The quantum yield for CO2uptake in C3and C4grasses

✍ Scribed by Russell K. Monson; Robert O. Littlejohn; George J. Williams

• Publisher: Springer
• Year: 1982
• Tongue: English
• Weight: 402 KB
• Volume: 3
• Category: Article
• ISSN: 0166-8595
• DOI: 10.1007/bf00040713

✦ Synopsis

The quantum yield for CO 2 uptake was measured in C3 and C4 monocot species from several different grassland habitats. When the quantum yield was measured in the presence of 21% 02 and 340cm 3 m -3 CO2, values were very similar in C3 monocots, C3 dicots, and C 4 monocots (0.045-0.056 mole CO 2 • molequanta absorbed). In the presence of 2% 02 and 800 cm 3 m-3 CO2, enhancements of the quantum yield values occurred for the C3 plants (both monocots and dieots), but not for C4 monocots. A dependence of the quantum yield on leaf temperature was observed in the C3 grass, Agropyron smithii, but not in the C4 grass, Bouteloua gracilis, in 21% 02 and 340cm 3 m -3 CO 2. At leaf temperatures between 22-25°C the quantum yield values were approximately equal in the two species.