Dynamic effect of NaCl on absorption and transportation of K~+and Na~+ in Festuca arundinacea
LI Pin-fang,YANG Zhi-cheng(College of Resources and Environmental Sciences ,China Agricultural University ,Beijing 100094 ,China)
This study ai med to elucidate the effects of salinity on the growth of tall Fescue (Festuca arundina-cea) . Seedlings were cultured for 5 weeks under hydroponic conditions with nutrient solutions containing 0(CK) ,50 ,100 ,150 ,200 ,250 ,300 and,350 mmol/L NaCl . At several intervals over the study period the tillernumber ,dry matter and, K+and Na+content in top and root , were determined. Results showed that the tillernumber ,dry matter weight , K+content , K+/Na+and the transport selectivity of K+(SK+/Na+-transport) de-clined under high NaCl concentration, while Na+content wasincreasedin both shoots and roots .It was shownthat the depressive effect of NaCl stress on growth was more pronouncedin shoots thanin roots . The absorp-tion selectivity of K+was reduced mainly by NaCl concentrationin the nutrient solution. The transport selec-tivity of K+and Na+decreased significantly as the treat ment duration progressed.