1972 Volume 19 Issue 2 Pages 55-61
In order to find the factors concerning the accumulation of nitrate in tomato fruit, the influences of phosphate, potassium, calcium and magnesium fertilizers were investigated. Low levels of these fertilizers and three levels of phosphate and potassium in factorial combination were applied to Fire Ball variety in sand culture.
When tomato plants were grown with the low level of potassium, the nitrate content in the fruit was very low, and potassium contents in the fruit and leaves were of low level.
The influence of phosphate on the nitrate content was not clear. With lowering of each of calcium and magnesium levels, no significant influence was observed on the nitrate accumulation in the tomato fruit.
The nitrate content in the tomato fruit changed during ripening, and according to various fertilizer tests four types of change were observed from the breaker through the red ripe stages, remarkable decrease, slight decrease, no change, and slight increase.
