The Effect of Nitrous Oxide on the Seedling Growth and Development of Helianthus annuus Linn, and Zea mays Linn.

Abstract

Many studies have attempted to explain the effects of atmospheric pollutants on growth and various parameters of functioning of plants. Nitrous Oxide (N2O) is the third and last greenhouse gas accounted for in the Philippine greenhouse gas inventory, with a warning effect 310 times that of CO? (Gozun, 2003), The objective of this study is to determine the effects of nitrous oxide (N2O) on the seedling growth and development of Helianthus annus Linn, and Zea mays Linn. Both plants were subjected to treatment with N2O at varying lengths of exposure in a glass chamber. Then the following were taken and measured: plant form and general leaf appearance, root length, shoot length, root-shoot ratio (RSR), and physiological parameters. Results showed that there is a decrease in number of plants unaffected by N2O on its plant form and general leaf appearance. The root length of Zea mays L. showed a decrease while Helianthus anmius L. showed the reverse. Both plant species showed an increase in shoot length at longer lengths of exposure with N2O. No remarkable changes were observed in gross composition and percentage composition in both plant species. For chlorophyll absorbance, Zea mays L. seedlings readings showed a decreasing absorbance as the length of exposure with N2O increases but increased at 16-minute exposure, but the Helianthus annuus L. showed the reverse. Based on the result, N2O has an effect on plant form and general leaf appearance of the two plant species. Also, no significant difference where noted on the effect of N2O on root length, root-shoot ratio, gross composition, and percentage composition. Difference on shoot length of Zea mays L. and chlorophyll absorbance of both plant species showed significant results.