THE TECHNIQUE OF "THE RELATIVE WATER CONTENT (CRA)" IN Crambe abyssinica, Hochst

Abstract

The relative water content (RWC) technique was examined to determine its suitability when leaf discs of Crambe abyssinica (Hochst) are used. Four experiments were conducted to investigate the relationships between levels of water stress (soil water
potential), leaf age, and stages of development of crambe plants. The evaluation of this technique involved three aspects: rehydration time of samples, changes in leaf discs dry weight during the flotation period, and the RWC estímate by itself.

lt was found that leaf discs of crambe completed the phase of rehydration in four hours at the different levels of water stress, stages of development and leaf ages. A statistical procedure to study the rehydration kinetics is also described. Non significant differences in dry weight were observed among leaf discs due to the flotation period, under the experimental conditions used. Finally, it was concluded that the RWC technique is suitable for studying water relations in crambe.