Heat-induced TAG accumulation in wild-type, dgat1, pdat1, and tgd1 Arabidopsis seedlings. Levels of the four most abundant TAGs with the acyl composition 54:9, 54:8, 54:7, and 54:6 were determined in 2-week-old dgat1-1, pdat1-2, pdat1-3, and tgd1-1 seedlings kept at 22°C (white bars) or 45°C for 90 min (black bars). Data represent means ± sd, n = 4. Asterisks denote statistically significant differences (P < 0.05) from 22°C. FW, Fresh weight.