7Monica N. Exogenous salicylic acid increases polyamine content but may decrease drought tolerance in maize[J]. Plant Sci. ,2002,162:569-574.
8Hafid E R, Smith D H, Karrou M,et al. Physiological responses of spring durum wheat cultivars to early-season drought in a Mediter-ranean environment[J]. Annals of Botany, 1998,81 (2):363-370.
10Lrigoyen J J,Emerich D W. Water stress induced changes in concen-tration of praline and total soluble sugars in modulates alfalfa(Med-icagosatire) plants[J]. Physiologic Planetarium, 1992,84:55-60.
