Apparatus for Infiltration of Liquids into Leaves

Abstract

VACUUM infiltration of liquids into leaves is a technique that has been used for many years. So far as I am aware, the usual procedure is to keep the leaf under liquid while reducing the pressure. Air bubbles then escape from the stomata, and any adhering when the lowest pressure has been attained are dislodged, often with difficulty, by shaking the container; for when the vacuum is afterwards released the adherence of these bubbles would spoil the efficiency of infiltration. The difficulty of bubble removal is greatly increased when a number of leaves are simultaneously infiltrated, so that it is desirable to use as few leaves as possible, or even to treat them singly. To overcome such difficulties it is best to reduce the pressure while the leaves are in air, releasing pressure only after putting the leaves under liquid. A convenient way of doing this is described below.