What was done
The authors grew ornamental Spathiphyllum cv. Merry plantlets for a period of five weeks in novel culture vessels of their design on a sugar-free liquid medium at low light intensity (photon flux density of 45 µmol m^-2 s^-1) in controlled-environment chambers maintained at atmospheric CO2 concentrations of either 375, 1000, 2000 or 3000 ppm.

What was learned
Relative to the growth experienced by the plantlets exposed to ambient air of 375 ppm CO2, the plantlets exposed to 1000, 2000 and 3000 ppm CO2 produced 39%, 81% and 129% more shoot dry weight, respectively, plus 316%, 639% and 813% more root dry weight, respectively, for total CO2-induced biomass enhancements of 61%, 127% and 185%.

What it means
For this particular plant, as well as many other species that have been similarly tested (see Growth Response to Very High CO2 Concentrations in our Subject Index), several-fold increases in the air's CO2 concentration pose no problem at all to their growth and development. In fact, the more CO2 there is in the air, the more biomass the tested plants have typically produced.