Próba wyjaśnienia odmiennej reakcji roślin rzepaku i kukurydzy na azot stosowany w formie amonowej lub azotanowej [The attempt to explain the various reaktions of rape and corn plants on the nitrogen used in the ammonium or nitrate forms]

Abstract

The reaction of the rape and corn plants on the nitrogen applied in the form NO₃^- or NH₄⁺ was studied under the controlled conditions. The ammonium ions with rape markedly lowered the growth rate, the intensity of photosynthesis and biomass yield, with relation to the plants fertilized with nitrates. With corn the effect of both N-forms was similar and positive. The biomass of the rape using NH₄⁺, with relation to the plants fertilized with NO₃^- showed lower content of total N, and protein N, as well as markedly higher content of amino-acids of primary protein synthesis and their amides and free ammonium ions. Yet, the corn utilizing N-NH₄⁺ showed, as compared with the plants fertilized with NO₃^-, higher content of all studied organic N fractions. with similar content of free ammonium ions. This paper presents the thesis that the cause of the growth inhibition of rape fertilized with ammonium is low, as compared with corn, assimilation of NH₄⁺ ions drawn in the roots of this plant.