Effects of different nitrogen forms on growth, phenolics, flavonoids and antioxidant activity in amaranth species

Higher plants, accumulate large number of polyphenolic compounds which are believed to act as defence compounds against different environmental constraints. Nitrogen (N) is a critical element for plant growth, absorbed as (NH 4 + ) and (NO 3 -), which affects plant growth and to some extent contributes to secondary metabolites accumulation. Greenhouse experiment was carried out to determine the effect of N forms on growth and phytochemical accumulation in Amaranthus species. Two amaranth varieties; AB6 and AB7 constituted the main plot while three N forms; ammonium, nitrate, ammonium nitrate and control (no N form) represented the subplot.