抄録
The carbon dioxide exchanges of the artificial communities of rape planted in pots were measured at both the beginning of flowering and the middle stage of ripening. The photosynthetic system of plant was mainly consisted of leaves at the beginning of flowering, and of pods at the middle stage of ripening. Using the data obtaincd, we compared gross photosynthesis at both stages and examined the relationship between PAI (pod area index) and the balance in matter production of pods at the middle stage of pod development. 1. The initial slope of photosynthesis-light curve of leaves rose with increasing LAI, whereas that of pods remained constant at all PAI's. The saturating light intensity of leaves was constant at all LAI's, whereas that of pods rose with increasing PAI. 2. Net production per day at the middle stage of ripening reached its maximum value at PAI 4, without declining at PAI 6 which is nearly the maximum value attainable in actual cultivation.
