The effect of herbicides and biostimulants on polyphenol content of potato (Solanum tuberosum L.) tubers and leaves

The objective of the research was to determine the polyphenol content in the tubers and leaves of selected table potato cultivars cultivated using herbicides and biostimulants. A field experiment was conducted in Wojnów (52°12′59″N, 22°34′37″E), Poland (Multi-business ‘Solex’ Company) from 2012 to 2014. The experiment was a two-way random split-plot arrangement of plots with three replicates. The following factors were examined: three medium-early potato cultivars – Bartek, Gawin, Honorata, and five methods application of herbicides and biostimulants (Harrier 295 ZC, Sencor 70 WG, growth regulators Kelpak SL and Asahi, control where weeds were mechanically controlled). Polyphenol content was determined in fresh potato tuber mass by the spectrophotometric method using Folin-Ciocalteu reagent. The tuber content of polyphenols was affected by the cultivars, herbicides and biostimulants as well as weather conditions during the growing season. The herbicides and biostimulants increased the concentration of polyphenol compounds compared with the control tubers. Polyphenol content in potato leaves was significantly affected by cultivar traits only. Of the tested cultivars, Honorata and Gawin accumulated the most and the least polyphenols, respectively. Keywords: Cultivars, Herbicydes, Biostimulants, Potato