作物の塩水被害葉におけるNa,Cl(2)

Although the excessive absorption of sodium and chloride ion appears to be related to any inhibition in growth or function, the levels of these contents at which symptoms develop are not too well defined and the causal relationship of ion accumulation to saline injury is still in the stage of mere presumption. In this paper, we attempted to make clear more precisely the behaviour of these ions associated with a specific burn symptom.
The distributions of sodium and chloride ions in a leaf blade were given in Fig.1 and Fig. 2. The increase of the contents in developmental process of symptom was shown, while rhe contents were inversely decreasing in dead part distinguished as a visible symptom. The same phenomenon was also found in the case of potassium content (Fig. 1-2), but phosphorus content was resulted to have no relation with symptom (Fig.1-3). However, as teported before, the levels of Na and Cl contents related to injury cnanged with ecological factors, viz. different leaf-orders and different concentrations of saline solution, and indeed, uninjured part on a leaf in lower leaf-order or in same leaf-order on plant treated by saline solution with higher concentratlon might sometimes have higher content than injured part in higher or same leaf-order under lower concentration.
Cl/Na ratio-Cooper et. al. used for salt-sensitive species in cltrus-changed also with ecological factors, but this value was connected closely with injury(Fig. 3).
Cl/(Na＋K) ratio related to injury was nearly equal at the same degree of symptom under two conditions (Fig.4-1, 4-2, 4-3). Therefore, it seems that this value might be useful to standardize contents indindualized by ecological factors and to make clear the mechnism of saline injury caused by ions toxicity.