探讨甘蔗螟虫的化学防治,为筛选高效的防治药剂提供科学依据.采用蔗茎浸渍法测定了噻虫嗪、杀虫单及其混配对黄螟幼虫的室内毒力.结果表明噻虫嗪和杀虫单复配表现出明显的增效作用,噻虫嗪与杀虫单比值为1∶18时增效作用最显著,共毒系数为133.43.根据最佳配比配制成3.8％颗粒剂进行防治甘蔗螟虫的田间试验,结果表明3.8％杀虫单·噻虫嗪颗粒剂制剂用量55、70 kg/hm2施药90天后的防效分别为80.1％、85.4％,可作为防治甘蔗螟虫替代农药.

The quantitative determination of MCPA-Na and ethoxysulfuron by HPLC with Hypersil C18 column at 236nm was described. The mobile phase was acetonitrile+water(60+40). The results showed that the standard deviation was 0.38%and 0.022%, the coefficient of variation was 0.94%and 1.42%, and the recovery was 98.1%~101.0%and 98.4%~101.5%.

25% mefenacet · ethoxysulfuron effervescent tablet was prepared and field experiment was carried out. The result showed that the formulation of 25% mefenacet · ethoxysulfuron effervescent tablet was mefenacet 24%, ethoxysulfuron 1%, SDS 2%, MF-5 3%, citric acid 13.5%, sodium bicarbonate 16.5%, dextrin 3%, magnesium stearate 2.5%, white carbon black 34.5%. The control effect of weeds in rice field was over 90% at the dosage 375~525g(a.i) per hectare, the same as 53% mefenacet · bensulfuron-methyl WP and 15% ethoxysulfuron WDG, and there was no difference between them.

In recent years, the sugarcane yield of Guangxi was increased, but the sugar rate was declining. In the case of ensuring the sugarcane yield and how to improve the sucrose content was one of the important subjects. This article aimed to summarize the sugarcane nutrition physiology, fertilization research status and the problems of sugarcane fertilization in Guangxi, then provided theoretical guidance for the measures of increasing productivity and sucrose content in Guangxi.

The aim of the present study was to determine the pre-emergence application of 30%mixed butachlor and oxyfluorfen EW at a.i. 360~900 g/hm2 on controlling weeds in sugarcane fields. The results showed good control effect on annual weeds in Gramineae and broad-leaved weeds after 30 and 60 days of spraying. The control efficacy of 30%mixed butachlor and oxyfluorfen EW at dosages of a.i. 450~540 g/hm2 were more than 86%. It was safe to sugarcane at such dosages.

Field test results showed that when 40% ametryn oil miscible flowable concentrated with 1440~1800a.i.g/ha was spayed on weed at 2~5 leaves stage in sugarcane field could have a good control on gramineae and broadleaf weed,and the integrated effect was over 90% for 40 days after spaying.In the same dosage condition,it had a better effect than flowable concentrate and wettable powder products.

The invention discloses a herbicide composition containing glyphosate, MCPA (2-methyl-4-chloro-phenoxyacetic acid) and carfentrazone-ethyl. The herbicide composition is characterized in that the pesticide active ingredients of the composition are glyphosate or salts thereof, MCPA or salts or esters thereof and carfentrazone-ethyl; based on the herbicide composition, the weight percent of the pesticide active ingredients is 31.1-85%, wherein the weight percent of the glyphosate or salts thereof is 30-70%, the weight percent of the MCPA or salts or esters thereof is 1-30%, the weight percent of the carfentrazone-ethyl is 0.1-20% and the balance is non-pesticide ingredients. The dosage forms of the herbicide composition are wettable powder, water dispersible granules, soluble powder, soluble granules, aqueous solutions, emulsion in water and microemulsion. The composition has the advantages that after compounding, the herbicide composition has obvious synergistic effects, expands the weed control spectrum, increases the weed control speed, obviously reduces the usage amount and numbers of use of herbicides and can be applied to controlling imperata cylindrica, Bidens pilosa, dicranopteris dichotoma, eleusine indica, erigeron canadensis and other weeds in arable lands and non-arable lands.

