E. Vangdal, A. Gibalova, J. Børve, I.L. Knutsen, M. Korosec, R. Vidrih, A. Leufven
Acta Horticulturae ; Volume 1120. p. 409–413.
In this work the effects of adding extra nitrogen, calcium and both nitrogen and calcium to apple trees in the fruit cell division phase were studied. Even though the given nitrogen and calcium did not give significantly higher content of N and Ca in the treated fruits, differences in the contents of some aroma compounds were found. Nitrogen treated trees gave apples with more hexanal, a compound known in unripe («green, grassy») apples. When both calcium and nitrogen were applied, the negative effect of nitrogen on aroma compounds was less pronounced. The aroma of these fruits was more similar to the controls. Using multivariate statistical analyses, the grouping of the different treatments during storage was confirmed. Foliar fertilization with nitrogen and calcium during the cell division phase had a significant effect on the amount of aroma compounds in apples at harvest and during storage.