Relationship of the Organic Acids of Tobacco to the Inorganic Basic Constituents

THE INFLUENCE OF LIGHT, TEMPERATURE, AND SOME ENZYME POISONS UPON THE TOTAL ORGANIC ACID CONTENT OF LEAF TISSUE OF KALANCHOE DAIGREMONTIANA (HAMET AND PERRIER)

“…Similar responses have been observed by other workers with other plant materials (10,12,27,28,35). It is unlikely that the organic acid changes described above are the result solely of such a differential in ion accumulation from the nutrient solution since the same anions, e.g., azide and iodoacetate, can inhibit both the formation and breakdown of organic acids.…”

Potassium Deficiency and Excess in Guayule. Ii. Cation-Anion Balance in the Leaves

“…The altered ratio in the low potassium samples could be accounted for by greater amounts of calcium or magnesium, or smaller amounts of sulphur or phosphorus in organic combination. In tobacco leaves (22) it was similarly found that the ratio: excess cations/organic acids exceeded unity, yet the reaction of these tissues indicated the organic acids are not entirely combined. Although there was correlation between excess cations and organic acids in tobacco leaves, the ratio as in guayule leaves was altered with changing mineral contents of the samples.…”

“…In this respect guayule differs from the tobacco plant (22) and from eleven of the twelve species studied by PIERCE and APPLEMAN (21 (table II). Parallel with increasing pH was an increase in carbonate constituents of the sap (largely bicarbonate in this range of reaction).…”

“…A relationship between the total organic acids and the excess of cations over inorganic anions in tobacco leaves of different ages and base composition was shown by PUCHER, VICKERY, and WAKEMAN (22). PIERCE and APPLEMAN (21) grew several species of plants in the same nutrient medium and showed a general correlation between the excess of cations and the total organic acids.…”

Organic Acid Metabolism and Ion Absorption in Roots

“…Since roots may absorb cations and anions at unequal rates from single salt solutions, they must therefore have at their disposal mechanisms for maintaining cation-anion equivalency. In recent years, the role of organic acid metabolism in relation to the mainteilance of cation-anion balance have been investigated by Pucher, Vickery and Wakeman (15), Ulrich (17), Overstreet, Broyer, Isaacs and Delwiche (11), Pierce and Appleman (13), Burstrom (2), Cooil (5), and others.…”