biologia plantarum

Biologia plantarum 15:194-201, 1973 | DOI: 10.1007/BF02922393

Plant nitrogen metabolism and calcium or potassium Deficiency

Svatava Fialová¹, I. Pichl¹

¹ Department of Plant Physiology and Soil Biology, Faculty of Science, Charles University, Praha 2, Czechoslovakia

The content and distribution of nitrogen substances in wheat, pumpkin and pea seedlings in complete (NS) or deficient ( - Ca²⁺ or - K⁺) nutrient solutions were studied with the aim of establishing whether impairments in the synthesis of nitrogen substances in vegetative tissues due to the deficiencies may be compensated for by storage nitrogenous substances. Pumpkin and pea seedlings were found to accumulate nitrogen mainly from depots of the seed stores. Both the accumulation and the synthesis of nitrogen substances were inhibited by the cation deficiencies, especially by that of calcium. Concomitant morphological deformations were probably the direct cause of the impairments in the mobilization and hence also in the utilization of the substances. With wheat, on the other hand, no morphological changes resulted from the deficiences and nitrogen was accumulated intensively even from the cultivation solution. Still, the rate of the synthesis of the nitrogenous substances was significantly reduced. Under the conditions of calcium or potassium deficiency in the outer nutrient solution the possibility or utilizing the ions from the storage tissues according to the requirements of the plant appeared to be decisive. The extent of the disproportion of the two factors was the original cause of the early morphological changes which, in their turn, impaired the natural circulation of substancs inside the organism, including the substances containing nitrogen.

Received: February 25, 1972; Published: May 1, 1973  Show citation