Isoflavone concentrations in soybeans suitable for growing in Europe

Abstract

Isoflavones are nutraceuticals with many different medical benefits found abundantly in soybean (Glycine max (L.) Merr.) seeds. The prerequisite of utilising this valuable source of bioactive compounds and creating quality stock for the pharmaceutical and functional food industries is the screening of available soybean germplasm for isoflavone content. The objectives of this research were to determine the isoflavone concentrations (total isoflavones, daidzein, genistein, glycitein) in 22 high-yielding soybean genotypes, to investigate their variability and explore the effect of different weather conditions on isoflavone phenotypes. Field trials were set up as a randomised complete block design with two replicates in three consecutive years (2010 - 2012) at the Agricultural Institute Osijek (Osijek, Croatia). Chosen genotypes belonged to 00 - II maturity groups (MGs) suitable for growing in almost all European regions. Results showed the existence of genetic diversity among the tested plant material. The influence of genotype and year were both statistically significant. The divergence determined by the analysis of variance (ANOVA) and confirmed by the pair-wise similarity based on the Euclidean distance, confirmed that this set of genotypes was suitable for the use in future crossing programmes aiming to produce cultivars superior in isoflavone content in comparison to the existing ones.