Study On Screening And Application Technology Of Herbicides In Silybum Marianum L.Field

In order to solve the question that there is lack of hebicides in Silybum marianum L.field,the safety and weed control effect of soil-applied herbicides Thifensulfuron,Prometryn,Alachlor,S-metolachlor,Oxyfluorfen,Oxadiazon,Dibutalin and Pendimethalin on Silybum marianum L.were conducted.At the same time,the safty of applied foliar-applied herbicides Quizalofop-p-ethyl,Fluazifop-P-butyl,Haloxyfop-R-methyl,Sethoxydim,Fomesafen,Lactofen,Bentazon and Pyroxsulam on Silybum marianum L.were studied in this paper.Different application periods of Thifensulfuron,Prometryn,Alachlor,S-metolachlor,Oxyfluorfen,Oxadiazon,Dibutalin and Pendimethalin were studied through potted experiment.It is obvious that the sooner applied herbicide the safer to Silybum marianum L..A field experiment was carried out to tested the safty of Silybum marianum L.and weed control effect of Thifensulfuron,Prometryn,Alachlor,S-metolachlor,Oxyfluorfen,Oxadiazon,Dibutalin and Pendimethalin.It showed that Thifensulfuron,Prometryn and Oxyfluorfen can effectively control grass weed but not broad-leaf weed.Alachlor,S-metolachlor,Oxadiazon,Dibutalin and Pendimethalin can effectively control both grass weed and broad-leaf weed.Thifensulfuron,Prometryn,Alachlor,Oxyfluorfen and Oxadiazon cause the yield reduction,should not applied in Silybum marianum L field.S-metolachlor 96%EC 720?1 008 g a.i.·hm-2,Dibutalin48%EC 720?1 440 g a.i.·hm-2 and Pendimethalin33%EC 495?990 g a.i.·hm-2 have no significant effect both on yeild and the content of silymarin,could be applied in Silybum marianum L.field.The pot experiment was conducted to study the influence of foliar-applied herbicides Quizalofop-p-ethyl,Fluazifop-P-butyl,Sethoxydim,Fomesafen,Lactofen,Bentazon and Pyroxsulam when ilybum marianum L.was 4 leaves to 6 leaves.The result showed that the treatment applied of Fomesafen,Lactofen,Bentazon,Pyroxsulam,all Silybum marianum L.were dead,so Fomesafen,Lactofen,Bentazon,Pyroxsulam can not be applied on 4 leaves to 6 leaves Silybum marianum L..It was safe to applied Quizalofop-p-ethyl,Fluazifop-P-butyl,Haloxyfop-R-methyl and Sethoxydim in Silybum marianum L.field..The suitable application doses were Quizalofop-p-ethyl 5%EC 30?45ga.i.·hm-2,Fluazifop-P-butyl 15%EC 11.5?22.5ga.i.·hm-2,Haloxyfop-R-methyl 10.8%EC 120?160 g a.i.·hm-2,Sethoxydim 12.5%EC 40?75 g a.i.·hm-2.In our studies,the optimum application period and doges of soil-applied herbicides S-metolachlor,Dibutalin,Pendimethalin and foliar-applied herbicides Quizalofop-p-ethyl,Fluazifop-P-butyl,Haloxyfop-R-methyl were confirmed.S-metolachlor,Dibutalin,Pendimethalin could be applied in Silybum marianum L.field filled up the blank that there were no pre-emergence hebicides could be used in Silybum marianum L.field,provided theoretical basis for chemical weeding,provided a guarantee for the further expansion of the cultivated area of Silybum marianum L.and had practical application merit.