Determination of Cell Numbers in Dried Leaf Material

Abstract

THE method of maceration in chromic acid followed by counting, using a hæmocytometer, has been widely used in the estimation of cell numbers in fresh leaf material^1–3. A new method has been developed by means of which cell numbers can be estimated for leaf material which has been oven-dried. The method has the following advantages: direct estimates of cell number can be obtained using dried material from growth-analysis investigations without the necessity of providing separate plants for sampling; this may be especially advantageous for work in glasshouse or constant environment rooms where space is often limited, average cell dry-weight is obtainable directly without the use of a separate sample, and dried material can be stored indefinitely without deterioration and macerated when opportunity arises. The procedure using dried material takes somewhat longer and the estimate of cell number obtained is sometimes slightly lower than that using comparable fresh leaves.