Table 2. Results of Multiple Regression Analysis: Equations Present the Significantly Influential Factors on the Single Phenolic Compounds of Red Leaf Lettuce (n = 48, α = 0.01)a.
| compound | equation | R2 |
|---|---|---|
| Cy3MG | = 1.075774 – 0.148608 × DAP + 0.019459 × PPFD – 0.000028 × PPFD2 + 0.003040 × DAP2 – 0.000077 × PPFD × DAP | 0.88 |
| Q3G | = 0.061983 – 0.012242 × DAP + 0.033398 × cultivar + 0.001004 × PPFD – 0.000002 × PPFD2 + 0.000215 × DAP2 | 0.69 |
| Q3MG | = 6.472664 – 0.765445 × DAP + 2.181619 × cultivar + 0.020639 × PPFD + 0.013099 × DAP2 | 0.77 |
| Q3Gc/L7Gc | = 0.761703 – 0.107507 × DAP + 0.236988 × cultivar + 0.007146 × PPFD – 0.000015 × PPFD2 + 0.001859 × DAP2 | 0.82 |
| chicoric acid | = 1.003199 – 0.108660 × DAP + 0.893134 × cultivar + 0.002311 × DAP2 – 0.021650 × cultivar × DAP | 0.75 |
| chlorogenic acid | = 0.932527 – 0.019782 × DAP | 0.45 |
| caffeoylmalic acid | = 0.170214 – 0.001731× DAP | 0.17 |
a
DAP, days after planting; PPFD, photosynthetic photon flux density in μmol m–2 s–1; cultivar, red oak leaf (1) and lollo rosso (2); Cy3MG, cyanidin-3-O-(6″-O-malonyl)-glucoside; Q3G, quercetin-3-O-glucoside; Q3MG, quercetin-3-O-(6″-O-malonyl)-glucoside; Q3Gc/L7Gc, quercetin-3-O-glucuronide/luteolin-7-O-glucuronide. The value of R2 displays the coefficient of determination.