Micropropagation of three species of aquatic plants.

An efficient protocol for in vitro propagation of three aquatic plant species (Cryptocoryne becketti, Cryptocoryne lutea and Rotala rotundifolia) was established. For the sterilization of the initial explants, 1.0 and 1.5% sodium hypochlorite was successfully employed for Rotala and for Cryptocoryne spp. respectively. Satisfactory shoot proliferation was obtained in Linsmaier and Skoog medium (1965) enriched with 0.5 mg l-1 naphtalene acetic acid (NAA) and two different concentrations of 6- benzylaminopurine (BAP) (1 or 4 mg l-1). Both BAP concentrations induced also adventitious root emission in all species. In the medium supplemented with 4 mg l-1 BAP the multiplication rate values were higher, but root number and length were lower than in the medium containing 1 mg l-1 BAP. For acclimatization in aquarium of the rooted clumps a natural condition-like soil (peat:clay:sand at 1:1:10/v:v:v ratio) offered better results in terms of shoot and root growth compared to Compo Cactea© commercial mix. Moreover, during this step better root systems developed in plantlets obtained in presence of 1 mg l-1 BAP during the proliferation-rooting-phase. Rotala showed the highest adaptability to in vitro propagation, since proliferation activity was very high; between the two Cryptocoryne species, no differences in proliferation and rooting were observed.