Seasonal biochemical changes in the living bark and needles of red pine (Pinus resinosa) in relation to adaptation to freezing

Abstract

Studies of physiological and biochemical changes associated with the seasonal cycle of frost hardiness in the living bark and needles of red pine (Pinus resinosa Ait.) indicate that seasonal changes in soluble protein (borate buffer) and in the rate of incorporation of radioactive leucine into protein are closely correlated with the changes in hardiness. The seasonal cycles of carbohydrates and amino acids do not appear to be closely related to hardiness in red pine. The results support the view that the development of hardiness in woody plants is associated with the augmentation of total cellular protoplasm.