Growth and Development of the Wheat Tiller. I. Growth and Form of the Tiller Bud

The initiation and growth of the tiller bud is described in the context of the developing shoot in wheat. The experimental plants were subjected to two levels of nitrogen supply and to two light intensities so as to diversify the pattern of tiller growth. The descriptions cover properties of tiller bud placement within the shoot, the external developmental morphology, and some aspects of the developmental anatomy of the bud, and of the nodal plexus in relation to growth of the leaf primordium and tiller bud. The results have been integrated in terms of linear relative growth rates in both radial and axial directions. In spite of the mutual constraints imposed within the continuous system, severe gradients in axial growth rates were found to be consistent with the maintenance of the integrity of the system.