Experiments were conducted in a greenhouse during both fall and spring to study the influence of soil oxygen conditions and soil temperatures on the amounts of macro- and micronutrients in sweet orange seedlings (Citrus sinensis var. Bessie).
The total amounts of 11 nutrients and Na were determined in the roots and tops of citrus seedlings. Slight soil temperature differences, close to the optimum (22.5C and 27.8C) did not affect the dry weight of plants and the amounts of nutrients in the plants. However, there was a greater percentage of total K, Cl, and B found in the tops of plants grown at the higher soil temperature than at the lower.
The amounts of N, P, K, Ca, Mg, Zn, Cu, Mn, B, and Fe decreased in the citrus seedlings with decreasing soil oxygen supply to the roots. The chloride and Na content decreased in the roots and increased in the tops with decreasing soil-oxygen supply to the roots of the seedlings.
Citrus seedlings grown during the fall months produced more dry weight of plants, and contained, in general, larger amounts of nutrients per plant, except Na and Cl, than seedlings grown during the spring months.