Effects of environment and genotype on phenolic acids in wheat in the HEALTHGRAIN diversity screen.

Phenolic acid content and composition have been determined in 26 wheat genotypes grown in Hungary over three consecutive years and at three additional locations (France, United Kingdom, and Poland) during the third year. Fractions comprising free, soluble conjugated, and bound phenolic acids were analyzed using HPLC with measurements being made for individual phenolic acids in each fraction. Statistically significant differences in phenolic acid content occurred across the different growing locations with the average total phenolic acid content being highest in the genotypes grown in Hungary. The growth year in Hungary also had a large impact, especially on the free and conjugated phenolic acid contents. Certain genotypes were more resistant to environmental impacts than others. Of the genotypes with high levels of total phenolic acids, Lynx, Riband, Tommi, and Cadenza were most stable with respect to their total contents, whereas Valoris, Herzog, and Malacca, also high in phenolic acid content, were least stable. Of the three fractions analyzed, the free and conjugated phenolic acids were most variable and were also susceptible to the effect of environment, whereas bound phenolic acids, which comprised the greatest proportion of the total phenolic acids, were the most stable.