Study On Competitive Mechanism And Phytocide Of The Scirpus Planiculmis Fr. Schmidt And Cotton

The Scirpus planiculmis Fr.Schmidt is a perennial herb of Cyperaceae of Scirpus, resistanceto low temperature, salinity, temperature and wet, fast growth, suitable reproductive capacity andability, called one of the vicious weed. Cotton is one of the main pillars of the agriculturaleconomy in Xinjiang, and its scale of production, acreage, total production and yield rank first inthe country. The application of drip irrigation Scirpus multiply to create a suitable ecologicalenvironment, resulting the cotton fields Scirpus trend spreading increasingly worse.Study oncompetitive effects of the Scirpus planiculmis Fr. Schmidt and cotton.Observed the differentperiods the Scirpus planiculmis Fr. Schmidt and cotton morphological、physiological andbiochemical indicators. Based on this, select representative land, herbicide efficacy screening canbe applied to the cotton fields, figure out the control efficiency of the single agent. According tothe results, determined the mix of combination, screening combination, determination ofphysiological and biochemical indicators in the laboratory, ultimately determined the controlefficiency, herbicide combination of cotton safety.The Scirpus planiculmis Fr. Schmidt density10-30plants/m2, plant height, main root lengthshowed an increasing trend. With Scirpus planiculmis Fr. Schmidt density increased, plant height,main root length showed a significant decreasing trend, content of the chlorophyll、POD、SODactivity significant difference compared with the control; The Scirpus planiculmis Fr. Schmidtwas planted in mid-April, the performance is obvious of morphological、physiological andbiochemical indicators of cotton. Due to natural conditions and required for plant growth duringthis period, the intense of competition the Scirpus planiculmis Fr. Schmidt and cotton mechanismof competition, the crucial period of prevention control the Scirpus planiculmis Fr. Schmidt.The Scirpus planiculmis Fr. Schmidt and cotton distance0cm,5cm, cotton height, main rootlength showed an increasing trend, significantly difference. After the Scirpus planiculmis Fr.Schmidt spraying distances0cm of the cotton, a slight phytotoxic with cotton, physiological andbiochemical parameter significantly difference,10cm apparent improved performance. Distance0cm during the Scirpus planiculmis Fr. Schmidt POD activity, distance5cm of SOD activity,distance10cm of CAT activity significant difference of compared to the control. Thus, preventionand control Scirpus planiculmis Fr. Schmidt in cotton fields, distance below10cm of the Scirpusplaniculmis Fr. Schmidt and cotton, used artificial pull out,10cm farther, used chemical methodsfor prevention and treatment.Effects of herbicides on physiology and biochemistry of the Scirpus planiculmis Fr. Schmidt,a significant decrease in chlorophyll content compared with the control on the9th day aftertreating. A significant reduction in the soluble protein and MDA content was on the first day aftertreatment, and there were no difference with the control or significantly lower than the controlafter9d.However, the soluble protein and MDA content increased with the treatment10%glyphosate AS2.67g a.i./L and48%bentazone AS2.4g a.i./L. The protective enzymes （POD,CAT and SOD）activity of the Scirpus planiculmis Fr. Schmidt was significantly affected by theherbicide. The increased the label rate and times of10%glyphosate AS and48％bentazone AScompared with the control, significantly higher than the control, And other treatmentsperformance for the first rise, after gradually returned to the control level.Study of herbicide mixed with one of growth regulators, aften9d,gibberellin and48%BentazoneAS2.4g a.i./L、1.2g a.i./L, brassinolide and38%outeWP0.152g a.i./L、brassinolide and48%BentazoneAS2.4g a.i./L、1.2g a.i./L reduce the chlorophyll content andprotein content of the Scirpus planiculmis Fr. Schmidt, but protein content、CAT activity、POD activity and SOD activity were significantly increased. Through field plot trial found，48%BentazoneAS、38%outeWP0.152g a.i./L mixed with one of gibberellin(GA) andbrassinolide, prevention and control effective is better,10%glyphosateAS mixed with one ofgibberellin(GA) and brassinolide, prevention and control effective is poor, but10%glyphosateASmixed with ethephon prevention and control effective is better.Enhanced the Scirpus planiculmis Fr. Schmidt allelopathical potential improved with theherbicide concention in high concentration extract embodies apparent. With increase of theScirpus planiculmis Fr. Schmidt concentration of extracts, cotton seed germination rate hasdropped, enhanced the allelopamy of it. Qualitative analysis of the allelochemicals, differentherbicides from the Scirpus planiculmis Fr. Schmidt allelochemicals, this is inconsistent with therelated literature.Effects of prevention and control on three soil-applied pesticides of Scirpus planiculmisFr.Schmidt,50%acetochlor EC different treatments concentration have better control effect onScirpus planiculmis Fr. Schmidt, control effect above98%.48%Butralin EC daejeonrecommended amount or higher than the concentration, control effect above90%.Chemical control of cotton field Scirpus planiculmis Fr. Schmidt based on orthogonal design,oute, bensulfuron methyl, glyphosate and bentazone played a leading role in controlling Scirpusplaniculmis Fr. Schmidt based on the recommended field dosage.30d days after herbicidesapplication, the control efficacy of treatment2(10%glyphosateAS and10%penoxsulamEC and10.8%quizalofoppethylAS and48%bentazoneAS),treatment3(10%glyphosateAS and10%penoxsulamEC and10%PyrazosulfuronWP and30%bensulfuron methylWP) and treatment4(10%glyphosateAS and10.8%quizalofoppethylAS and30%bensulfuron methylWP and50%quincloracWP and38%outeWP) all reached above80%.The control effect of10%glyphosateAS,30%bensulfuron methyl WP,38%outeWP and48%bentazoneAS was significant, butconsidering the injury effect on cotton, orieentational spraying method was preferred sprayingmethod was preferred instead of direct spraying method.45d after the treatment, corns were dugout and immersed in water for20d, the germination of the parts below and zbove ground was notfound. Thus, suitable herbicide concentrations and mixtures provide a certain reference for thecontrol of cotton field the Scirpus planiculmis Fr. Schmidt.Determined four pesticides of single concentration,10％glyphosateAS1/4times andconcentrations above、38％oute WP each concentration、48％bentazoneAS1/16times andconcentrations above have better control effect on Scirpus planiculmis Fr. Schmidt,recombination of four herbicides, by orthogonal, screening out the newcombination,10%glyphosateAS53.4ml and48%bentazoneAS5ml and38%outeWP0.2g and30%bensulfuron methyl WP0.1g and10%glyphosateAS6.67ml and48%bentazoneAS5ml and38%outeWP0.4g and30%bensulfuron methyl WP0.2g.Multiplexed herbicide, direct spray, from prevention and control of the Scirpus planiculmisFr. Schmidt and cotton safety consideration, screening out a bettercombination,75%TrifloxysulfuronWP0.015g/L and40%Prometryn4g/L.From the cost view and control effects,75%TrifloxysulfuronWP0.015g/Land40%PrometrynWP4g/L is prevention and control the Scirpus planiculmis Fr.Schmidt the bestcombination.