This greenhouse experiment was conducted to evaluate the soil oxygen effects on concentrations and total amounts of nutrients in citrus seedlings (Citrus sinensis Osbeck) and in the soil medium in which the plants were grown.
Reduction in amount of soil oxygen to the roots significantly decreased N, P, K, Ca, Mg, Zn, Cu, Mn, B, and Fe concentrations in the leaves, and increased these elements in the roots. A significant increase in concentration of Na, Cl, and N, and a decrease of K, Ca, and Mg in the stems was caused by the low level soil oxygen.
Total amounts of P, K, Ca, Mg, Cl, Zn, Cu, Mn, and B per whole plant were significantly lower when grown under the low soil oxygen supply. Soils supplied with low levels of soil oxygen contained higher concentrations of NO3-N and Ca than soils treated with the normal level of soil oxygen.
Low level soil oxygen resulted in an increase in Na and Cl concentrations in the stems only, and not, as had been previously assumed, in the leaves.
Soil oxygen effects on the uptake and translocation of nutrients in plants cannot be assessed solely on the basis of the nutrient concentrations in the plant leaves. Consideration of plant dry weight and total mineral content per plant are essentials in studying the experimental relationship of soil oxygen to the plant nutritional status.