Figure 4.

Lipid content in tomato wild-type (Wt) and SO RNA interference mutant (Ri) plants grown under normal growth conditions (0, day) and after being exposed to eleven days extended dark stress (11, day). Total polar lipids (a), total galactolipids (b) and individual galactolipids, (c,d) as well as the ratio between the galactolipids (e), total phospholipids (f) and individual phospholipids (g–i) were quantified by Trace GC Ultra as their methyl esters of the constituent fatty acids after two-dimensional thin-layer chromatography. First dimension was chlorophorm:Methanol:H₂O (65:25:4, v/v/v) followed byChlorophorm:Methanol:NH₄OH: Isopropylamine (65:35:5:0.5, v/v/v/v) and visualization under UV. Abbreviations are: digalactosyl-diacylglycerol (DGDG); monogalactosyl-diacylglycerol (MGDG); phosphatidylglycerol (PG); phosphatidylcholine (PC); phosphatidylethanolamine (PE). The bars are the average values ± SE (n = 3). The values denoted with different letters are significantly different according to the Turkey-Kramer HSD test (JMP 8.0 software, [37]; p < 0.05). Different lower case letters indicate differences between SO mutant and wild-type plants within the same treatment. Different upper case letters indicate significant difference within the plant genotypes in response to treatment. The data for SO-compromised plants represent the mean for SO Ri 131 and SO Ri 421 mutants.