Effect of a seaweed extract on the productivity of 'de Nules' Clementine Mandarin and Navelina Orange

A seaweed extract (Goemar Spring Citricos®) 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 GA 3 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.