Figure 5. Detection of Ca^2 + concertrations in cucumber roots tips at 3 d after treatment.

(A–C) Confocal images of cucumber roots tips by Fluo-3 AM. (A) Cucumber plants grown under normoxic conditions (Control). (B) Cucumber plants grown under hypoxic conditions (Hypoxia). (C) Cucumber plants grown under hypoxia + 4 mM CaCl₂ treatment (Hypoxia + CaCl₂). The signal corresponding to the incorporated Fluo-3 is green. (D) The Ca²⁺ content (μg•μl⁻¹) of cucumber roots under normoxic conditions (control), hypoxic conditions (Hypoxia) and hypoxia + 4 mM CaCl₂ treatment (Hypoxia + Ca²⁺). Values are means ± SE of three independent experiments. Bars marked with dissimilar letters are significantly different from each other according to Duncan’s multiple range tests (P < 0.05).