Research And Preparation Of The Combined Wettable Powder Of 44% Bentazon-Quinclorac

According to Li Shanlin's report,there are about 450 species of turf weeds in China and themajor weeds reached 60 kinds.Holding an extremely competitive,weeds contest with turf grass forresources,include water,fertilizer,light and space.Weeds promoted not only the degradation of theturf,but destroyed the landscape and spread the diseases and insect pests.The traditional methods tocontrol weeds are artificial weeding,which cost high and were no effective to underground parts ofperennial weeds.The rational mixture using of pesticides plays an important function in resistance delaying of pests,improving the control effect,reducing cost,prolonging service life,and reducepollution caused by pesticides etc.Therefore,the utilization of herbicide mixtures or mixedformulation will be efficient chemical methods for control turf weeds.Bentazon and Quinclorac,as 2 high efficiency and safe turf herbicides were chose in this study,where the optimum proportion were determined based on biometrics indoor.Although additivesscreening,combined wettable powder of 44% Bentazon-Quinclorac was prepared and proved qualified by product quality analysis.The research method and results of effect experiment in fieldare given below.1 The screening of optimum proportionTest materials barnyard grass,spiny amaranth,abutilon,and green bristlegrass were applied todetermine the toxicity of Bentazon and Quinclorac.The results when Bentazon tested showed,theEC₅₀ of 4 materials were 1470.57,355.77,482.90,and 1913.59 mg·ai/L respectively.When Quinclorac tested,the EC₅₀ were 76.29,603.28,1140.32,107.58 mg·ai/L respectively.By Colbymethod proved,the best synergism gained when the proportion of Bentazon and Quinclorac is 1∶1.Treatment on weeds and investigation were designed at proportion gradient 1∶1.5,1∶1.2,1∶1,1.2∶1,and 1.5∶1.The results showed the best control effect gained at the ratio 1.2∶1,which was theoptimum proportion of Bentazon and Quinclorac.2 The determination of the combined wettable powder formula of 44%Bentazon-QuincloracAfter single-dose processing of the combined wettable powder,carrier bentonite and 15% silicawere screened,optimum wetting agents A1,A2 and dispersant agents B1,B2 were determined.Complex formulation screening proved Al was the best wetting agent then.Additives as factor andaddition as level,3 factors at 3 levels orthogonal test was designed,from which the optimizedformulation of the combined wettable powder of 44% Bentazon-Quinclorac were determined asbelow: Bentazon 24%Quinclorac 20% Silica 15%Al 2%Bl 3%B2 1%Bentonite complement to 100%3 Quality analysis of the combined wettable powder of 44% Bentazon-QuincloracMethods commended by FAO and GB were able to measure the suspensibility,wettability,heat/cold storage stability,and fineness of the combined wettable powder.The results showed thecombined wettable powder of 44% Bentazon-Quinclorac:with good stability;suspensibility was82.33%; wetting time was 42 (less than 60)seconds;suspensibility after heal storage was 81.33%.After cold storage,particle size D₁₀ was 0.932μm,D₅₀ 1.726μm,D₉₀ 4.740μm,D₃ 0.678μm,D₉₇9.287μm,and Dav 2.457μm.Among them,particle sizes less than 2.000μm accounted for 61.04%;less than 5.000μm occupied 61.04%.Product size D₁₀ was 1.007μm,and D₅₀,D₉₀,D₃,D₉₇,Dav was 1.858μm,4.582μm,0.756μm,7.499μm,and 2.43μm respectively,where sizes less than 2.000μm and 5,000μm accounted for 55.74%,91.60% in turn.4 Field efficacy of the Combined Wettable Powder of 44% Bentazon-QuincloracAs test agents,the combined wettable powder of 44% Bentazon-Quinclorac possessed a goodcontrol effect on gramineae and broadleaf weeds in study.The best effect against crabgrass,goosegrass,and pennywort were 86.67%,82.14%,and 87.04% respectively,when effective componentdosage were 1056g·ai/ha (high amount),with 30 days later.With the same condition,while dosagewere 1584g·ai/ha (times amount),the control effect on three weeds mentioned were 93.75%,91.43%,and 97.22% respectively.Compared with control 48% Bentazon water agent and 50% QuincloracWP,the weeding effect was improved obviously and expanded the action spectra.Yet the effect oncreeping oxalis was poor,only 47.22% and 48.50%.In cline with the principle of economical,highefficient and environmental,effective component dosage 1056g /hm² as routine stems and leavesspraying treatment were commended.