Abstract
In order to investigate the possibility for use to control environmental pollution, Kenaf(Hibiscus cannabinus L.) was used to obtain information of their growth and $CO_2$ response under different temperatures and $CO_2$ concentration. The highest percentage of germination and aboveground dry mass of Kenaf were found at 30$^{\circ}C$ and 35$^{\circ}C$ by 89.0% and 3.2g, respectively under different temperatures. The amount of $CO_2$ absorption and aboveground dry mass production of Kenaf were higher than those of maize during the whole growing period and the last sampling of aboveground dry mass of Kenaf and maize were 252.9g and 200.8g, respectively. The highest plant height was found at 400ppm by 131.0cm and the next was in the order of 600ppm by 1293cm, and 800ppm by 108.8cm. Leaf area was higher in the order of 400ppm > 600ppm > 800ppm, whereas leaf dry mass was in the order of 800ppm > 600ppm > 400ppm under different $CO_2$ concentration, showing that leaf became thicker as $CO_2$ concentration was increased. Days from seeding to flowering became shorter by 13 days in 35/25$^{\circ}C$ compared with 25/15$^{\circ}C$ between two temperature regimes and they also became shorter as $CO_2$ concentration was increased. Aboveground dry mass was higher in 35/25$^{\circ}C$ than that of 25/15$^{\circ}C$ between two temperature regimes. while it was increased in the order of 800ppm > 600ppm > 400ppm as CO2 concentration was increased. Temporal changes of leaf dry mass during growth period showed no difference between $CO_2$ concentration in 25/15$^{\circ}C$ , but the highest of it was found at 800ppm in 35/25$^{\circ}C$. The highest temporaI increase of root dry mass was found at 800ppm in 25/15$^{\circ}C$, but 35/25$^{\circ}C$ showed no difference between different $CO_2$ concentration.
