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.
