Effect of Atmospheric Fluoride on Respiration of Bush Beans

Abstract

1. The oxygen uptake in bush-bean plants is accelerated when the plants are exposed to atmospheric fluoride at concentration levels below those inducing visible foliar symptoms of fluorosis. 2. Under the environmental conditions used in this experiment, fluoride uptake of bean plants given a 24-hour fumigation just prior to the day of sampling was relatively constant from the eighth to the twentieth days of growth. Similar plants fumigated continuously from planting until harvest showed steadily increasing amounts of tissue fluoride because of the greater duration of exposure. Under the 24-hour fumigation the daily rate of fluoride accumulation tended to increase until after the plants had emerged and then remained relatively constant; under continuous fumigation the rate tended to increase throughout.