MORPHOLOGICAL-STUDIES ON THE REGULARITY OF SHOOTS DEVELOPMENT IN RICE PLANTS .4. STRUCTURAL REGULARITY IN THE GROWTH TYPES OF TILLERS AND THEIR MOTHER SHOOTS

It has already shown that the main shoots of two different growth types coexist even in a precisely cultured plot. These types are : (i) N type with n leaves, (ii) N-1 type with n-1 leaves ; these types may be identified by the pattern of the length of leaves and elongated internodes, that successively develop on the main stem. In this paper, I present a comparative analysis of the growth types of tillers and their mother shoots. 1) When the number of leaves on tiller (including propyll, expressed as NLT) is equal to that of leaves in the nodes above the mother node which subtend the tiller in question (expressed as NLM), the growth type of the tiller is identical to the mother shoot. There are generally two patterns in this case : both tiller and its mother shoot represent N-1 type or N-2 type. 2) When NLT is one less than NLM, the mother shoot represents N-1 type and the tiller represents N-2 type. However, the lower primary tillers represent N-1 type on the main shoot of N type. 3) On the main shoot of N type, the upper primary tillers represent N-2 type. 4) It is considered that the growth types, as in case 1), are fundamental ones. The growth patterns in case 1), namely mother shoot-replica-tiller growth pattern shall be designated as ''replicative tiller-growth''.