Evaluation of Engulf® adjuvant with nitrogen for breaking dormancy in blackcurrant (Ribes nigrum)

Abstract

During the 2013 spring two different nitrogen sources (calcium nitrate and Break-N™) were applied using a motorised knapsack sprayer to dormant blackcurrants with and without the addition of a super penetrant surfactant (Engulf®) for dormancy breaking. Trials were conducted in Nelson at two grower sites, consisting of Ben Ard and Magnus blackcurrant varieties. Bud break and flowering was advanced by 5-10 days with the combination of the super penetrant surfactant and either nitrogen source. A Nitrogen source applied alone did not influence bud break or flowering. The length of flowering was condensed on Magnus and a more even and earlier fruit maturity occurred on both varieties with the combination of the super penetrant surfactant and nitrogen. The importance of these findings for the blackcurrant industry is discussed.