Chemical Control of Herbicide Monosulfuron Plus Propazine 44% WP against Weeds in Millet Fields and Study on Factors Influencing Yield of Millet

[Objective] The paper was to resolve the poor efficacy or phytotoxicity problems in promotion of herbicide monosulfuron plus propazine 44% WP. [Method] Using orthogonal test and Duncan＇s new multiple range statistical analysis with four factors four levels and three factors two levels, the effects of factors such as herbi- cide dose, irrigation water volume, quality of soil preparation and soil moisture content on chemical control of monosulfuron plus propazine 44% WP against weeds and millet yield were compared in the test. [Result] Seven factors all had great impact on control effect of monosulfuron plus propazine 44% WP against weeds, of which her- bicide dose, irrigation water volume, quality of soil preparation and soil moisture content were the most important factors affecting millet yield. According to millet yield and economic benefit, the optimal scheme to ensure safe, efficient and economic control of monosulfuron plus propazine 44% WP against weeds was as follows： the dose of monosulfuron plus propazine 44% WP was 1 800 g/hm2, the soil was treat- ed after sowing and before seedling emergence; the soil should be smooth and sol- id; the soil moisture should reach 15%; the fields should not be irrigated after herbi- cide application, and the damage of weeds in millet fields could be effectively con- trolled within 45 d during high efficacy duration, especially the damage of dicotyledonous weeds. [Conclusion] The study provided useful information for comprehensive technology of weeds control and ensuring high yield and good harvest of millet.

Pre-emergence herbicides affect seedling emergence of tropical forest tree species

Testing techniques to reduce weed infestation is a crucial step in developing direct tree seeding systems. The use of pre-emergence herbicides may be an alternative to manual weeding techniques, but so far, information on how they affect the seeds of native tree species is scarce. We established a greenhouse experiment to evaluate the effects of four pre-emergence herbicides (atrazine, diuron, isoxaflutole and oxyfluorfen) on weed suppression and seedling emergence and early growth of seven tropical forest tree species (Annona coriacea Mart., Citharexylum myrianthum Cham., Cordia ecalyculata Vell., Peltophorum dubium (Spreng.) Taub., Psidium guajava L., Pterogyne nitens Tul. and Schinus terebinthifolia Raddi). The experimental design was a randomized complete block design with five treatments and five replicates. The treatments consisted of a single dose of each pre-emergence herbicide and a control. Throughout the 60 days after sowing we evaluated weed cover and seedling emergence and early growth of tree species. Overall, our results suggest that all tested herbicides reduced weed cover; however, they also negatively affected tree species seedling emergence. Of the four herbicides tested, atrazine and diuron showed the greatest effects on tree seedling emergence, oxyfluorfen was least aggressive towards native species and isoxaflutole was most effective in weed control. Native tree species varied in their responses to herbicides, indicating that future experiments should increase the number of species tested as well as investigate how seed traits can affect the species responses to different herbicides.

Control Effect Evaluation of Herbicides for Malignant Weed Nut Grass in Sugarcane Field

In order to screen herbicides with ideal safety characteristics to control malignant weed nut grass in sugarcane field, 20% thifensulfuron methyl WP and 65% MCPA·ametryne·diuron WP were selected for the field efficacy trial. The results showed that 20% thifensulfuron methyl WP and 65% MCPA·ametryne·diuron WP had good control effect on nut grass. The optimum dosage of 20% thifensulfuron methyl WP and 65% MCPA.ametryne-diuron WP was 1 125 g/hm^2 （effective ingredients 225 g） and 3 150 g/hm^2 （effective ingredients 2 047.5 g）, respectively. These two herbicides should be dissolved in 675 kg water per hectare and applied in the vigorous growth period of nut grass （height 10-15 cm） with oriented stem leaf spraying. The control effect after 15 days could be above 87.9%.

