Occurrence of Putrescine in Potassium-deficient Barley

Abstract

THE identification of primary effects of potassium in plant cells has proved to be one of the most elusive problems in mineral nutrition. Many widespread physiological disturbances accompanying potassium deficiency are well known, especially in the fields of nitrogen and carbohydrate metabolism; but the immediate causes of the characteristic (yet variable) leaf symptoms and the premature death of foliage have been almost entirely a matter for speculation. This communication is intended to direct attention to the fact that in barley, at least, putrescine is produced and accumulated under certain conditions of potassium deficiency, and that some of the observed symptoms may well be directly attributable to its presence.