NEUBERG, M., PAVLÍKOVÁ, D., ŽIŽKOVÁ, Eva, MOTYKA, Václav, PAVLÍK, Milan. Different types of N nutrition and their impact on endogenous cytokinin levels in Festulolium and Trifolium pratense L. Plant, Soil and Environment. 2011, 57(8), 381-387. ISSN 1214-1178. E-ISSN 1805-9368.

This study aims to reveal the effects of two various systems of nitrogen nutrition (sidedress application or injection application) on toxicity of NH4+ and mixed nutrition. We investigated whether NH4+ or NH4NO3 application causes significant changes in the endogenous levels of cytokinins (CK), whole plant N and their effects on yield of selected plants. Ammonium sulphate or ammonium nitrate were used as N source in the pot experiment. The yield of Festulolium and Trifolium pratense L. was more substantially enhanced after sidedress application of both ammonium sources in comparison with injection application. The accumulation of CKs in plants is in correlation with their N status. Proportions between individual CK forms remained relatively steady and their dynamics exhibited similar trends after N application. Our results indicate that the negative effect of the application of NH4+ on the growth of Festulolium and clover plants could be effectively modulated by presence of NO3−.