Water Hyacinth Control by Glyphosate Herbicide and Its Impact on Water Quality

The aim of this study was to evaluate the herbicide glyphosate under aquatic environment conditions, in a controlled and closed experimental field, in the management of water hyacinth (Eichhornia crassipes) in reservoirs. Twenty reservoirs (polyethylene water tanks) with storage capacity of 1000 liters were used, without water flow and without evapotranspired water replacement (worst case), being 04 for each treatment. The adult plants were placed in the water tanks to provide 90% surface occupation of the reservoir. Five treatments with four repetitions were considered, being: 1) Reservoir colonized by water hyacinth without control;2) Reservoir colonized by water hyacinth, controlled by glyphosate;3) Reservoir colonized by water hyacinth, controlled by freezing;4) Reservoir without water hyacinth and glyphosate application and 5) Reservoir without water hyacinth and no glyphosate application. The glyphosate herbicide was used at the highest recommended dose, 7.0 L·ha-1 or 3360 g of acid equivalent per ha, applied using carbon dioxide precision equipment (backpack sprayer), providing a flow rate of 200 L·ha-1. The water samples were collected at the time of application, 6, 12, 18 and 24 hours after application and also at 2, 4, 8, 16, 32 and 64 days after application, in the morning, always at the same time, also between 8 and 9 h. The method used for determination of residues was by high performance liquid chromatography (HPLC) and mass spectrometry with a mass selective detector. Low concentrations of glyphosate and aminomethylphosphonic acid (AMPA) were found in both reservoirs that received application of the product. The half-life of glyphosate in water to the reservoirs with water hyacinth was 11 days and in the reservoirs without water hyacinth was 21 days. The results show a low potential of environmental impact of glyphosate use in the control of water hyacinth in reservoirs.

Effects of Different Herbicides on Maize Growth and Weed Control in Maize Fields

Effects of four herbicides(paraquat, acetochlor, nicosulfuron and atrazine) on the growth of maize and control effect of plant quantity and fresh weight of weeds were studied. The results showed that 15 days after spraying the herbicides on weeds,the prevention and control effect of paraquat on weeds was the optimum, and its effects on the plant quantity and fresh weight of weeds were above 81.57%; the prevention and control effect of acetochlor on weeds was the second best; the prevention and control effect of atrazine on weeds was the worst, and its effects on the plant quantity and fresh weight of weeds were only 51.04% and 37.86%. After 30 or 45 days, the prevention and control effect of atrazine and nicosulfuron on weeds in the maize fields was better than the other herbicides, and their effects on the plant quantity and fresh weight of weeds were higher than 70.00% and 85.00%. Acetochlor and paraquat had certain phytotoxicity to the growth of maize after about 15 days, and its leaves became yellow and grew slowly. On the whole, nicosulfuron had good prevention and control effect on weeds and had no phytotoxicity to the growth of maize.

Kudzu Response to Foliar Applied Herbicides

Chemical control is presently the most cost-effective means to control kudzu;however, some of the herbicides labeled for kudzu control have substantial non-target toxicity, poor selectivity, high cost, long soil persistence, high soil mobility and/or high use rates. The present study evaluated other herbicides for efficacy in suppressing aboveground kudzu biomass in replicated field trials at three sites over two years. A single application of aminopyralid, triclopyr or metsulfuron resulted in at least 90% kudzu suppression in the following season at two locations. After a second year of treatment those herbicides and fluroxypyr produced at least 90% kudzu suppression, and 100% kudzu control was reached on some test plots. Glyphosate, glufosinate and mesotrione were less effective in controlling kudzu. Given the rapid growth potential of kudzu, complete eradication should be pursued. None of the herbicides evaluated in the present study could reliably achieve eradication of mature kudzu with two applications, so additional control efforts would be required.

Effects of Different Herbicides on the Control of Malachium aquaticum L. and Poa annua L.

