Drought Hardening of Crop Plants

摘要

The relation between drought hardiness and osmoregulation in Pisum sativum (pea) was studied by using pressure volume curve technique with the Richter diagram (relative water content vs. inverse leaf water potential). Two additional water relation parameters (bulk elastic modulus of the leaf and structure coefficient) can be derived from this diagram which could not be obtained from the usual pressure volume curves. Turgor pressure at water saturation and the leaf water potential at turgor loss point are obtained by regression analysis for the individual leaves. Their values for control and drought hardened plants are used to detect osmoregulation. Lower osmotic potentials after removal of water stress indicates osmoregulation. Ten days of water stress during early stages of development followed by rewatering during a prolonged period resulted in decreased osmotic potential, that is higher drought resistance.