Growth, yield and quality attributes of a tropical potato variety(Solarium tuberosum L. cv Kufri chandramukhi) under ambient and elevated carbon dioxide and ozone and their interactions

摘要

The present study was designed to study the growth and yield responses of a tropical potato variety (Solarium tuberosum L. cv. Kufri chandramukhi) to different levels of carbon dioxide (382 and 570 ppm) and ozone (50 and 70 ppb) in combinations using open top chambers (OTCs). Plants were exposed to three ozone levels in combination with ambient CO_2 and two ozone levels at elevated CO_2. Significant increments in leaf area and total biomass were observed under elevated CO_2 in combination with ambient O_3 (ECO_2+AO_3) and elevated O_3 (ECO_2 + EO_3), compared to the plants grown under ambient concentrations (ACO_2+AO_3). Yield measured as fresh weight of potato also increased significantly under ECO_2+AO_3 and ECO_2 + EO_3. Yield, however, reduced under ambient (ACO_2+AO_3) and elevated ozone (ACO_2 + EO_3) compared to ACO_2 (filtered chamber). Number, fresh and dry weights of tubers of size 35-50 mm and ＞50 mm used for direct consumption and industrial purposes, respectively increased maximally under ECO_2 + AO_3. Ambient as well as elevated levels of O_3 negatively affected the growth parameters and yield mainly due to reductions in number and weight of tubers of sizes ＞35 mm. The quality of potato tubers was also modified under different treatments. Starch content increased and K, Zn and Fe concentrations decreased under ECO_2+AO_3 and ECO_2 + EO_3 compared to ACO_2 + AO_3. Starch content reduced under ACO_2+AO_3 and ACO_2 + EO_3 treatments compared to ACO_2. These results clearly suggest that elevated CO_2 has provided complete protection to ambient O_3 as the potato yield was higher under ECO_2+AO_3 compared to ACO_2. However, ambient CO_2 is not enough to protect the plants under ambient O_3 levels. Elevated CO_2 also provided protection against elevated O_3 by improving the yield. Quality of tubers is modified by both CO_2 and O_3, which have serious implications on human health at present and in future.