碱茅营养吸收对盐胁迫及渗透胁迫的反应

The Responses of Puccinellia tenuiflora to the Salinity and Osmotic Stress in Nutrient Absorption

在０．０～－１．５ＭＰａ渗透势范围内，盐分（ＮａＣｌ）及渗透（ＰＥＧ，６０００）胁迫对碱茅植株Ｎ、Ｐ、Ｋ百分含量无显著影响。但随渗透势降低，植株队Ｎ、Ｐ、Ｋ吸收量迅速降低。与等渗的ＰＥＧ溶液相比，ＮａＣｌ溶液中植株Ｎ、Ｐ、Ｋ吸收量分别高５～１５ｍｇ／盆，０．５～０．８ｍｇ／盆（－０．７～１．５ＭＰａ范围）及５～１５ｍｇ／盆。盐溶液对植株Ｎ、Ｐ、Ｋ吸收的影响主要是它降低了溶液的渗透势，其次是溶液中离子的作用。

The percentage content of N,P,K in Puccinellia tenuiflora is not significantly influencdby the salinityand osmotic stress in the range of0.0 to-1.5 MPa while the ahorptions of N, P and K rapidly lower asthe osmotic potential of culture solution with NaCl and PEG decreases.No difference is observed in thepercentage contents of N and K in the isoomotic NaCl and PEG solutions while the absorptions of N,P andK of shoots in NaCl solution are increased by 5～15 mg/pot,0.5～0. 8mg/pot and 5～15 mg/potrespectively as compared with those in the isosmotic PEG solution,The effect of salt solution on theabsorption of N,P and K is mainly caused by lowering osmotic potential of the solution.Moreover,thefunction of ions in the solution is also important.