In this experiment,the effects of 13 kinds of herbicides( or mixtures) on the control of two kinds of weeds were studied by pot cultivation with the broadleaf weed Malachium aquaticum L. and Gramineae weed Poa annua L. as the materials. The results showed that the herbicide MCPA-Na had the best and fastest control effect on M. aquaticum L.,and all the M. aquaticum L. died 7 d after treatment;it was followed by the other four herbicides including MCPA-Na + clethodim,MCPA-Na + quizalofop-p-ethyl,bentazon and nicosulfuron·atrazine,and all the M. aquaticum L. died 14 d after treatment. Atrazine was the best herbicide to control Gramineae weeds,followed by nicosulfuron·atrazine,and mesotrione·nicosulfuron·atrazine. The study on the application of field herbicide found that four herbicides including atrazine,mesotrione·nicosulfuron·atrazine,nicosulfuron·atrazine and bentazon had better control effect on weeds. The best herbicide for flax field was MCPA-Na + clethodim,followed by MCPA-Na and MCPA-Na + quizalofop-p-ethyl. The optimized herbicides and combinations had no harmful effects on the growth of corn and flax.

Evaluation of Preemergence Herbicides for Crop Safety and Weed Control in Safflower

Weed management in safflower (Carthamus tinctorious L.) is a major challenge for growers due to very limited herbicide options available, particularly for broadleaf weed control. Field experiments were conducted at the Montana State University Southern Agricultural Research Center (MSU-SARC) near Huntley, MT in 2015 and 2016 to evaluate preemergence (PRE) soil-residual herbicides for crop safety and season-long broadleaf weed control in safflower. Among all herbicide programs tested, only sulfentrazone (105 g·ai·ha-1) alone or with pendimethalin (1064 g·ai·ha-1) caused 4% to 12% early-season visible injury to safflower, although the injury was not evident beyond 30 DAT. Sulfentrazone alone or with pendimethalin and pyroxasulfone (59 g·ai·ha-1) with pendimethalin had a season-long residual activity on kochia [Kochia scoparia (L.) Schrad] and Russian-thistle (Salsola tragus L), with 89% to 99% control at 60 DAT, and up to 98% reduction in weed density compared with dimethenamid-P (213 g·ai·ha-1) and S-metolachlor (433 g·ai·ha-1) at 65 DAT. Pyroxasulfone (59 or 118 g·ai·ha-1) alone or dimethenamid-P with pendimethalin provided a moderate to good control (65% to 79% at 60 DAT) of kochia and Russian-thistle. However, the end-season control of kochia or Russian-thistle was inadequate ( S-metolachlor alone program. Safflower grain yield with sulfentrazone alone or with pendimethalin, pyroxasulfone alone or with pendimethalin, and dimethenamid-P with pendimethalin averaged 3559 kg·ha-1, which was 195% higher compared with the nontreated check. In conclusion, sulfentrazone and pyroxasulfone or dimethenamid-P in combination with pendimethalin will be effective PRE herbicide programs for kochia and Russian-thistle control in safflower.

Differential Susceptibility of <i>Conyza bonariensis</i>Biotypes to Glyphosate and ALS-Inhibiting Herbicides in Argentina

The aim of this study was to compare control of three stages biotypes (rosette, bolting, and repro- ductive stage) of Conyza bonariensis glyphosate susceptible biotype (S) and tolerant biotype (T) to glyphosate with glyphosate and mixtures of acetolactate synthase (ALS)-inhibiting. For glyphosate, the dose-response curves confirmed that injury of the biotype T relative to biotype S was signifi- cantly lower for both rosette and bolting stages. Resistance index (RI) for this herbicide was approximately 4 for both weed stages. At bolting, for both biotypes doses much higher than the recommended dose were required. For acetolactate synthase (ALS)-inhibiting herbicides, at the rosette stage, control of both biotypes was excellent with doses significantly lower than the recommended rate. All herbicides within this group showed a very low I50 relative to the recommended rate. These results indicate that biotypes difficult to control with glyphosate at the rosette and bolting stage may be controlled using acetolacte synthase (ALS)-inhibiting herbicides. Control for the reproductive stage was poor. A management program based on the combination of glyphosate with pre- and post-emergence acetolactate synthase (ALS) herbicides may be effective to control the weed.

