Studies On Drought Resistance And Salt Resistance In Iris L.

Studies On Drought resistance and Salt resistance in Iris L.Iris germanica 8# ( 'white and blue ') and Iris tectorum (one-year old seedlings) have been used for this research. The studies contained two parts. Part I . water stress and drought resistance, part II. salt stress and salinity resistance.Part I. Water stress and drought resistanceIris germanica 8# and /. tectorum were treated with different concentration of osmotic stress solutions (PEG 6000) 5%, 10%, 20% and 30%. The determination had been done after the treatment on 6 days and 12 days. The results showed that the relative permeability of plasma membrane of /. germanica 8# was lower than 7. tectorum, the activity of SOD and osmotic adjustment substances proline and soluble protein contents of /. germanica 8# were much higher than 7. tectorum. There was an obvious inverse correlation between SOD activity and MDA content on 12 days treatment.This research confirms that 7. germanica 8# has higher ability for drought resistance. The lower permeability and the lower MDA content, the higher SOD activity, the higher proline and soluble protein content are five important physiological properties for drought resistance in Iris L.Part II. Salt stress and salinity resistance7. germanica 8# and 7. tectorum were treated with different concentration of NaCl solutions: 0.3%, 0.6% and 0.9%. The determination had been done after the treatment on 4 days and 8 days. The results showed that the relative permeability of plasma membrane and the MDA content of 7. germanica 8# were lower than 7. tectorum. The SOD activity and proline content of 7. germanica 8# were much higher than 7. tectorum.This research confirms that 7. germanica 8# has higher ability for salt resistance. The lower permeability and the lower MDA content, the higher SOD activity and the higher proline content are four important physiological properties for salt resistance in 7m L.