Effects of partial replacement of nitrate by amino acids on growth, nitrate accumulation and mineral composition of pakchoi (Brassica chinensis L.)

摘要

Two hydroponic experiments were carried out to determine the influence of partial replacement of nitrate by glutamic acid (Glu) and glutamine (Gln) in nutrient solution on the growth, nitrate accumulation and mineral composition of pakchoi (Brassica chinensis L.). The results showed that both amino acids inhibited the plant growth with reducing the ratio of NO_3~--N/amino acid-N (AA-N). When 20% NO_3~--N in the solution was substituted with Glu or Gln, the nitrate, Ca and Mn contents of plant shoot depressed, and N, P contents increased, while K, Mg, Fe, Cu, Zn contents varied respectively dependent on Glu or Gln.