作物の塩害に関する研究(V) : 水稲被害葉の塩分集積量及び水分含量について

Determinations of sodium, chloride and leaf-moisture content were made on leaves of rice plant grown on a series of artificially salinized plots. The decrease of moisture content in leaves affected was circumstanced proportionally with the progress of leaf-burn symptoms and even in a leaf where the burn symptom began to develop, the moisture content in the green portion was the same with that of an uninjured leaf (a normal leaf). And the severity of the tip burn was closely associated with the levels of sodium and chloride accumulation, but unlike the case of the moisture described above, the relationship between the accumulation and the severity was not linear and the uniniured portion of a burned leaf had higher chloride accumulation than an uninjured leaf and also it was found that the accumulation was higher on the older leaves for similar severity. Moreover, the equivalent relation between sodium and chloride accumulation in a leaf would indicate that sodium and chloride added to the base nutrient solution were carried in mass flow process.
Accordingly, it seems that the saline effect on the plant is attributed to the presence of abnormally high amount of sodium or chloride in leaves rather than the inhibition of water-availability in the whole plant.