Phytoene synthase 1 (Psy-1) and lipoxygenase 1 (Lpx-1) Genes Influence on Semolina Yellowness in Wheat Mediterranean Germplasm

Abstract

Phytoene synthase 1(Psy1) andlipoxygenase 1(Lpx-1) are key genes involved in the synthesis and catalysis of carotenoid pigments in durum wheat, regulating the increase and decrease in these compounds, respectively, resulting in the distinct yellow color of semolina and pasta. Here, we reported new haplotype variants and/or allele combinations of these two genes significantly affecting yellow pigment content in grain and semolina through their effect on carotenoid pigments. To reach the purpose of this work, three complementary approaches were undertaken: the identification of QTLs associated to carotenoid content on a recombinant inbred line (RIL) population, the characterization of a Mediterranean panel of accessions forPsy1andLpx-1genes, and monitoring the expression ofPsy1andLpx-1genes during grain filling on two genotypes with contrasting yellow pigments. Our data suggest thatPsy1plays a major role during grain development, contributing to semolina yellowness, andLpx-1appears to be more predominant at post-harvest stages and during pasta making.