Application of Cysteine, Methionine and Amino Acid Containing Fertilizers to Replace Urea: The Effects on Yield and Quality of Broccoli

Abstract

A greenhouse experiment was carried out to determine the influence of replacing 80% of urea in broccoli fertilization with L-cysteine and L-methionine foliar spray at two concentrations 100 and 200 mgL-1 and amino acid containing fertilizer (AA) at 750 and 1500 mgL-1 on yield, nitrate accumulation, dry weight of head, vitamin C, phenolic compounds and total acidity. Replacing 80% of urea with AA increased the total acidity significantly (P ≤ 0.05). Elimination of 80% urea but foliar spray of cysteine (100 and 200 mgL-1), methionine (200) the percentage of dry weight significantly (P ≤ 0.05). Urea (250 kg ha-1) plus amino acids and amino acid Alone in Comparison with control (just 50 kg ha-1 urea) increased significantly (P ≤ 0.05) Yield. The content of vitamin C, decrease significantly (P ≤ 0.05) by the urea (250 kg ha-1) application with amino acids. Application of amino acid containing fertilizer (750 and 1500 mgL-1) along with urea (250 kg ha-1) increased nitrate accumulation.