Organic farming methods affect the concentration of phenolic compounds in sea buckthorn leaves

Summary in the original language of the document

- Berries, juice and other products of organically cultivated sea buckthorn (Hippophae rhamnoides L., Eleagnaceae) are in great demand because of their beneficial health effects. The availability of berries is not sufficient especially for locally growing market. However no research has been done on the effects of farming methods on the quality of sea buckthorn tissues before. We established a field experiment to study the effects of organic farming methods on the concentra-tions of phenolic compounds in leaves of two Finnish sea buckthorn cultivars ”Terhi” and ”Tytti”. 560 one and half years old seedlings were planted into 9 spatial blocks in coastal area in Merikarvia, western Finland in 2003. Different fertilizers and mulches were applied to the cultivars. Leaf samples were collected from the cultivars in the end of the first growing season. Eleven different hydrolyzable tannins and 14 other phenolic compounds were detected in chemical analysis with High Performance Liquid Chromatography (HPLC). The amount of phenolics varied between different mulches. The plastic mulch decreased the concentrations of phenolics compared to the other mulches used. The number of significantly increased hydrolyzable tannins was same in both cultivars, but the concentrations of individual compounds varied between them.