Effects of some respiratory inhibitors on water flux in root hairs of Avena sativa

Abstract

Effects of potassium cyanide, sodium azide, and sodium fluoride on water uptake by root hairs of Avena sativa have been investigated. Low concentrations (2 × 10−6 and 2 × 10−5 M) of potassium cyanide accelerate the velocity of water uptake; a decline in the magnitude of water uptake is observed at 2 × 10−4 M and 55% inhibition at 2 × 10−3 M.Azide and fluoride, on the other hand, convert excretion into absorption when applied at low concentrations (3 × 10−4 M and 6 × 10−6 M, respectively) while at increased inhibiting concentrations absorption may be converted into excretion without causing the death of the root hairs.The evidence presented strongly suggests an intimate relationship between respiratory metabolism and absorption of water.