Multielement Analysis of Leaves

The YFEL were collected and freeze-dried (−45°C, 1 mbar) for 36 h. Hereafter, each sample was weighted. All samples were digested using an UltraWAVE Pressurized Microwave Digestion System (Anton Paar) with 2.5 mL of HNO₃ (70%, v/v) and 1 mL of H₂O₂ (15%, v/v), and subsequently diluted to 50 mL (Hansen et al., 2013). Elemental analysis was performed with a model no. 5100 ICP-OES (Agilent Technologies), using external calibration, drift check samples, and certified reference material for optimal data quality (Olsen et al., 2016). For the 40-d–old plants, leaves were taken from the same position on the plants, and similar-sized leaves were selected for the elemental analysis. Data were tested with a one-way ANOVA t test.