Studies on the Tiller Primordium and Tiller Bud in Rice Seedlings : XII. On the differentiation and growth process of the tiller primordium and tiller bud

Abstract

An anatomical study was carried out on the differentiation and growth process of the tiller primordium and tiller bud in rice seedlings. The differentiation of the tiller primordium in rice seedlings is due to the repeated periclinal divisions of the initial cell which is placed in the inner side of the dermatogen cells at the base of shoot apex on the main stem (Fig. 1, 2), and before the base of the leaf margin of a leaf primordium grows as far as the opposite side of the shoot apex, the tiller primordium appears at the base of the shoot apex (Fig. 3, 4). And after that the base of the leaf margin develops surrounding the upper part of the tiller primordium (Fig. 1C, 3, 5 and 7A). The tiller primordium differentiates firstly a prophyll, and then the first leaf primordium in tiller bud appears at the position of 90 degrees opposite to the prophyll, and it forms itself into a complete tiller bud. The second leaf primordium in the tiller bud differentiates at 180 degrees opposite to the first leaf primordium, thereafter the leaf primordia of the tiller bud differentiate alternately (Fig. 6). Taken the leaf which emerges from the leaf sheath of the main stem as standard (N), the (N-1) node and the (N-3) node tiller bud differentiate the two leaf primordia in one leaf-emergence-period, and then the first leaf of the (N-3) node tiller bud appears out of the leaf sheath of the main stem (Fig. 7).