GENETIC AND BREEDING STRATEGIES TO LOWER FREE ASPARAGINE CONTENT IN WHEAT GRAIN

The presence of acrylamide in food is a difficult regulatory compliance issue for the food industry, since the European Commission issued Benchmark Levels and codes of practice for food products in 2017. In cereal derivatives, free asparagine content is a key factor in acrylamide formation (Raffan & Halford, 2005). Then, the use of cereal grains with low free asparagine level may help to reduce dietary acrylamide intake. Little information is available about the genetic control of this trait. Environmental factors and field management practices influence asparagine level in cereal grains. This may have contributed to the failure of the selection of appropriate genetic resources for breeding. So far, few quantitative trait loci (QTLs) for free asparagine concentration have been identified in different studies, but their contribution to the phenotypic variability of the analysed trait is controversial, with the major QTLs determined on different chromosomes, highly depending on the used population (Emebiri, 2014; Rapp et al., 2018; Lavoignat et al., 2024). Currently, different research lines are ongoing at the Institute of Agricultural Biology and Biotechnology (CNR, Italy) about this topic. First, specific bread wheat varieties that are characterized by low amounts of free asparagine and low environmental influence were identified within a panel of cultivars available for the Italian market, and their acrylamide-forming potential was evaluated (Tafuri et al., 2023; Covino et al., 2024). Furthermore, a genome-wide association study was performed in durum wheat and six quantitative trait nucleotides associated to this trait were identified. These data were joined with metabolomic analyses to determine specific genes and metabolic pathways involved in free asparagine accumulation in wheat grain (Tafuri et al., in preparation). These results pave the way to identify candidate genes involved in free asparagine accumulation, as well as genetic resources which could be useful for future breeding programs.