| Isatis indigotica Fortuneis is an important Chinese herbal medicine in China.Due to its recognized curative effect,its annual demand reaches more than 10,000 tons.However,in its planting process,weed control is the main difficulty,and the cost of putting into weed control is the highest.In this study,the weed species in I.indigotica field under drip irrigation under mulch in Karamay area were investigated,and the dominant weed species in I.indigotica Fortune field were identified.Because there is no weed control agent registered in I.indigotica Fortune crops at present,the safe herbicide for Iscais indigotica Fortune was screened out indoors,and field experiments were carried out in the field to further identify the safe and effective herbicides for I.indigotica Fortune and provide scientific basis for weed control.The results are as follows:1.Broad-leaved weeds were the dominant weeds in I.indigotica Fortune field under mulch drip irrigation in Karamay area.There are 11 families and 27 species of weeds in I.indigotica field under drip irrigation in Karamay area,among which 9 families and 14 species are dominant weeds.In June,Portulaca oleracea and S.nigrum had the highest relative abundance in I.indigotica Fortune field.In July,the populations of Chenopodium album,S.nigrum and abutilon hemp were the largest,and their relative abundance values were higher.In August,Chenopodiaceae weeds still have the largest number,followed by abutilon and Solanum nigrum.2.The best concentration of soil sealing herbicides suitable for I.indigotica field was screened out in laboratory.The effects of six herbicides with different concentrations on germination rate,plant height,cotyledon length,cotyledon width and average radicle length of Radix Isatidis were studied by pot culture and Petri dish culture.The germination rate was not affected by the treatments of metolachlor,oxyfluorfen,butralin and flumioxazin,and there was no significant difference among the treatments with different concentrations.When the concentration of pendimethalin was higher than 80m L/667m~2,the germination rate of I.indigotica was inhibited,and the higher the concentration of prometryn,the more obvious the inhibition was.The germination rate of I.indigotica was not affected by metolachlor,oxyfluorfen,butralin and flumioxazin.Metoclopramide,butralin,oxyfluorfen,prometryne and flumioxazin had no effect on radicle growth of I.indigotica.Butyridamole and flumioxazin had no effect on the plant height of Radix Isatidis.Except oxyfluorfen,metolachlor,pendimethalin,butoxydine,oxyfluorfen and flumioxazin had no effect on the growth of cotyledon length and cotyledon width of I.indigotica.3.In view of weeds in I.indigotica Fortune field under mulch drip irrigation in Karamay area,it is recommended to use pendimethalin and metolachlor to spray the soil before sowing.The treatment dose is33%pendimethalin EC 120m L/66 7 m~2,and the recommended dosage is 50m L/667m~2.In this study,six soil treatment herbicides,namely pendimethalin,sec-butyl,oxyfluorfen,flumioxazin,metolachlor and prometryn,were selected to treat the soil of I.indigotica Fortune before sowing.The results showed that pendimethalin and metolachlor were relatively safe to I.indigotica Fortune.Among them,the highest relative emergence rate of I.indigotica Fortune treated with metolachlor was 90.98%,but the control effect of weeds was not as good as that of other herbicides.The average density of weeds treated with flumioxazin was 7.53 plants/㎡15 days after treatment.Flumioxazin seriously affected the emergence of I.indigotica Fortune or died after emergence,and the relative emergence rate of Iscais indigotica Fortune was only 58.81%.After treating the soil with six herbicides,the root length,fresh weight and dry weight of I.indigotica Fortune treated with six herbicides were significantly different from those of the control,which indicated that herbicides had certain influence on the growth and development of I.indigotica Fortune. |
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