The effect of a seaweed concentrate on the in vitro growth and acclimatization of potato plantlets

The seaweed concentrate 'Kelpak' is used commercially in the greenhouse and field to improve plant quality. 'Kelpak' was added to the in vitro culture medium of potato cv. 'BP1' and also applied as a leaf/soil drench immediat ely after transplanting. The addition of 0.25% seaweed concentrate to the m edium improved plantlet quality and led to better establishment in the gree nhouse. No beneficial effect of seaweed concentrate in the tissue culture m edium was observed if a second cutting was part of the micropropagation pro cess. Additional application of 0.5% seaweed concentrate in the greenhouse to plantlet cuttings derived from tissue culture was not beneficial.