Effects of Different Herbicides on Weed Control in Alfalfa Field

[Objectives]The paper was to systematically study the technology of weed control in alfalfa field.[Methods]Reviving alfalfa field and newly sown alfalfa field after emergence were selected,and the effects of different herbicides on weed control and alfalfa yield were discussed.[Results]The optimal herbicides after alfalfa reviving were 5%imazethapyr and 10%imazethapyr,and the optimal dosages were 1.5 and 1.05 L/hm 2,respectively.The optimal herbicides after emergence of newly born alfalfa were 5%imazethapyr and 10%imazethapyr,and the optimal dosages were 1.5 and 0.75 L/hm 2,respectively.[Conclusions]This study will provide a technical support for high quality production of alfalfa.

Effects of Different Herbicides on Weed Control,Agronomic Characters and Grain Quality of Coix lacryma-jobi L.

[Objectives]The paper was to study the effects of different herbicides on weed control,agronomic characters and grain quality of Coix lacryma-jobi L.[Methods]Six commonly used herbicides were selected for the trial,including atrazine SC,butachlor SC,monosulfuron WP,MCPA-starane EC,clopyralid AS and tribenuron-methyl WP.[Results](i)Atrazine,butachlor and monosulfuron had no chemical injury to C.lacryma-jobi L.,while clopyralid caused slight chemical injury.(ii)The fresh weight control effects of atrazine,butachlor and monosulfuron on weeds increased first and then decreased.The initial control effect of MCPA-starane and clopyralid reached more than 90%;the control effect of monosulfuron increased gradually in the late stage,reaching 97%at 60 d post spraying,and the overall control effect was optimal.(iii)Compared with manual weeding,herbicides had no significant effect on plant height of C.lacryma-jobi L.However,compared with no weeding,other herbicides except tribenuron-methyl inhibited plant growth to a certain extent.Herbicides had different effects on main stem diameter,tiller number per plant and grain number per plant of C.lacryma-jobi L.(iv)Different herbicides had no significant effect on 100-grain weight,but had significant effect on yield.(v)Compared with manual weeding,atrazine,butachlor and clopyralid decreased the protein content of C.lacryma-jobi L.,and the use of atrazine,butachlor,monosulfuron,MCPA-starane and tribenuron-methyl decreased the fat content of C.lacryma-jobi L.;butachlor and MCPA-starane decreased the glycerol trioleate content of C.lacryma-jobi L.Compared with no weeding,chemical herbicides had no significant effect on the protein content,while atrazine decreased the fat content,and butachlor and MCPA-starane decreased the glycerol trioleate content of C.lacryma-jobi L.[Conclusions]The use of herbicides significantly increases crop yield compared with no weeding,but has an impact on agronomic characters and grain quality.

