Fig. 2.

Lipid responses to chilling include effects related to genetic distance and chilling tolerance. The relative abundance of specific lipid species exhibits multiple sequential changes in the first 24 h of exposure to chilling stress. In all panels, the x-axis indicates the time in hours (h) (A) Mole percent abundance of lipids relative to all fatty acid-containing lipids for the following lipid classes: monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglcyerol (DGDG), and phosphatidylcholine (PC) in foxtail millet, Urochloa, and sorghum. (B) Unsaturation index, calculated as the average number of double bonds per fatty acid for all fatty acid-containing lipids: MGDG, DGDG, and PC. P-values were determined using Fisher’s least significant difference (LSD). *P-value <0.05, **P-value <0.01, and ***P-value <0.001. (C) Structural models of major lipids MGDG, DGDG, and PC, where blue indicates the hydrophilic head group and orange indicates the hydrophobic tail group. (D) Total unsaturation index, calculated as the average number of double bonds per fatty acid for all fatty acid-containing lipids. For all samples, n was between three and eight biological replicates.