Drought resistance of plants in relation to hysteresis in sorption I Hydration and dehydration of the leaves of certain drought resistant and drought sensitive plants II Adaptability of the Ragi plant to varying conditions of soil drought
Rao, B.S.
Proceedings Nation Inst Science India: 41-49, 51-58, 7
1949
Document Number: 526349
The capillary structure of the leaf tissue plays an important role in determining the degree of drought resistance of plants as revealed by the study of balsam, paddy, ragi, wheat and oats. The leaves of these plants were subjected to successive hydration and dehydration in a quartz fiber spring balance. Hysteresis is exhibited in all the systems and the hysteresis loop disappeared after a certain number of hydrations and dehydrations. These indicate that the capillaries in the leaf tissue are of fairly rigid walls. At any particular relative humidity, balsam takes the least and oats the most water. The 6 plants can be arranged in the increasing order of drought resistance as follows: Balsam, paddy, ragi, wheat and oats. The leaves of ragi plants cultivated in soils of varying droughts-65%, 47%, 40% and 36.5% moisture-were subjected to a series of hydrations and dehydrations. In all the 4 cases the hydration and dehydration isotherms and the hysteresis loops were nearly coincident. These indicate that the cavities and the open pores in the leaves of the 4 plants are nearly of the same size.