The Effect of High Carbon Dioxide and Temperature on the Total Chlorophyll Content in Grape Varieties

The study was carried out to investigate the effect of eCO2 (550ppm), eT (+3ºC) and interaction of eCO2+ eT on chlorophyll content of three grape varieties (Thompson Seedless, Bangalore Blue, and Dogridge). The cuttings of these three varieties were grown in specially designed open-top chambers, Free Air Carbon dioxide Enrichment (FACE) and Free Air Temperature Enrichment (FATE) facilities at ICAR-CRIDA. The experiment was laid out in two factorial RBD with varieties as one factor and treatments as another factor with six replications. Destructive sampling was done at 50 and 80 DAP and chlorophyll content (µg/g.fr.wt.) was analysed each time. At final sampling, all the three varieties have shown higher chlorophyll content under eCO2+ eT followed by eCO2. Among three varieties Bangalore blue has shown highest chlorophyll content (3.1±0.37) followed by Thompson Seedless (3.0±0.06) and Dogridge (2.4±0.08) under eCO2+ eT conditions. The plants under eT and ambient conditions have shown lower chlorophyll content than other treatments. The results from this experiment revealed that, the increase in atmospheric carbon dioxide concentration (eCO2) and temperature associated with future climates are expected to affect positively on chlorophyll content which can stimulate photosynthetic rate and ultimately leads to increase in biomass of crop.