The effect of 15% ethoxysulfuron WG for weeds control in sugarcane field was evaluated.The results showed that the strain control effect of 15% ethoxysulfuron WG against Spermacoce latifolia(Aubl.),Ageratum conyzoides L.,Conyza Canadensis L.,Rhizoma Cyperi was 87.29%～97.16%,89.68%～98.75%,85.53%～95.47%,91.20%～99.73%,respectively.The control effect of fresh weight was 89.62%～98.19%,88.76%～98.17%,87.38%～94.60% and 92.30%～99.82%,respectivily.The product was safety to sugarcane.

The quantitative determination of acetochlor and oxyfluorfen by HPLC with Hypersil C18 column at 235nm was described.The mobile phase was acetonitrile+water(78+22).The results showed that the standard deviation was 0.0019% and 0.0017%,the coefficient of variation was 0.81% and 1.06%,and the recovery was 99.83%～101.68% and 97.27%～100.49%.

The 40% ametryn oil miscible flowable concentrate was prepared by screening some main adjuvants of the formulation such as dispersion medium,emulsifier,dispersing agents and thickener.Physical and chemical properties of the 40% ametryn oil flowable concentrate were determined.The preparation had no appearance of stratification and could disperse in water wel1,and its indexes were in line with the relevant standards of oil suspension.

[Objective]The technique of the preparation of 30% oxyfluorfen and acetochlor emulsion in water was researched.[Method]The method of 30% oxyfluorfen and acetochlor emulsion,in which the oxyfluorfen,acetochlor,emulsifier,solvent oil,antifreeze and anti-foaming agent was used as main raw material,and its formulation was optimized.And the parameter of the formulation was evaluated.[Re-sults]The best formulation consisted of 5.0% oxyfluorfen,25.0% acetochlor,15.0% solvent oil 200#,S-80 emulsifier 5.2%,602# emulsi-fier 2.8%,ethylene glycol 4.0%,antifoaming agents 0.3% and water.And the testing result of the formulation indicated the appearance,dispersion,emulsion stability,heat storage rate and decomposition rate of water met the specification required.[Conclusion]The technique of 30% oxyfluorfen acetochlor EW was relatively simple,with stable performance,reliable quality,low content of toxicity,easy storage and safe-ty utilization and also with good environmental compatibility,low cost and strong market competitiveness.

The study on the Rhizoma cyperi(Cyperus rotundus L.) in Manilagrass turfgrass with two sulfonylureas herbicide showed that the control effect of 25% flazasulfuron was 84.8% at the dosage of 5 g per 667 m2,and reached 98.8% at the dosage of 20 g per 667 m2.The control effect of 75% Trifloxysulfuron was 90.7% at the dosage of 2 g per 667 m2,and reached 100% at the dosage of 8 g per 667 m2.The control effect of 56% MCPA-Na was 49.4% at the dosage of 100 g per 667 m2.

[Aims] The research aimed to establish a HPLC method for the determination of MCPA-sodium,ametryn and diuron in 73% WP.[Methods] The HPLC conditions were C18 column,acetonitrile-water(0.1 mol/L KH2PO4,40∶60,by vol) as mobile phase,UV detection at 210 nm,and an external standard method.[Results] The linear correlations of MCPAsodium,arnetryn and diuron were 0.9997,0.9995 and 0.9998 respectively.The standard deviations were 0.19,0.25 and 0.22 respectively.The variation coefficients were 1.81,0.60 and 0.94% respectively.The average recoveries were 100.0,100.1 and 99.9% respectively.[Conclusions] The analytical method for determination of MCPA-sodium,ametryn and diuron in 73% WP at one column and one condition is simple,rapid and reliable.It′s a preferred method of analysis.

