Changes in the Number of Flower Buds and its Development of Oil Seed Rape

Abstract

Because high yield of oil seed rape is generally attained by increasing number or pods, changes in the number of flower buds differentiated, and their development into flowers and pods according to the growth stages were investigated. Results obtained are as follows: 1. Greater part of flower buds in the plant were differentiated on the secondary branches. The ratio of the number of flower buds on the main stem, primary, secondary and tertiary branches to the all buds were 1.5, 25.0, 63.0 and 10.5%, respectively. 2. Greater part of flowers were also developed on the secondary branches. The ratio of the number of flowers to total flowers on the main stem, primary and secondary branches were 34.7, 58.6 and 6.7%, respectively. All of flower buds on the tertiary branches failed to bloom. 3. The ratio of the number of flowers to flower buds differentiated on the main stem differed considerably with those on branches, the ratio on the main stem, primary and secondary branches being 75.9, 40.8 and 9.6%, respectively. 4. On the main stem and primary branches, almost all flower buds in which ovule protuberances became visible on the inner wall of pistil just before flowering stage of the plant, developed into flowers. On the secondary branches, however, the rate of developing to flowers was only 58.0%. 5. Greater part of pods in the plant were produced on the primary branches. The ratio of the number of pods on the main stem, primary and secondary branches to total pods were 12.9, 76.9 and 10.9%, rcspectively. 6. On the main stem and primary branches, greater part of flowers developed into pods. The rate of the number of pods to number of flowers on the main stem and primary branches were 76.0 and 61.0%, respectivcly. But, on the secondary branches, the rate was only 16.3%.