Abstract: Arsenic-reducing bacteria (Stenotrophomonas sp.TS28) and root exudates of rape,  wheat and pakchoi were used as experimental objects to study the effects of root exudates on the survival and arsenic reduction ability of arsenic-reducing bacteria TS28 and soil enzyme activities in arsenic contaminated soil. The results show that As(Ⅴ) in soil inhibits the survival of TS28, the addition of root exudates stimulates the survival of TS28,  and increases the survival number and time of TS28. Root exudates can affect the reduction ability of TS28,  which is related to its source. The root exudates of wheat have the best effect on improving the arsenic reduction ability of TS28,  and the reduction amount of As(Ⅴ) is increased by 45.86% within 10 d. TS28 decreases the activities of sucrase and dehydrogenase in arsenic contaminated soil,   the addition of root exudates increases the activities of urease,  acid phosphatase,  sucrase and dehydrogenase,  among which rape root exudates have the best effect.

Key words: root exudate; , soil; , arsenic-reducing bacteria; , survival; , reduction; , enzyme activity