195-14 Effects of Increase Atmospheric Carbon Dioxide On the Canopy Gas Exchange, Activity of Photosynthetic Enzymes and Growth In Coffee (Coffea arabica L. cv. Caturra).



Tuesday, October 18, 2011: 11:35 AM
Henry Gonzalez Convention Center, Room 007B, River Level

Nestor M. Riano1, Jorge A. Ramirez1, Luis F. Gomez1, Juan C. Lopez1 and Yamel Lopez2, (1)Plant Physiology, National Federation of Coffee Growers of Colombia / National Coffee Research Centre - CENICAFE, Manizales, Colombia
(2)Plant Physiology, Universidad Nacional de Colombia sede Palmira, Palmira, Colombia
In order to study the gas exchange, activity of photosynthetic enzymes and growth at leaves and whole coffee plant Coffea arabica L., under CO2 increase in the air [375 mmol (CO2) mol (air)-1 (control); 375+200 mmol (CO2) mol (air)-1 and 375+400 mmol (CO2) mol (air)-1], the plants were growing in pots into the open top chambers for six months. Whole plant gas exchange was measured under semi-controlled conditions in a chamber. The plant growth variables as height of the plant, stem diameter, number of branches, knots and leaves, and dry weight accumulated in the organs include roots, and leaf area were measured, as well as the variables related with the biochemical photosynthetic as chlorophylls, proteins, and the activity of Rubisco, PEPC and Glycolate oxidase. The statistical analysis reflected significant differences in all the variables evaluated under an atmosphere enriched with CO2 with respect to the control, mainly in the treatment with 375+400 mmol (CO2) mol (air)-1. The increased activity of Rubisco and Glycolate Oxidase enzymes, were related with the treatments and explain the behavior of the canopy photosynthesis. At the end of the experiment the plant growth variables measured were similar for the three treatments, which suggest the acclimatization of plants to high environmental concentrations of CO2 over the course of time.
See more from this Division: ASA Section: Climatology & Modeling
See more from this Session: Modeling Processes of Plant and Soil Systems Under Current and Future Climate: I