Studies on matter production of rape plants. VI. The effect of dry matter production during the period from the beginning of flowering to maturity on the number of pods in a plant.

Abstract

The present work is an attempt to evaluate the effect of dry matter production during the period from the beginning of flowering to maturity on the number of pods in a rape plant (Brassica napus L.) cv. Norin No. 16 grown in a field. The amount of dry matter production were changed by leaf cutting (at the beginning of flowering) and shading (from the beginning of flowering to maturity). The following results were obtained : 1. The number of pods per plant increased with the increment of total dry weight per plant during the period from the beginning of flowering to maturity (Fig. 1). 2. The increment of number of pods per plant depended mainly on those of the number of inflorescences of secondary branches and of the number of pods per inflorescence of each kind of branch (Figs. 2 and 4). 3. The number of inflorescences of secondary branches in each primary branch increased with the increment of total dry weight per plant (Fig. 3). 4. In each node order, the number of pods per inflorescence attached to primary or secondary branches increased with the increment of total dry weight per plant (Fig. 5 and Table 2). 5. The pods formed by dry matter production during the period from the beginning of flowering to maturity were estimated to be about 75% of the total number of pods per plant and 50% of the total number of pods per inflorescence (Figs. 1 and 4).