Agronomic Efficiency of Herbicide Tolerant Crops in Peninsular India——A Review

Crops made resistant to herbicides by biotechnology are being widely adopted in various parts of the world and several herbicide resistant crops have become available in many countries for commercial cultivation.But in India,the technology of herbicide tolerant crops is in initial stage of field evaluation.Hence,field trials have been carried out to evaluate and consolidate the agronomic advantages of herbicide tolerant transgenic cotton and maize.Herbicide tolerant stacked traits of maize and cotton have been evaluated under Bio-safety Research Level(BRL I)as confined field trials for its agronomic efficiency on weed control and enhanced crop productivity at Tamil Nadu Agricultural University(TNAU),Coimbatore and Punjab Agricultural University(PAU),Ldhiana for many years.In both crops,potassium salt formulation of glyphosate was sprayed at different doses(900,1,350,1,800,2,700,3,600 and 5,400 g a.e./ha twice at 25 days after sowing(DAS)and 60 DAS in cotton and 900,1,800 and 3,600 g a.e./ha at 25 DAS in maize).Evaluation was made on weed control efficiency,phyto-toxicity on crops,yield and economics and carry over effects on the succeeding crops.Application of glyphosate at 2,700 g a.e./ha recorded lower weed density,dry weight and higher weed control efficiency(WCE)in cotton.Post-emergence(POE)glyphosate at 900,1,800 and 3,600 g a.e./ha registered lower weed density,dry weight and higher WCE in transgenic Hishell and 900 M Gold and in 30V92 and 30B11 corn hybrids.Post-emergence application of glyphosate in transgenic maize hybrids did not affect the germination percent,vigour and yield of succeeding green gram in the transgenic maize trials and sunflower,soybean and pearl millet in cotton trials.Phytotoxicity symptoms were not observed in cotton with glyphosate at lower doses viz.,900,1,350,1,800 and 2,700 g a.e./ha.Higher doses viz.3,600 g a.e./ha and 5,400 g a.e./ha were noticed with phytotoxicity symptoms at early stages of herbicide application.Glyphosate applied at 900,1,350,1,800 and 2,700 g a.e./ha recorded more number of bacteria,fungi and actinomycetes compared to atrazine treatments.Higher grain yield was recorded with POE application of glyphosate at 900,1,800 and 3,600 g a.e./ha in Hishell and 900 M Gold transgenic hybrids and higher net return and benefit cost ratio were recorded in glyphosate at 1,800 g a.e./ha in transgenic 900 M Gold in all the four seasons.Post-emergence application of glyphosate at 900 g a.e./ha and 1,800 g a.e./ha registered higher grain yield in transgenic 30V92 and 30B11 corn hybrids.In maize and cotton transgenic crops,post-emergence weed management with glyphosate proved to be the better management option for the control of weeds.

Application Effects of Several Herbicides in Spring Proso Millet Area in Northern Hebei Province

According to the ecological environment and current status of weeds in northern Hebei Province,five herbicides were screened out to test weed control efficacy and crop safety. The result showed that Gaolaotou was more economic and effective when spraying in soil on the sowing day at the dose of 2 250 m L/hm;.

几种除草剂对麦田阔叶杂草的防除效果

为明确几种除草剂对小麦田阔叶杂草的防除效果及对小麦的安全性,于返青期采用茎叶喷雾法,选取30%氰草津SC、10%唑嘧磺草胺SC、40%砜吡草唑SC、86%2甲4氯异辛酯EC+480 g/L灭草松AS、16%吡酰草·双氟草SC、5%双氟磺草胺OD、28.8%氯氟吡氧乙酸EC等7种药剂进行大田药效试验,测定其对猪殃殃、播娘蒿、荠菜等杂草的防除效果。结果表明,86%2甲4氯异辛酯EC+480 g/L灭草松AS、16%吡酰草·双氟草SC对总杂草的防效最好,药后45 d鲜重防效分别为93.05%和95.65%。30%氰草津SC、40%砜吡草唑SC对杂草的防除效果较差,药后45 d鲜重防效分别为51.51%、42.58%,但对于以葎草为主的延迟出土类杂草有较好的封闭效果。28.8%氯氟吡氧乙酸EC、86%2甲4氯异辛酯EC+480 g/L灭草松AS处理的小麦有药害产生,可能与施用苯醚甲环唑防治病害有关。其他处理对小麦生长无明显不良影响。可见,这7种除草剂对阔叶杂草防效的差异较大。相比其他单剂,86%2甲4氯异辛酯EC 387.0 g/hm^(2)+480 g/L灭草松AS 720.0 g/hm^(2)、16%吡酰草·双氟草SC 120.0 g/hm^(2)对各种杂草表现出优异的防效,在小麦返青期茎叶喷雾处理防除一年生阔叶杂草有较为良好的应用前景。

