Media derived from brown seaweeds <Emphasis Type="Italic">Cystoseira myriophylloides</Emphasis> and <Emphasis Type="Italic">Fucus spiralis</Emphasis> for in vitro plant tissue culture

In the present study, the effect of seaweed extract (SE) from Fucus spiralis (Fs), Cystoseira myriophylloides (Cm) and Laminaria digitata (Ld) on in vitro plant tissue culture was examined. Combination of 25?% of SE from Cm with 25?% of MS medium increased adventitious shoot regeneration from Nicotiana benthamiana leaf discs explants by 620?%, when compared to the conventional regeneration medium. Similarly SE from Fs and Ld enhanced regeneration by about 500?%. However, when increasing SE to 50?%, only Cm significantly enhanced shoot regeneration. The effect of SE was also evaluated on in vitro micropropagation of N. benthamiana, grape, plum and apricot by assessing shoot length, number of leaves and internodes. When used alone but at lower concentrations (2.5 and 12.5?%), SE from Fs and Cm resulted in at least the same efficacy as MS alone for micropropagation of N. benthamiana shoots. However, for micropropagation of grapevine, plum and apricot woody plants, a combination of 50?% of SE from Cm or Fs with 50?% of their conventional micropropagation media was necessary. Rooting was also enhanced in N. benthamiana and grapevine, and was correlated with their higher concentrations of indole acetic acid when compared to SE from Ld. This finding, in addition to mineral analysis data, suggests that SE of Fs and Cm contain necessary nutrients and growth regulators to allow their use as medium for in vitro plant culture.