Influence of calcium content of tissue on hyperhydricity and shoot-tip necrosis of in vitro regenerated shoots of Lavandula angustifolia Mill.

In the present study, the effects of two CaCl₂.2H₂O levels (440 and 1320 mg L^-1) and two subcultures were evaluated on in vitro shoots of Lavandula angustifolia cv. Provence Blue. Ca²⁺ content of the apical, middle and basal portion of shoots was determined. Increasing CaCl₂.2H₂O level in the culture medium increased tissue Ca²⁺ content and decreased hyperhydricity. Shoot-tip necrosis also decreased with 1320 mg L^-1 CaCl₂.2H₂O, but it did not occur in the second subculture. The middle and basal portion had higher Ca²⁺ content than apical portion. In non-hyperhydric tissues, there were smaller and more juxtaposed cells. Scanning electron microscopy of the leaves demonstrated that trichomes from in vitro leaf surface occurred in smaller quantities.

True lavender; Micropropagation; CaCl₂.2H₂O_, Leaf anatomy; Ultrastructure; Trichome