Study on the growth and characteristics of mineral nutrition and ion absorption of pomelo seedlings under salt stress

The growth and characteristics of mineral nutrition and ion absorption of pomelo (Citrus grandis Osbeck cv. Pingshanyou) seedlings were studied under various salinity levels. The results showed that the plant height, leaf area, shoot and root dry weight decreased drastically with the increase in the concentration of 80～200(mmol/L) NaCl salinity after sand culture for 30days. Solution culture for 8 days, the contents of Na+ and Cl- in root and shoot of pingshanyou seedlings increased with the salt concentration increased, but the contents of K2+,Ca2+,Mg+ and P, Mn decreased, the contents of Fe,Zn and Cu depended on organ. The Fe content in shoot was sensitive to salt stress, it could be used as an important index for evaluating the salt tolerance of pomelo seedlings. The value of K+/Na+,Ca2+/Na+ and Mg2+/Na+ in shoot of seedlings decreased obviously when the salt concentration was 40(mmol/L), the value of Mg2+/Na++/Na+>1 when salt concentration lower than 120(mmol/L) and K+/Na++ was higher than that of Cl- under various salinity levels.