Effects Of6Herbicides And4Allelopathic Plant Aqueous Extracts On The Seedling Growth Of Polygala Tenuifolia Willd.

In this project the effects of four premergence herbicides acetochlor,triflural,Pendimethalin,glyphosate, and four allelopathic plant Datura stramoniu L.,Helianthus annuus L.,Sorghum bicolor L.,Zea mays L. aqueous extracts on seeds germination and seedling growth of polygala tenuifolia willd..were studied by approach of laboratory, the effects of two postemergence herbicidesHaloxyfop-R-methyl and quizalofop-p-ethyl on seedling growth of polygala tenuifolia willd..wasinvestigated in pot experiment. And further determine the impact on the growth of polygalatenuifolia willd.and the herbicidal effect of premergence herbicides triflural、Pendimethalin、glyphosate and postemergence herbicides Haloxyfop-R-methyl、quizalofop-p-ethyl that werepreliminary selectioned in laboratory experiments.at the same time, the phytotoxicitysymptoms of polygala tenuifolia willd..and weeds were recorded in our experiments.The resultsare brought forward as following:1、Acetochlor reduce the germination rate of polygala but it didn’t reach significantdifference,however make vision radicle and seedling height growth severely restrained. Sowe think it is unsafe to polygala.2、Triflural increases the germination rate of polygala and reaches significantdifference,meanwhile the date of radicle and seedling height display it is safe to polygala.3、Pendimethalin increases the germination rate of polygala and reaches significantdifference，So we think it is safe to polygala,it can be used to weeding.4、glyphosate didn’t inflounce the germination rate of polygala,but it inhibition theseedling growth of polygala.however they are premergence herbicides, So we think it is safeto polygala,it can be used to weeding.5、The aqueous extracts of Helianthus annuus L.and Sorghum bicolor L.,under theconcentration of0.033g·ml^-1is safe to seedling growth of polygala and it can inhibit thegrowth of weed.6、The aqueous extracts of Zea mays L., under the concentration of0.05g·ml^-1is safe toseedling growth of polygala but it cann’t inhibit the growth of weed.7、The aqueous extracts of Datura stramoniu L., the concentration between0.01～0.033g·ml^-1is safe to seedling growth of polygala and it can inhibit the growth of weed. 8、Haloxyfop-R-methyl and quizalofop-p-ethyl are safe to the seedling growth ofpolygala,meanwhile they display good weed control effect for gramineous.9、The comprehensive advice of polygala field weeds:the chemical weed control ispriority to considering in large vision field;meanwhile we can supplement by crop rotation orintercropping allelopathy of plant,such as sunflowers、sorghum,to reduce the happening ofthe weeds harm.