Potential impacts of increasing atmospheric carbon dioxide on yield and plant growth of rice (Oryza sativa) and maize (Zea mays) crops

Abstract

Free air carbon dioxide enrichment (FACE) facility was used to conduct the experiments during 2011-12 and 2012-13 cropping seasons for assessing the growth and yield attributes of rice (Oryza sativa L) and maize (Zea mays L). The concentration of CO2 was kept 550± 30 ppm in enriched condition. The concentration of ambient condition was 395±30. Recommended doses of NPK fertilizers were given to both the crops. Plant growth and yield parameters were measured and analyzed for both the conditions. Assessment revealed that the plant height of rice and maize did not change significantly. A significant (F= 9.800; P<0.02) change was noticed in the post-harvest index of rice. However, there no change was noticed in the post-harvest percentage of maize. Leaf area of rice (P<0.01) and maize (P<0.005) increased significantly at flowering stage of plants under enriched CO2 environment over the ambient. Under elevated CO2 condition, biological yields of rice and maize were improved by 14.3% and 17.2% respectively. Carbon dioxide enrichment exposure improved the grain yield by16. 2% (P<0.02) and 13.8% ( P<0.02) for rice and maize respectively.