EFFECT OF VARIOUS METHODS OF STORAGE ON THE CHLOROPHYLL CONTENT OF LEAVES

Abstract

Problems involving the quantitative determination of the chlorophyll content of leaves have been carried out chiefly with plants grown in a greenhouse or in the immediate vicinity of a laboratory. This allows the extraction of the chloroplast pigments within a few minutes after the samples are secured and, as the chlorophyll content of the leaves is practically unaltered, the results may be taken to represent the conditions existing in the living tissue. A recent investigation by Deuber (1) shows a wide variation in the chlorophyll content of the leaves of different species, of trees. The chlorophyll determinations were all made from fresh leaves, gathered from trees growing near the laboratory. It would be desirable to have similar information regarding the leaves of trees growing in other localities where environmental conditions are different. The investigation of Sprague and Shive (9) on the relations between chloroplast pigments and the dry weights of tops in dent corn and the work of Guthrie (3) on the effect of environmental conditions on the chloroplast pigments suggest interesting and instructive problems that might be carried out with plants growing in widely separated habitats. In such cases the extraction and determination of the pigments must be made from stored or preserved leaves. As the question of storage of green tissues for later determination of chloroplast pigments has received only slight attention, it is the purpose of the present investigation to determine the effect of various methods of storage on the chlorophyll content of leaves. Procedure