抄録
Physiological activities of hulls of unclosed and wounded spikelets were compared with those of normal one during ripening. The results are as follows : 1. In the checking at early and middle stage of ripening, fresh weight, percentage of water content and chlorophyll content were lower in hulls of unclosed and wounded spikelets than in those of normal one. And respiratory and photosynthetic activities were also lower in these. 2. Increase in dry weight of hulls and kernels was lower in these spikelets, of which physiological activity declined. 3. There was a negative correlation between degree of damage on spikelets by Typhoon and dry weights of hull and kernel. From these results, it was demonstrated that decline in physiological activity of hull of spikelet cause to decline in sink activity, i.e., pumping up carbohydrates from leaf and stem.