Ionic balance and growth of carnations
Green, James L. (James Lon), author
A flow chart for diagnosing the nutrient status of carnation, Dianthus caryophyllus, was designed using the data from nutrient culture experiments. Diagnostic values for any specific ion were determined after considering the overall organic acid content, (C-A), of the plant and the level of the other ions in the plant tissue. The optimum (C-A) content for the carnation was 1700-1900 milligram equivalents per kilogram dry matter. There was a highly significant correlation between increase in (C-A) content and plant yield. Changes in the (C-A) content with few exceptions were mainly due to changes in the cation (C) concentration of the plant tissue. External factors affected the (C-A) content. Two levels of the external factors, light and CO2, were studied. There was a significant increase in chloride uptake at the higher light level. The total cation, magnesium, nitrate, and (C-A) concentrations in the tissue were significantly increased at the higher CO2 level. Total cation uptake, total (C-A), and yield were increased at the higher CO2 level. There was a decrease in chloride uptake at the higher CO2 level. There were probably three systems operating in cation uptake. 1. When potassium was in, good supply, its presence suppressed the uptake of sodium rather effectively. 2. When the potassium supply was deficient, the four ions K, Nat Ca, and Mg competed for uptake. 3. Magnesium and calcium may have been taken up by a separate system in which they competed equally for uptake. Sodium enhanced the uptake of the other cations. There was no apparent competition among anions for uptake. Sulfate and nitrate remained fairly constant in the plant tissue regardless of nutrient treatment. Phosphate was readily taken up, probably in luxury quantities. The chloride ion apparently was taken up over and above the normal inorganic anion uptake.
Includes bibliographical references (pages -78).