Abstract. Fertilization with (NH₄)₂SO₄ and foliar nutrition lowered soluble sugar content in carrot. Storage roots of plants fertilized with Ca(NO₃)₂ contained the least amount of phenolic compounds. Foliar nutrition did not have any effect on phenolic compound concentrations in carrot. Foliar nutrition and treatment with NH₄NO₃, (NH₄)₂SO₄ or CO(NH₂)₂ did not affect carotenoid concentrations.

The effect of nitrogen fertilizer and foliar nutrition
on the content of carotenoids, soluble sugars
and phenolic compounds in carrot

Summary

The pot experiment on cultivation of carrot ‘Kazan F₁’ was conducted in 2004-2005. The research comprised two sub-blocks with and without foliar nutrition. The plants received foliar nutrition thrice: with 2% urea solution, with 1% solution of Supervit R multicomponent fertilizer and again with 2% urea solution. Soil treatment with nitrogen applied within the sub-blocks comprised: control (unfertilized with nitrogen), Ca(NO₃)₂, NH₄NO₃, (NH₄)₂SO₄ and CO(NH₂)₂. Both foliar nutrition and fertilization with (NH₄)₂SO₄ decreased concentrations of soluble sugars in carrot. The storage roots of plants fertilized with Ca(NO₃)₂, contained the least amount of phenolic compounds. Foliar nutrition did not have any influence on phenolic compound content in carrot. Neither foliar fertilization nor treatment with NH₄NO₃, (NH₄)₂SO₄ or CO(NH₂)₂ affected carotenoid concentrations.