The Influence of Partial Pressure of Carbon Dioxide upon Carbon Metabolism in the Tomato Leaf

Abstract

The incorporation of radioactive carbon into various photosynthetic products was investigated with tomato plants in atmospheres containing between 40 and 1400 parts/10⁶ carbon dioxide. A significantly greater proportion of ¹⁴C entered sucrose and alcohol-insoluble material at high concentrations of carbon dioxide. Incorporation into glycine and serine was significantly greater at lower carbon-dioxide concentrations. The pool size of these intermediates was also determined and it was concluded that in the presence of high partial pressures of carbon dioxide the flow of carbon from the photosynthetic cycle through the C² pathway is decreased.