Field evaluation of Prunus rootstocks for use in dried prune production

The California prune industry has historically utilized five rootstocks, Myrobalan seedling, ‘Myro 29C’, ‘Marianna 2624’, ‘Lovell’ and ‘Marianna 40’. The last statewide organized prune rootstock effort was planted in 1987. Since the conclusion of that experiment many more potential rootstocks for prune have been identified. In 2011, a non-replicated screening trial was planted to test 15 experimental rootstocks and 3 standard rootstocks nursery budded to ‘Improved French’. This experiment provides an initial evaluation of possible rootstocks that have previously not been tried with prune or have had very little field testing. Our results show a number of rootstocks, including some with moderate size controlling capabilities, hold promise as potential rootstocks for prune production in the future.