[Objective]The aim of the present study was to determine the efficiency of 73% mixed MCPA-Na,ametryn and diuron WP on controlling weeds in sugarcane field.[Method]Different herbicides(56% MCPA-Na SP 840 a.i.g/ha,80% ametryn WP 1440 a.i.g/ha,80% diuron WP 1440 a.i.g/ha) and their different concentrations(876,1314,1752 and 2628 a.i.g/ha) were used to control weeds in the sugarcane fields,with water as the control.The controlling effects were investigated after 20 and 40 d of spraying.[Result]The controlling effects of 73% MCPA-Na,ametryn and diuron WP on plant and fresh weight were higher than 90.00% after 20 and 40 d of spraying.The weedicide application @ 876-2628a.i.g/ha resulted in control of most of the monocotyledonous and dicotyledonous weeds in sugarcane field,and showed better controlling effects compared to spraying single dose of 56% MCPA-Na SP,80% ametryn WP and 80% diuron WP.[Conclusion]73% mixed MCPA-Na,ametryn and diuron WP @ 1314-1752 a.i.g/ha may be recommended to control weeds in sugarcane field.

Cyperus rotundus L.was a destructive weed in sugarcane field and caused serious damage to sugarcane production.Field plot experiment of four herbicides against Cyperus rotundus L.in sugarcane field was conducted.The result showed that XIANGSHAYIJIAN 56 %WP at the doses of 840 to 1680 a.i.g/hm2 had relatively good control effect on the 4-6 leaves of Cyperus rotundus L.and other broadleaves.After 45 days of application,its control efficiency against Cyperus rotundus L.was above 92.0 %,and it was safe to the sugarcane at the recommended rate of application.

The results of laboratory tests showed that the LC50 of abamectin 0.8% CS against Prodenia litura Fabricius,Pieris rapae(L.),Plutella xylostella(L.) was 27.72,1.69 and 0.85 mg/L,respectively,which was approximately equal to the toxicity of abamectin 0.8% EC.The persistence tests showed that the effectiveness of abamectin 0.8% CS was better than that of abamectin 0.8% EC,particularly during 1-14 d.Field trials indicated that,at the dosage of 14.4 g/hm2,the control efficacy of abamectin 0.8% CS was over 89% on day 7 and over 80% on day 14 after treatment,and the effectiveness lasted for about 14 d.

Through the screening test and the control effect test of technical,various pesticide adjuvant and filler,the best formulation of bensulfuron-methyl and mefenacet 15% EB from various pesticide adjuvant was screened.The optimized formulation was: bensulfuron-methyl 2%,pretilachlor 13%,SDS 2.5%,NNO 4%,citric acid 14.5%,sodium bicarbonate 16.5%,lactose 6%,magnesium stearate 2%,add compound fillers with m(silica white):(bentonite)=1:1 respectively up to 100%.The result of control effect in field indicated that the index of effervescent tablet corresponded to the requirement of pesticides.In the dosage of 180 a.i.g/hm2 to 225 a.i.g/hm2,the product had good effect in rice fields,and the effect was better than other kinds of herbicide,it had the value for popularization in business.

The present study was conducted to study the effect of chlorpyrifos cartap granule(8%) on controlling sugarcane borer under filed conditions.The pesticide terbufos granule(5%) @ 3.0 kg ai/ha was used as the control,and chlorpyrifos cartap granule(8%) was applied @ 2.0,2.5 and 3.0 kg active ingredients(ai)/ha in loose and uphill soil.The application of chlorpyrifos cartap granule(8%) resulted in over 75% control efficacy on sugarcane borer after applying 60 and 90 days,though it was quite similar to the control,there were no significant differences.On the basis of results obtained in this study,it is suggested that 8% chlorpyrifos cartap granules may be used to control sugarcane borer when applied @ 2.0-3.0 kg ai/ha at the time of planting for plant crop or loosening soil for ratoon crop.