Cultivating Cucumber Plants for Research

Cucumber (Cucumis sativus cv. Libelle F1, Seston Seemned OÜ, Estonia) seeds were sown in 1 L plastic pots filled with a mixture (1:1) of sand and commercial potting soil (Biolan Oy, Finland) and cultivated according to standard practices in a controlled-conditions plant growth room as in our previous studies [39 (link),40 (link)]. In short, light intensity of 300–400 μmol m⁻² s⁻¹ at the level of plants was provided for 12 h light period by Philips HPI/T Plus 400 W metal halide lamps. Air temperature was 24 °C at day and 20 °C at night and air humidity was maintained at 60–70%. The plants were watered daily to soil field capacity, and fertilized every three days with commercial NPK (nitrogen, phosphorus and potassium) fertilizer. Approximately 3–4-week-old, 20–30 cm tall plants with four to five fully expanded leaves were used in the experiments.