Effect of a seaweed extract on the productivity of 'de Nules' clementine mandarin and Navelina orange

A seaweed extract (Goemar Spring Citricos(R)) from Ascophyllum nodosum was applied to trees of 'de Nules' clementine mandarin and Navelina orange at bud sprouting, at full bloom and at the end of the June drop, at a concentration from 0.15% to 0.30%. The seaweed extract increased the yield of 'de Nules' clementine mandarin by 11%. The application of 6 mg L-1 gibberellic acid (GA(3)) to this cultivar at full bloom increased the yield by 22%, and the combination of seaweed extract and GA3 resulted in a 41% increase of yield. Mean fruit weight was reduced by the GA(3)-seaweed extract combination, but the amount of marketable fruit was increased. In Navelina orange, seaweed extract at a concentration of 0.15% increased the yield by 8% whereas at a concentration of 0.30% it increased the yield by 15%. No significant differences were observed in the mean fruit weight of this cultivar.