Degradation of TCP in soil planted with alfalfa（Medicago sativa L.）

[Objective] The research aimed to study the degradation of 2, 4, 6-trichlorophenol (TCP) in soil planted with alfalfa (Medicago sativa L.), as well as to provide references for the Chlorophenols phytoremediation technology in the practical application. [Method] By the use of pot culture experiment in greenhouse, the phytoremediation effect of alfalfa on TCP-contaminated soil, the growth conditions of alfalfa, as well as the effect of TCP on the activity of soil polyphenol oxidase, dehydrogenase and catalase were studied. [Result] After the alfalfa was grown for 75 d, the TCP content in soil of three different concentrations treatments (low, middle and high) decreased dramatically within 15 d, and then the decreasing rate was gradually slow; on the 30th d of cultivation, the fresh weight of treated alfalfa showed no significant difference with the control (P0.05), indicating that TCP in soil had inhibition effect on the growth of alfalfa; alfalfa could significantly enhance the activities of polyphenol oxidase