Factors associated with determination of root ²²Na (+) influx in the salt accumulation halophyte Suaeda maritima.
Salinity is an increasing problem for agricultural production worldwide. The result of low-affinity Na(+) uptake is toxic to the cytoplasm of most crop plants. Nevertheless, the pathways for this low-affinity Na(+) uptake are still uncertain. In this work we used ²²Na(+) isotope tracing technology to investigate factors associated with determination of root ²²Na(+) influx in the salt accumulation halophyte Suaeda maritima. We found that a 2 min of exposure to the ²²Na(+) labeled uptake solution was optimal for determining ²²Na(+) influx into excised roots of S. maritima and that 7 min of blotting is suitable in ²²Na(+) influx experiments. ²²Na(+) influx did not increase linearly with the increasing external Na(+) concentration, in the range tested, of 2 to 300 mM NaCl. But root ²²Na(+) influx and root Na(+) concentration were well correlated. ²²Na(+) influx into excised roots of S. maritima was not, however, well correlated with the plant size. All the above results indicated further that this ²²Na(+) isotope influx procedure is a good method for quantify Na(+) uptake rate by the roots of the salt accumulation halophyte.
Zhang
Jin-Lin
JL
College of Pastoral Agriculture Science and Technology, Key Laboratory of Grassland Agro-ecosystem, Ministry of Agriculture, Lanzhou University, P.O. Box 61, Lanzhou 730000, China.
Wetson
Anne M
AM
Wang
Suo-Min
SM
Gurmani
Ali R
AR
Bao
Ai-Ke
AK
Wang
Chun-Mei
CM
D019663:Chenopodiaceae / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism*; D055051:Salt-Tolerant Plants / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*
D012964:Sodium