Abstract:With in vivo and in vitro Tagetes erecta roots under light and dark as test materials, this paper studied the effects of their extracts on the glutathione S-transferase and protease activities and protein content in Tetranychus viennensis. The results showed that the chloroform extract of T. erecta roots had the highest light-activated activity, followed by water extract, and methanol extract. After treated with chloroform extract, the glutathione S-transferase and protease activities in T. viennensis increased markedly, while its protein content decreased obviously. The variation degree of T. viennensis protease activity and protein content was significantly higher when the chloroform extract came from the T. erecta roots under light, suggesting that there existed active matters in the extract, which could promote the activation of protease, and thus, the decomposition of protein in T. viennensis. The bioactivity of T. erecta metabolites was mainly of light-activated one.