5种播前除草剂对橡胶草田的杂草防效及安全性评价

为筛选出适用于橡胶草田的播种前除草剂,以精异丙甲草胺(A1)、乙草胺(A2)、氟乐灵(A3)、二甲戊灵(A4)、仲丁灵(A5)5种除草剂推荐剂量为对照,设置不同剂量梯度[推荐用药量的0.4倍(B1)、0.6倍(B2)、0.8倍(B3)、1.0倍(B4)、1.2倍(B5)],分别在播种前5 d(C2)、10 d(C3)、15 d(C4)、20 d(C5)和播种当天(C1)进行土壤封闭处理,调查不同处理的封闭除草效果、相对出苗率及橡胶草出苗后的不同生长指标,并基于熵权赋值的DTOPSIS法对除草剂的杂草防效和安全性进行综合评价。结果表明,影响橡胶草田杂草防效和相对出苗率的因素主次顺序为除草剂种类>喷施时间>用药量,A3B3C5、A3B2C4处理的效果较好,即播种前20 d喷施480 g/L氟乐灵乳油(EC)120 mL/667 m^(2)和播种前15 d喷施480 g/L氟乐灵EC 90 mL/667 m^(2),对橡胶草田杂草防控效果综合排名靠前,对杂草的株防效分别为72.14%、86.05%,橡胶草相对出苗率分别为144.85%、95.15%。因此,建议采用480 g/L氟乐灵EC作为橡胶草田的优选土壤封闭除草剂,具体的施药量和施药方式有待进一步优化,研究结果可为橡胶草田杂草防控提供参考,以促进橡胶草产业化种植。

不同除草剂对豌豆田杂草的防除效果评价

杂草严重影响豌豆产量和品质,制约豌豆产业发展。为了筛选安全、高效的除草剂,选用3种芽前土壤封闭除草剂和6种苗后茎叶处理除草剂,在大田试验条件下进行作物安全性及杂草防除效果评价。结果显示,480 g/mL氟乐灵乳油和460 g/mL 2-甲-灭草松可溶液剂防效较好,施药后30 d株防效分别为76.88%、64.52%,施药后60 d株防效分别为75.86%、66.98%,鲜重防效分别79.59%、71.43%。24%乙氧氟草醚乳油对豌豆产生轻微药害;250 g/mL氟磺胺草醚水剂药害较重,严重抑制豌豆生长,应慎用。建议豌豆田杂草防除优先选用480 g/mL氟乐灵乳油和460 g/mL 2-甲-灭草松可溶液剂。

植保无人机喷施封闭除草剂对稻田杂草的防效研究

为探究植保无人机喷施除草剂对直播稻田杂草防效,采用50%丁草胺乳油、26%噁草酮悬浮剂、350 g/L异噁草松微囊悬浮剂、300 g/L丙草胺乳油4种封闭除草剂,在飞行高度2 m和3 m,用水量22.5、45.0 L/hm^(2)条件下设置不同处理,考察播前施药结合水层管理及播后干封对水稻安全性及对直播稻田不同种类杂草的防除效果。结果表明,26%噁草酮悬浮剂2个用水量处理的成苗率和苗高显著低于其余处理,播后30 d各处理水稻分蘖数均显著高于空白对照,各处理5株苗茎基宽与空白对照无差异。药后15 d,3种除草剂供试浓度下高用水量处理对稗草、千金子、多花水苋、异型莎草等杂草的防效均优于低用水量;播前水封与播后干封效果整体上差异不大。药后40 d,整体上各处理防效均降低,26%噁草酮悬浮剂、350 g/L异噁草松微囊悬浮剂在高用水量时对稗草的株数防效显著优于低用水量,3种药剂在高用水量时对千金子的株数防效均显著高于低用水量,鲜重防效与株数防效趋势基本一致。3种药剂不同飞防参数下对异型莎草和多花水苋的防效有差异,且效果较差。同一药剂在用水量45 L/hm^(2)和飞行高度3 m时对不同杂草的防效优于用水量22.5 L/hm^(2)和飞行高度2 m处理。不同除草剂对不同种类杂草的防效存在差异,高用水量播前施药结合水层管理对不同杂草的防效均优于播后干封处理。后期应适时进行茎叶处理,以提升施药对田间杂草的治理效果。

