either laterally displaced or it elongates as a minute unbranched columnar structure. Coincident with this inactivation, the proximal flower primordia develop florets in which all flower parts may be recognized, but the distal flower primordia, that is those adjacent to the inactivated apical meristem, are retarded in their development. The retarded distal flower primordia are developed in acropetal succession but the proximal flower primordia do not exhibit acropetal succession. All the stages are illustrated by line diagrams.