Introduction. The present study had as objectives to measure the palm
leaf divergence angle in the field, to determine the frequency of trees and offshoots
showing clockwise and counterclockwise phyllotaxis, to establish the relationship
between phyllotaxis of the mother tree and that of its offshoots, and, finally,
to determine the effect of the divergence angle value on production. Materials
and methods. The vegetal material was composed of four Moroccan cultivars of
Phœnix dactylifera L. Observations were conducted in the south of Morocco on
20 trees per cultivar and four offshoots per tree. The divergence angle was
measured on adult trees whereas phyllotaxic direction (clockwise or counterclockwise)
was noted for both offshoots and adult trees. Results and discussion. This study
showed that the phyllotaxic direction of the offshoots presents a clockwise or
counterclockwise phyllotaxis independently of the mother plant. The divergence angle
varied depending on the cultivar. This character is an interesting criterion, both for
the selection of the best adapted cultivars for the marginal date palm growing regions,
and for an optimal production.