The Control Effect And Safety Evaluation Of Herbicide In Broomcorn Millet Farmland

Panicum miliaceum L.is the main cultivated crop in arid and semi-arid regions in China.In the production of broomcorn millet,weeds are one of the main factors influencing the growth and production,and artificial weeding take time and energy,meanwhile,unfavorable to mechanized production,while the existing herbicide varieties are rarely registered in broomcorn millet.Our test selects four herbicides used in the production of cereal crops,and each herbicide is set up to four doses.The effects of different herbicides treatments on weed control in Panicum miliaceum L.Farmland and the effect of plant dry matter accumulation,functional leaf photosynthetic performance and yield after heading broomcorn millet were investigated,and the residual broomcorn millet spike and farmland soil residues were determined after spraying herbicide,and the following main conclusions were obtained:(1)Spraying herbicide can effectively control weeds in broomcorn millet,and the effect is different.Herbicide 2-amylso dium dosage treatmentand single-dipyridamole sulfonate is 1.5 kg/hm2 squared and weed control effect was decreased at late growth stage.Herbicide fresh weight control effect was also decreased to different degrees after 30 d of applying pesticide,the lowest 6.3 %.Triazole benzene sulfonate was not effective in the treatment of the dose of weeds,and the 15 d was less effective after taking the drug,but then it went up but then began to decline again.Single-dipyridamole sulfonate were 1.8 kg/hm2,2.1 kg/hm2,2.4 kg/hm2 squared and benzene,azole,2 methyl sodium each dose the best weed control effect of applying pesticide,fresh weight of weed control effect on corn millet is higher,in the whole stages for most fresh control effect of various processing close to even reach 100%.(2)Under herbicide treatment,top three leaves,the remaining leaves,stems,leaf sheath dry matter accumulation of broomcorn millet show the tendency to decrease after the first increase after heading,spike,the ground dry matter accumulation of broomcorn millet appeare the upward trend after heading.The dry matter accumulation of various organs of broomcorn millet was decreased significantly after spraying herbicide.(3)The relative content of chlorophyll in the top three leaves of broomcorn millet and the leaf area of the top three leaf,single plant leaf area were decreased with different herbicides treatments.However,there was no significant difference between the chlorophyll content and the artificial weeding treatment in broomcorn millet top three leaves of spraying herbicide,but the broomcorn millet leaf area of spraying herbicide and artificial weeding showed significant difference.(4)The dosage of the herbicides resulted in yield decreased of broomcorn millet under different degrees,which were significantly lower than the control yield of artificial weeding,but were significantly higher than that of spray equal water.The dosage of single-dipyridamole sulfonate is 2.4 kg/hm2,the yield of broomcorn millet grain is decreased by 10.31 %,the amount of benzene-2 methyl so dium is 0.3 kg/hm2,the yield of broomcorn millet grain reduced by 9.42 % compared to artificial weed control,which is significantly higher than that of other herbicide treatment.(5)The results of herbicide residue detection showed that there were no corresponding herbicide residues in the broomcorn millet spike samples and broomcorn millet farmland soil samples of the dosage of herbicide-dipyridamole.The herbicide residues were not detected in the broomcorn millet spike samples of the dosage of benzene-2-methyl so dium,but the corresponding residues were checked out in the soil samples of broomcorn millet farmland.To sum up,according to the weed control effect and broomcorn millet yield results,recommend application of sulfonate in broomcorn millet field before seedling,the recommended dosage for 2.4 kg/hm2,can achieve safe and efficient weed prevention in broomcorn millet field,and the effect of the broomcorn millet yield is relatively small.Herbicide-2-methyl sodium the degradation characteristics of the residues in soils are further studied to confirm the safety of the weed control in broomcorn millet field,and the recommended dosage is 0.3 kg/hm2.