Cation-anion relationships in crop nutrition: III. Relationships between the ratios of sum of the cations: sum of the anions and nitrogen concentrations in several plant species

The ratios of sum of the cations: sum of the anions (R) of sixty-two agricultural and horticultural crops and pasture herbs were measured or calculated and found to be negatively correlated with % N in the plants. This suggests that the proposal that Italian rye-grass has a mechanism regulating the proportion of cations to anions taken up may also apply to other plant species. Dicotyledons had greater B values than monocotyledons at the same N level, but this is probably not because their roots have greater cation exchange capacity.