Effects of Environment and Variety on Alkylresorcinols in Wheat in the HEALTHGRAIN Diversity Screen

Abstract

Alkylresorcinols (AR), phenolic lipids found in high amounts in whole grain wheat and rye, can be used as biomarkers for these cereals. The content (on a dry matter basis) and homologue composition of AR were determined in 26 wheat varieties grown in Hungary in 2005-2007, as well as in the United Kingdom, France, and Poland in 2007. There was a significant effect of year, location, and variety on both total AR and individual AR homologue content (p<0.001). A warm and dry climate generally resulted in higher AR contents, whereas high precipitation especially during plant development and grain-filling resulted in lower contents. There was a significant negative correlation between AR content and thousand-kernel weight (p<0.001), which may be explained by the warm and dry climate giving smaller kernels with higher AR content. The difference between varieties was generally consistent, with highest and lowest AR contents for the same varieties during different years and at different locations (p<0.001). Total AR content was correlated with the relative proportions of the different homologues, with a relatively lower concentration of homologues C17:0 and C19:0 and a lower C17:0/C12:0 ratio at higher overall contents. The results show that AR content is a highly heritable phytochemical component but that it is also affected by the environment.