J. Norrie, T. Branson, P.E. Keathley
A replicated commercial field trial evaluated the effects of Ascophyllum nosodum marine plant extract (Acadian Liquid Seaweed Concentrate; LSC) on yield and cluster quality of Thompson seedless grapes. Treatments consisted of a control, LSC at 2.34 and 3.5 L/ha applied at pre-bloom, post-bloom and sizing stages, and LSC at 2.34 L/ha with an additional treatment at bud break. Plots received a standard fertility management program in addition to specific treatments. Compared to the control, LSC at 2.34 L/ha, LSC at 3.5 L/ha and LSC at 2.34 L/ha with bud break treatment gave yield increases of 25, 14 and 13%, respectively. Heaviest individual clusters were harvested from the LSC 2.34 L/ha treated plots that averaged 0.431 kg/cluster, a 9% increase over the control. LSC at 2.34 L/ha with bud-break treatment produced berries that were 25% heavier than controls. LSC (at 2.34 L/ha) treated berries were 22.4% heavier than controls. A series of commercial samplings was also undertaken to explore effects on a wider range of varieties and locations. Results indicate a consistent increase in berry size (from 6.1 to 8.6%), weight (from 3.2 to 29%) and firmness (from 8.6 to 27.1%) for several varieties and locations. However, Brix levels tend to be lower in treated berries. This information is discussed.
Norrie, J., Branson, T. and Keathley, P.E. (2002). MARINE PLANT EXTRACTS IMPACT ON GRAPE YIELD AND QUALITY. Acta Hortic. 594, 315-319
DOI: 10.17660/ActaHortic.2002.594.38
Ascophyllum nodosum, biostimulant, foliar extract, grapevine, yield and berry quality

Acta Horticulturae