2013 ASHS Annual Conference

Acadian Seaweed extracts (ASE) have been used in wine grape production to improve plant establishment, rachis length, increase set, and to enhance yields.  In addition to these responses, visual improvements in color uniformity have been observed following applications of ASE, potentially indicating increased uniformity of maturity.  The objective of this study was to evaluate the effects of ASE on yield, and brix uniformity of 'Pinot Noir' grapes grown on the central coast of California.  A commercial 'Pinot Noir' vineyard in Soledad, CA, was selected for this trial.  Large blocks were paired by rootstock and clone, and assigned to either a grower standard practice or ASE (Acadian LSC, Acadian Seaplants Limited) treatment.  ASE treatment consisted of a full season application program at recommended rates and timings.  Samples taken approximately one month before commercial harvest showed a significant increase in cluster weight in ASE treated clusters.  Untreated clusters had more berries with shrivel than treated clusters.  Brix measurements from composite berry samples indicated lower brix on ASE treated clusters.  This higher bunch weight and lower brix in ASE treated fruit may be a result of the increased early shrivel in control fruit.  No differences in juice pH were detected, and the amount of juice per gram of berry was similar in both treatments.  When individual berries in a bunch were measured for brix, ASE  treated bunches showed less variation in brix.  Across all of the samples, ASE treated fruit had a smaller range in brix than did the control fruit.  This reduction in variation in brix comes primarily from fewer berries with very low brix measurements in the ASE treated fruit.  Yield at commercial harvest was 7.4% higher in ASE treated blocks, and brix was 0.55 degrees higher.  These results indicate the potential to extend applications of ASE beyond improving rachis length, berry set, and yield to increasing the uniformity of berries both within bunches and across vines.