The Physiological Basis of Adventitious Root Formation

by F.T. Davies, Jr., and H. T. Hartmann

Poor rooting limits the commercial production of potentially important clones of many woody plant species. Why is it that certain clones are difficult to root? And why haven’t we made more advances in rooting success? Despite very active research, the primary chemical stimulus(I) to dedifferentiation ( the most critical step of adventitious root formation) remains unknown.
This paper explores current research on developmental and physiological aspects of rooting. Adventitious root formation (ARF) is an organized developmental process involving discrete biochemical, physiological and histological events in the induction, initiation, development and elongation of root primordia. Genetic aspects of rooting such as the role of transcription and translation in “competent” cells to dedifferentiated and form root primordia need to be better understood.
Rejuvenation of tissue via tissue culture, hedging and heavy pruning, layering, etiolation, serial cutting propagation, serial grafting, etc., have had some success on phase change in plants and their subsequent rooting potential. Physiological factors in perseverance conditioning in the selection of cutting material from stockplants are considered.

Acta Horticulturae 227, 1988, Vegetative Propagation Woody Species