Response of Important Tropical Tree Species to Elevated CO2

Global warming plays a major role in climate change which is caused mainly due to increase in CO₂ level in the atmosphere. Present study attempted to evaluate four important tropical tree-species, Tectona grandis, Ailanthus excelsa, Casuanna equisetifolia and Casuarina ,Jungkuhniana for adaptation to elevated levels of CO₂ at nursery stage. The study was conducted inside the poly tunnels and CO₂ enrichment was done to double the concentration. Seedlings in poly tunnel without CO₂ enrichment served as control The short term experiments revealed that of the four species studied, casuarinas performed well under elevated CO₂ conditions in terms of all growth parameters studied. The performance of teak alone was poor indicating adverse effect of CO₂ enrichment on morphological traits of tbiB species as seen by reduced leaf area, lesser dry' matter accumulation both in shoot and ischolar_main system and poor Seedling Quality Index at elevated CO, levels. Thus, in the present study, all the species except teak showed a positive response to CO₂ enrichment in terms of morphological traits while Cuuarina equisetifolia and C. junghuhniana showed better growth and seedling quality indicating their better adaptability to elevated CO₂level.