Effecots of Doubled CO₂ Level on the Growth and Development of Rice(Oryza sativa L,cv.Aixiangnuo)

Rice plant (Oryza Sativa L,cv. Aixiangnuo) was grown at 350 and 700ppm CO₂ open top chambers respectively after transplanting.Some characteristics of growth and development of the plant were observed.Results showed that rice grown at doubled CO₂ concentration,compared with that grown at ambient air,its root dry weight increased by 23%,plant height increased by 12%,number of seed set/panicle increased by 29% and grain weight/plant increased by 41%.Current research progress in this area was also discussed.