Reducing set in ruby seedless grapes with gibberellin

Ruby Seedless is a red seedless variety used as a table grape and for the freezer. The clusters are well filled to compact. In some vineyards, looser clusters would be desirable to reduce bunch rot and to facilitate packing. Gibberellin sprays reduce set in Thompson Seedless and several wine varieties, so trials were established with Ruby Seedless to determine the possible benefits.