不同土壤处理除草剂对棉田杂草防除效果及安全性

为筛选出适宜本地区土壤处理的除草剂。通过大田小区试验,采用土壤封闭处理,对比分析了7种土壤处理除草剂对棉花安全性和杂草防除的效果。结果显示,与对照相比,不同药剂处理对‘冈棉11号’出苗率和第一果枝结位均没有显著性差异,但鲜重、株高和果枝数有增加趋势,表明试验药剂对棉花安全。田间药效结果显示,复配剂50%扑草净可湿性粉剂(WP)+33%二甲戊灵乳油(EC)、50%扑草净WP+960 g/L精异丙甲草胺EC和50%扑草净WP+50%乙草胺EC对禾本科和阔叶杂草均具有较好防效,45 d平均鲜重防效分别为83.32%、84.08%、80.57%,与单剂处理均存在极显著差异,且持效期较长,建议3种复配剂作为土壤处理除草剂用于棉田杂草防除。

42%精异丙甲草胺·异噁唑草酮·莠去津悬乳剂对玉米田一年生杂草的防除效果

为了明确玉米田土壤封闭的三混除草剂42%精异丙甲草胺·异噁唑草酮·莠去津悬乳剂在不同剂量处理下对杂草的防效和安全性,采用随机区组试验方法设计田间药效试验。结果表明,42%精异丙甲草胺·异噁唑草酮·莠去津悬乳有效成分用量1 890~2 205 g·hm^(-2)在玉米播后苗前施用,对玉米田主要杂草稗草、藜、本氏蓼、苘麻等杂草均有较好效果。施药后40 d,对试验玉米田杂草总草的株数防效为86.8%~95.0%,鲜重防效为88.9%~96.5%。各个剂量处理后的20 d和40 d及抽雄期,玉米均未出现药害,同时对其他非靶标生物无影响。各药剂处理区与空白对照相比玉米产量均增产显著,增产率为74.4%~81.4%。说明土壤封闭除草剂42%精异丙甲草胺·异噁唑草酮·莠去津悬乳剂在对玉米安全的同时对杂草具有较好的防效。用于玉米田一年生杂草的防除时,适宜的施药剂量为4 500~5 250 mL·hm^(-2)(有效成分用量1 890~2 205 g·hm^(-2))。

新疆荒漠绿洲区大麦田阔叶杂草化学防除药效评价

【目的】筛选对大麦田阔叶杂草具有较好防效的除草剂,为荒漠绿洲生态区安全高效应用除草剂提供依据。【方法】采用随机区组的方法,调查各药剂处理小区的杂草株数和地上部分鲜质量,评价供试药剂对大麦田阔叶杂草的防除效果及安全性。【结果】药后50 d,20%双氟·氟氯酯WG 19.50 g/hm^(2)、10%双唑草酮OD 37.50 g/hm^(2)、200 g/L氯氟吡氧乙酸EC 210.00 g/hm^(2)、22%氟吡·双唑酮OD 165.00 g/hm^(2)、50%2甲·氯·双氟SC 450.00 g/hm^(2)、87.5%2,4-滴异辛酯EC 577.50 g/hm^(2)、25%辛酰溴苯腈EC 562.50 g/hm^(2)和75%苯磺隆WG 22.50 g/hm^(2)对阔叶杂草灰绿藜和卷茎蓼的株防效和鲜质量防效较好,防效分别为90.87%~96.02%和94.15%~98.08%,各处理株防效和鲜质量防效之间均无显著性差异。【结论】20%双氟·氟氯酯WG、10%双唑草酮OD、200 g/L氯氟吡氧乙酸EC、22%氟吡·双唑酮OD、50%2甲·氯·双氟SC、87.5%2,4-滴异辛酯EC、25%辛酰溴苯腈EC和75%苯磺隆WG可防除大麦田灰绿藜、卷茎蓼等阔叶杂草,且对大麦生长安全,可在大田合理轮换使用。