XVI International Botanical Congess
Electrical activities in shoots of Crassula portulacea were recorded from surface of five shoots for 90 days, successively, and auto-correlation, cross-correlation, and Fourier components were calculated. All potentials revealed daily rhythm with about 24 h periods. Cross-correlation between two potentials from two recording sites on a shoot was similar to auto-correlation, which guaranteed one site was enough to represent the electrical activity. Phase of maximum correlation between two branches did not show any shift from that of the stem for a week or so, then, abrupt phase-shift occurred and maintained for two month at least. Occasionally, cross-correlation between stem and branch seemed to diminish, but during these period correlation between branches were maintained. The results suggest functionally independent activities among shoots.