Abstract: The research on the persistent of 14C-chlorsulfuron and its effect on the after reap rice through technique of nuclear trace shows that one wheat season after its application,about 25% of the chlorsulfuron remained in the soil.The residue raised with the increment of the application amount of chlorsulfuron. After one rice season and one wheat season(326 days),the residue of chlorsulfuron accounted for about 15% of the privitive dose.The residue of springapplied chlorsulfuron was higher than the residue of autumn-applied chlorsulfuron.The residue of chlorsulfuron in wheat stubble soil had a marked effect on the growth of after reap rice.The residue in root is much higher than in the other parts of the plant,which explains clearly that the negative effect of chlorsulfuron on the growth of root is related to the high accumalation of chlorsulfuron in root. 

Key words: chlorsulfuron, residue in soil, transfer coefficient, rice