Screening And Evaluation Of Herbicides In Maize-soybean Intercropping Pattern

In recent yaers,country vigorously promoted crop rotation and intercropping intercropping pattern supports compound,scientific use of cultivated land resources.Focus on promotion of maize/soybean(peanut)crop rotation in northeast China,in the huang-huai-hai region to promote maize/peanut(soybean)interplanting interplanting,promote maize/soybean interplanting interplanting in southwest region,in the northwest areas of mazie/potato(soybean)rotation(countries do hair[2015]no.59).The pattern includes gramineous crop of maize and broadleaf crop of soybean.In the patterns when weed,not only to control the pattern of gramineous weeds and broadleaf weeds,but also avoid cause unrecover able damage to the maize and soybeans.Therefore,the security screening on maize,soybean herbicide and weed control effect of herbicide to protect maize,soybean production and guide the use of herbicides in Maize-Soybean intercropping are important.This research used actually used in the production of maize or soybean herbicide screening,selected through screening test for evaluation of drug harm index safe herbicides.And then further in the laboratory and field production of herbicide phytotoxicity assessment,evaluation and economic benefit evaluation.The main results are as follows:1、Evaluation of PhytotoxicityDifferent herbicide treatments relative to the water control,disincentive to the strains of maize and soybeans higher shorter,stem thickening.Hazard index of 10 kinds of soil treatment with herbicide herbicide and 13 kinds of treating stems and leaves to filter out the maize and soybean safety or injury but could return to normal growth of herbicide.Elected 5 species soil treatment of Pendimethalin,S-metolachlor,Prometryn + Acetochlor + 2,4-D butyl ester,Acetochlor + Metribuzin + 2,4-D butyl ester and Acetochlor + Metribuzin.And 5 species stem-leaf treatment of Bentazone,Thifensulfuron methyl,Florasulam + Flumetsulam,Fomesafen+ Bentazone and Imazethapyr.The effects of the drug on mazie and soybean growth were further screened for herbicides.Soil treatment of Pendimethalin and Acetochlor + Metribuzin,maize and soybean plant height,stem diameter and dry matter weight of no significant difference with CK.S-metolachlor effect of intercropping maize,soybean plant height and stem diameter,but does not affect the accumulation of dry matter,the amount of dry matter accumulation of maize and soybeans low 10.71%and 4.17%respectively than water control.Thifensulfuron methyl of maize and soybean,whose plant height decrease,the high inhibition rate was 18.94%and 2.23%respectively than water control.Bentazone process of maize and soybean plants,high stem,dry matter and chlorophyll content were no significant difference.Different herbicides are applied in field production.Soil treatment S-metolachlor safer,maize growth inhibition rate was significantly lower than Oxyfluorfen,73.13%.Soybean growth inhibition rate was significantly lower than that of Acetochlor and Oxyfluorfen,low 88.83%and 91.13%respectively.At the time of Stem-leaf treatment,Bentazone more security than the other treatments.Thifensulfuron methyl followed.The drug of 6d,mazie and soybean was graded 1.After the drug,12d,mazie and soybean were restored to normal and the level of drug damage was 0.In an experiment with different concentrations of Thifensulfuron methyl,effects of low concentration Thifensulfuron methyl and spray 3 time of Thifensulfuron methyl treatment is safer.All of the drugs are 6d,and the maize is grade 1.When the medicine was 12d,the mazie returned to normal.Soybeans have not been hurt.Directional spray Fomesafen and Imazethapyr treatments on maize and soybeans more secure.The drug of 18d,there was no significant difference in the height of maize and soybean plants.In experiments with different methods,spray treatment on maize causes phytotoxicity.The treatment of the whole field spray Fomesafen caused phytotoxicity to maize,which was rated at grade 2 when the drug was in 12d.Nicosulfuron treatments damage to the soybean.2.Evaluation of efficacyDifferent herbicides are applied in field production.Soil treatment of S-metolachlor plant control effect of the number and fresh weight is 71.96%and 78.83%is higher than other herbicides.Thifensulfuron methyl weed control effect of the number and fresh weight is 73.88%and 96.1%.The soil herbicide Pendimethalin and Bentazone herbicide Bentazone were the least effective against weeds,with 60.58%and 49.66%respectively,with a fresh reefficacy of 67.12%and 83.82%respectively.Different herbicides are applied in field production.Oxyfluorfen weed strains were still significantly lower than the other,weed plant control higher than S-metolachlor and Acetochlor,respectively.Respectively were 70.26%and 35.28%.Stem-leaf of hand weeding in the treatment plant control and weight control was significantly higher than the others.Stem-leaf of Thifensulfuron methyl has a good effect.Its fresh and protective effect was 74.62%In an experiment with different concentrations of Thifensulfuron methyl,3 spray Thifensulfuron of processing and conventional Thifensulfuron dose spray for weed control effect after hand weeding,plant control>70%,fresh control>87%.In experiments with different methods,full field spraying weed is better than processed soybean line directional spray.Its protective effect was 70.04%to 81.87%and the fresh reproof efficacy was 88.51%to 91.70%.Soybean line orientation spray Fomesafen and Imazethapyr had the worst defensive performance,with a protective effect of 55.47%and 50.45%,respectively,with a fresh reproof of 78.91%and 76.68%respectively.3.Evaluation of the economic effectivenessTo be tested in field trials,Acetochlor effect long period,whose output than highest in soil treatment for 13.16%.S-metolachlor followed,Imazethapyr of maize injury serious,low economic benefit.Thifensulfuron methyl on maize and soybean that is safe,and has a better effect,higher output,output than the highest,14.09.In an experiment with different concentrations of Thifensulfuron methyl,low concentration Thifensulfuron methyl treatment of maize and soybean yields significantly higher than other Thifensulfuron methyl concentration process.Applying Thifensulfuron methyl treatment of 1g and 1.25g received far more input-output ratio than others,more than 40.In experiments with different methods,directed spray Imazethapyr treatment of maize yield is higher than the other,712.74kg.Directed spray Fomesafen treated soybean yield is higher than the other,49.5kg.The two types of medicine received far more input-output ratio than others,more than 30.4.The herbicide methodIn maize-soybean intercropping pattern,which is less weeds,you can use the more secure soil treatment agent Pendimethalin and stem-leaf treatment Bentazone to prevent weeds.In the field of maize-soybean intercropping pattern that weed are overgrown,the herbicide and its use should be used.For 1-2d after seeding,the application of the soil treating agent is S-metolachlor 2000ml/hm2.The stem-leaf was treated with a low concentration of Thifensulfuron methyl 15-19 g/hm2 in the mazie leaf 3-5.