Effect And Mechanism Of Echinacea Purpurea's Alkylamideson Alleviating Injury From Metolachlor In Rice

By selecting all kinds of raw materials based on the results of previous researches, it showed that echinacea root extracts can be used to reduce the harm of metolachlor on rice seedling. Then, it further studied the active effect of alkenamides in echinacea root on relieving metolachlor's phytotoxicity on rice and the extraction of alkenamides, and discussed the functional mechanism of alkenamides in Echinacea regarding to its detoxification effect on rice.Organic solvent extraction method is adopted to extract crude extract from the echinacea root that contain rich alkenamides and refine the crude extract based on the characteristics of alkenamides, so as to obtain the required alkenamides based on the features of alkenamides. HPLC test proved that the content of six components of the compound is very high, and the overall acquisition ratio is 1.2%.Indooor biological activity test proved that the alkenamides of Echinacea can relieve the phytotoxicity of metolachlor on rice, and alkenamide extracts of Echinacea in the agar culture-medium can be used to recover the suppression of herbicide on rice. The best recovery effect of rice regarding to the plant height, root height and fresh weight are 79.24%,75.49% and 82.44% of that in blank control group respectively.The results of tests on chlorophyll content, SOD activity and GSTs activity of rice showed that the chlorophyll content level does not have significant differences between the group uses Echinacea amide and the control group. Under the processing of herbicide only, the content of chlorophyll in rice has significant inhibiting effect. The chlorophyll a, chlorophyll b, and the total amount of chlorophyll of this group are 65.1%,67.2% and 65.7% of the blank control group respectively. The chlorophyll content of the mixed group of metolachlor and Echinacea amide has more significant effect on recovery than the herbicide group. The Chlorophyll a, chlorophyll b. and the total amount of chlorophyll of this group are 144.7%,132.8% and 141.0 of the herbicide group, and 94.1%,89.4% and 92.7% of the blank control group respectively.After processing with herbicides, the SOD activity of rice is tested as 914.23U/g.F, which is relatively higher than the blank control group. Meanwhile, the SOD activity of the blank control group, Echinacea amide group, herbicide group and the mixed group are 779.01 U/g.FW, 803.57U/g. FW and 801.32U/g.FW.The test results of GSTs activity proved that the use of echinacea amides can improve the GSTs activity of rice, enhance the detoxification metabolism of plants against herbicide, and recover the inhibiting effect of herbicide on rice. Its activity is 2.7 times of the blank control group and 2.14 times of the herbicide group.