Expression Level of Carotenoid Biosynthesis Genes in Leaves Is Associated with Cold Tolerance of Zea mays L. Plants

The expression profile of the key carotenoid biosynthesis genes (ZmPSY1, ZmPSY2, ZmLcyE) was determined in the dynamics of cold stress and post-stress recovery in the leaves of Zea mays L. plants of four cold-tolerant (breeders' data) inbred lines (L-5580-1, L-6097-1, L-5254-3, and L-5272-6). It was shown that, under normal growing conditions, the expression level of all three genes in the L-5580-1 line was significantly higher compared to other lines. It was revealed that low-temperature exposure affects the trends of gene expression fluctuations in a similar way between the lines. It was determined that, in the stress dynamics, the co-expression pattern of the ZmPSY1 and ZmPSY2 genes in the leaves of L-5580-1 plants is coordinated with changes in the carotenoid content.