Growth Analysis of No-Tillage and Conventional Tillage Rice Plants

Abstract

To clarify the growth of rice plants grown under no-tillage and conventional tillage conditions, N absorption pattern and tillering habit at the early growth stage, and N absorption, photosynthetic and exudation rate of rice plants at the middle and late growth stages were examined. Results obtained were as follows ; 1) There was no difference in the number of tillers between no-tillage (NT) and conventional tillage (CT) grown rice within 3 weeks after transplanting. However, the increasing rate of tillers in CT was more than that in NT. No significant difference was observed in basal N absorption by rice plants between NT and CY from transplanting to the middle of June. In the NT plants, the amount of basal N at the end of June was almost same as that at the middle of June. On the other hand, in CT plants, the amount of basal N at the end of June was two times higher than at the middle of June.2) The relationship between soil hardness, plant shoots and root dry weight was presented by linear equations. Increasing soil hardness caused a decrease in the dry weight and amount of N in the rice plant. 3) The rate of N absorption and exudation by rice plants under NT conditions was more than that under CT conditions at the middle and late growth stages. In addition, the photosynthetic rate of rice plants under NT conditions at the late growth stage was more than that under CT conditions.