ATP AND GROWTH IN FLUORIDE-TREATED PEA SHOOTS

Shoots of 17-day-old peas were placed in solutions of 1 mM KF, 1 mM KCl or water in light or darkness. F--induced increases in ATP levels were detected in the youngest, fully expanded pair of leaves, and in entire shoots, after 24 h of treatment. ATP levels also increased in the dark in F--treated pea shoots after 24 h. These increases occurred before F--induced decreases in fresh weight, water content or water uptake. F--induced decreases in stem elongation were detected after 24 h. Decreasing growth by treatment with 0.5 mM B-9 (succinic acid-2,2-dimethyl hydrazide) or by removing terminal buds had little effect on ATP levels. Reducing uptake of water by treatment with 10 .mu.M abscisic acid also had little effect on ATP levels.