CO2 enrichment can produce high red leaf lettuce yield while increasing most flavonoid glycoside and some caffeic acid derivative concentrations
Carbon dioxide (CO2) enrichment is a common practice in greenhouses to increase crop yields up to 30%.
Yet, reports on the effect on foliar phenolic compounds vary. We studied the effect on two red leaf lettuce
cultivars, grown for 25 days in growth chambers at CO2 concentrations of 200 or 1000 ppm, with some
plants exchanged between treatments after 11 days. As expected, head mass increased with higher
CO2 concentration. Regression analysis, corrected for head mass, showed increased concentrations of
most flavonoid glycosides at high CO2 concentrations while only some caffeic acid derivatives were
increased, and not uniformly in both cultivars. Sugar concentrations increased with CO2 concentration.
Generally, conditions in the 10 days before harvest determined concentrations. We suspect that phenolic
compounds were mainly accumulated because plenty of precursors were available. The results indicate
that CO2 enrichment can result in high yields of red leaf lettuce rich in phenolic compounds.
Becker, C.; Kläring, H.-P. 2016. CO2 enrichment can produce high red leaf lettuce yield while increasing most flavonoid glycoside and some caffeic acid derivative concentrations. Food Chemistry 199, 736–745.