Tillering behavior in Oryza sativa L. II. The tillering pattern as affected by the balance in the growth rate between the main stem and tillers.

Abstract

Tillering behavior of rice plants (1 plant/pot) of three cultivars was investigated. In a rice plant, there are differences (D) in growth speed between the main stem and each tiller. In the previous paper, we prescribed a relative tiller age (RA) to the individual tillers, and compared the ages of every tiller with each other. In this paper, we investigated the relationship between D and the increasing pattern of tiller number. If there is no D, we can make a curve called a synchronous growth curve indicating the increasing pattern of tiller number when leaves of each tiller and leaves of the main stem expanded synchronously (synchronous growth). Using three cultivars, we analyzed the pattern of synchronous growth curves and discussed the differences in the tiller behavior among the cultivars. We simulated the synchronous growth curve when every tiller appears in a rice plant. Assuming the value of D, we also simulated the growth curve when every tiller appears. Compared the curve with the synchronous growth curve, we discussed the relationship between D and the increasing pattern of ti1ler number.