Abstract: With the development of industrialization,especially the rapidly increasing use of fossil fuels,the atmospheric carbon dioxide concentration is rising. The continuous increase of CO₂ concentration will impact the growth and development of plants largely,and the coordination of various hormones in plants is key to regulate plant growth and development. Therefore,it is significant and promising to study the change of endogenous hormone content and the intrinsic response mechanism of plant after elevated atmospheric CO₂ concentration. At this stage,the research on plant root morphology,growth and development under high CO₂ concentration is widespread,but few studies have been done with plant endogenous hormones. This paper reviewed the research achievements of other scholars,and found that elevated CO₂ accelerated the net assimilation rate,improved the net photosynthesis,concurrently accumulated growth-promoting hormones,reduced the growth-inhibiting hormone,which subsequently regulated the allocation of assimilates and promoted the growth of plants. The paper also summarized the effects of elevated CO₂ concentration on IAA,GA₃,ABA,CK and ET,and analyzed the effects of CO₂ on related hormone synthesis and gene expression of signal transduction pathway,including the changes of the contents and the internal mechanism of the endogenous hormones in different plants. The future research directions in this field were also discussed.

Key words: elevated CO₂ concentration, endogenous hormones, responding mechanism