EFFECTS OF SALT STRESS ON THE GROWTH, PHOTOSYNTHETIC PIGMENTS AND STRUCTURE OF TWO HALOPHYTES, IRIS HALOPHILA AND I. LACTEA VAR. CHINENSIS

摘要

Two species of Iris L., Iris halophila Pall and I. lac-tea var. chinensis (Fisch.) Koidz, are halophytes. The goal of this study was to disclose the salt tolerance mechanism of I. halophila and I. lactea var. chinensis. The results showed that the contents of chlorophyll and carotenoid of two species were not significantly changed under 1.5% NaCl stress, and the dry weights (DWs) of shoot and root were increased by 28 d treatment. Using tissue anatomy, we found that root cells epidermis and the inner cortical of I. lactea var. chinensis are thick and I. halophila has developed root aerenchyma which increased respiration of roots. Moreover, there were no obvious damage changes in the chloroplast morphology and subcellular structure of two species under salt treatment. The results indicated that I. halophila and I. lactea var. chinensis are promising halophytes for the improvement of saline land.