Effects of different levels of glycine in the nutrient solution on the growth, nutrient composition, and antioxidant activity of coriander (Coriandrum sativum L.)

Abstract

A nutrient solution experiment was performed using sand culture to evaluate the effects of different glycine levels on the growth and nutrient uptake of coriander (Coriandrum sativum L.). Different glycine concentrations of 0, 5, 10, 20, or 40 mg L−1 were applied to plants via Hoagland’s nutrient solution in a completely randomized design with four replications and under greenhouse conditions. The results showed that leaf SPAD (soil and plant analysis development; an indicator of leaf greenness) value, stem diameter, and fresh and dry weights of shoots and roots were significantly increased by 10 mg L−1 glycine in comparison to the control plants. Application of glycine at 40 mg L−1 reduced many plant growth parameters, whereas leaf proline concentration was increased. All glycine levels except for 40 mg L−1 increased root fresh weight. Leaf protein content was increased by glycine applied at 10 or 20 mg L−1, whereas leaf antioxidant activity was increased at all glycine levels. Application of glycine increased leaf concentrations of nitrogen and potassium (at 10 mg L−1), magnesium (at 5 mg L−1), and zinc (at all glycine levels) compared to the control plants. The results indicate that moderate level of glycine (10 mg L−1) in the nutrient solution can improve the growth and nutritional quality of coriander.