Genetic specificity of magnesium nutrition in sunflower

Magnesium content was analyzed in five of the most grown sunflower hybrids in Serbia, as well as in different populations of wild sunflower species: Helianthus agrophyllus (5), Helianthus annuus (4), Helianthus neglectus (3), Helianthus petiolaris (5), Helianthus tuberosus (5). Magnesium content in the populations of wild sunflower species ranged from 317 to 824 mg/100 g DW. The highest magnesium content was found in Helianthus petiolaris and the lowest in Helianthus tuberosus. Different populations within each species differed significantly in magnesium content. The highest variation coefficient was found in Helianthus tuberosus and the lowest in Helianthus petiolaris. Magnesium concentration in hybrids was significantly different as well, and in two years it was in average between 575 and 813 mg/g DW. The results suggest that genetic variability between magnesium concentrations in wild species and hybrids of sunflower is very high. This should be taken into consideration when requirements for mineral nutrition are analyzed, as well as when wild species are included in breeding programs.