Genetic variability for concentrations of essential elements in tubers and leaves of Jerusalem artichoke (Helianthus tuberosus L.)

Data on the concentration of essential elements in the Jerusalem artichoke (Helianthus tuberosus L.) as valuable nutritional information is available only for a limited number of accessions and for tubers or leaves analyzed separately. For research or breeding of the Jerusalem artichoke a comprehensive overview of the extent of genetic diversity in existing germplasm is needed. As such, a diverse Jerusalem artichoke collection was analyzed in order to determine concentrations of essential elements separately in tubers and leaves and to assess the potential usability of accessions in breeding programs aimed at improving the quality of a Jerusalem artichoke's vegetative parts for feed and food.Concentrations of analyzed essential elements in leaves and tubers were significantly different. Of all the analyzed essential elements in leaves (N, P, Ca, Mg, K, Fe, Mn, Zn and Cu) Ca was the most abundant (36 g/kg), while in tubers it was only the fourth of the nine analyzed elements. The Ca/P ratio was approximately the same in tubers of all accessions which corresponds to a desired ratio for cattle feed (1:1–2:1). The leaves contained 18 times more Ca than P. Except for the lack of P in the Jerusalem artichoke herbage, there was an adequate amount of studied mineral elements for use as cattle feed (ruminants).It was found that tubers contain an adequate amount of macro- and microelements when used as food, and the element content was similar to or greater than in the other root crops. Accessions with the lowest K/(Ca + Mg) ratio were among accessions from Montenegro with ratio a of 5.8 which is still higher than the prescribed ratio for cattle feed of up to 2.2.By combining all of the obtained results through multivariate analysis, it was discovered that a group of accessions from Montenegro has potentially the best mineral composition for further work. One possible solution to overcome inappropriate mineral element ratios in leaves and tubers could be the usage of their mixtures for cattle feed, but further studies are required before a conclusion on its success can be made.

► Essential element concentrations were analyzed in Helianthus tuberosus L.
► N, P, Ca, Mg, K, Fe, Mn, Zn and Cu were analyzed in 141 Jerusalem artichoke accessions.
► Mineral composition of leaves and tubers was significantly different.
► Overcoming inappropriate element ratios can be done by mixing tubers and leaves.
► Montenegrin accessions had the best mineral composition for breeding forage cultivars.