Changes in Carbon Fixation, Tuberization, and Growth Induced by CO2 Applications to the Root Zone of Potato Plants

The root systems of potato plants (Solanum tuberosum L. var. Russet Burbank) treated with CO(2) for 12 hours showed an increase in dry matter as early as 2 days after the treatment. When treated plants were allowed to grow for 3 to 6 weeks there was a substantial increase in tuberization. In addition, there was an increase in stolon length, number of tubers per stolon, and overall dry weight after the enrichment of the root zone with CO(2). Plants treated with CO(2) showed higher concentrations of malic and citric acids and of the cations Mg(2+) and Ca(2+). The effect of CO(2) was more dramatic when CO(2) was applied to the root zone than when it was applied to the shoots.