Adsorption characteristic of bensulfuron-methyl at variable added Pb^(2+) concentrations on paddy soils

The combined pollution of heavy metal Pb^2＋ and bensulfuron-methyl （BSM）, originating from chemical herbicides, in agroecological environments has become commonplace in southern China. The adsorption of BSM on three paddy soils in the presence of Pb^2＋ was examined using high-performance liquid chromatograph （HPLC）. Results indicated that adsorption of BSM could accurately be described by a Freundlich isotherm equation with correlation constant （R） 〉 0.98, irrespective of the presence of spiked Pb^2＋. Of the various factors influencing BSM sorption, soil pH appeared to be the most influential. The constant Kf of Freundlich isotherm equation tended to increase with increasing Pb^2＋ concentration in soil which indicated that the spiked of Pb^2＋ in paddy soils would promote the sorption of BSM. AGo of BSM in three paddy soils was less than 40 kJ/mol in all treatments, indicating the adsorption of BSM is mainly physical in nature. The elution of soil dissolved organic matter （DOM） enhanced the adsorption of BSM in paddy soils. The mechanisms involved in the promotion effects of the spiked Pb^2＋ on BSM adsorption might be the modified surface characteristics of paddy soil solids due to the soil acidification and the increase of soil organic matter concentration because of DOM binding.

Analysis of culturable and unculturable microbial community in bensulfuron-methyl contaminated paddy soils

To investigate the influence of bensulfuron-methyl(BSM)on culturable microbial quantities and unculturable microbial community structures,conventional and molecular biological methods were employed in five BSM treated soils with three replications,respectively. The results obtained with traditional culture-dependent methods showed that a low-level of BSM had slight and transient effects on culturable microorganisms;nevertheless,high concentration of BSM resulted in a dramatic decrease in bacterial colony fo...

Rapid degradation of bensulfuron-methyl upon repeated application in paddy soils

Rapid degradation of bensulfuron-methyl upon repeated application in paddy soils was studied. The results showed that the DT _ 50 of bensulfuron-methyl was reduced from 16 d to 9 d in soil with one-year bensulfuron-methyl application. Rapid bensulfuron-methyl degradation was happened to previously untreated soil by addition 5% rapid bensulfuron-methyl adapted soil and was inhibited following pre-treatment with broad-spectrum antibiotic chloramphenicol. In bensulfuron-methyl adapted soil mineralisation of 14 C labeled bensulfuron-methyl to 14 CO_2 occurred at a faster rate than with previously untreated soil. It was concluded that rapid bensulfuron-methyl degradation upon repeated application is probably linked to the adaptation of soil bacteria which can utilize bensulfuron-methyl as a source of carbon and energy.

Effect of Bensulfuron-Methyl on Growth of Chlorella pyrenoidosa

To study the growth effects of differing concentrations of bensulfuron-methyl on Chlorella pyrenoidosa and to evaluate the ecological risk, the effects of bensulfuron-methyl on the growth and the content change of chlorophyll and protein in Chlorella pyrenoidosa were studied through 96 h acute toxicity tests. Bensulfuron-methyl accelerated the growth of algae at lower concentrations （〈 1 mg L^-1） with content increase of chlorophyll or protein, and it inhibited the growth of algae at higher concentrations （〉 5 mg L^-1）. The content of chlorophyll or protein in algae cells reduced with the increasing concentration of bensulfuron-methyl, exhibiting the good concentration-effect relationship. The 96 h-EC50 of bensulfuronmethyl upon the algae was 15.7 mg L^-1 Bensulfuron-methyl has inhibiting effect on the growth of Chlorella pyrenoidosa and is low in toxicity.

Research Progress in Microbiological Degradation of Bensulfuron-Methyl Herbicide

This paper reviewed the strategies and methods of screening for microorganisms having strong ability bensulfuron-methyl （BSM）, and discussed BSM degradation pathways and factors affecting its microbial metabolism prospected the research emphasis in the future to remove Finally, it

Effects of temperature and pH on the inhibition of Bensulfuron-Methyl(BSM)

Bensulfuron-Methyl(BSM)is a highly active sul-fonylurea herbicide that effectively controls most an-nual and perennial broadleaf or sedge weeds in paddyfield.However,the activity of BSM is affected byseveral evironmental factors.Using corn seedlings asmaterial,we found that under different temperatures

10%环庚草醚·苄嘧磺隆可湿性粉剂防除水稻抛秧田杂草效果

通过田间试验研究了10%环庚草醚.苄嘧磺隆可湿性粉剂(江苏镇江农药厂生产)对水稻抛秧田杂草的控制效果和对水稻产量的影响,为水稻抛秧田草害的化学防控提供依据。结果表明,10%环庚草醚.苄嘧磺隆可湿性粉剂对水稻抛秧田的稗草、矮慈菇、鸭舌草、水马齿、四叶萍等均具有良好的防治效果,有效成分用量为30～60 g/hm2的10%环庚草醚.苄嘧磺隆WP综合鲜重防效和综合密度防效分别为93.46%～97.52%、95.90%～98.21%,显著优于对照药剂10%环庚草醚EC和10%苄嘧磺隆WP。施用10%环庚草醚.苄嘧磺隆可湿性粉剂后,增产效果总体优于对照药剂,在水稻抛秧田具有良好的推广前景。

桉树脑类除草剂环庚草醚的合成

α－蒎烯与硫酸反应，给出１，４－桉树脑。再与锂、１，３－丙二胺反应，得萜品－４－醇，再气化后，与α－甲基氯苄反应得到环庚草醚。

几种助剂对苄嘧磺隆除草活性的增效作用研究(英文)

[ Objective] The aim was to select the best additives of bensulfuron-methyl. [ Method ] Taking radish as the testing plant, the synergistic effect of five common additives including Span 60, methyl olelate, silicone oil I, Tween 20 and detergent on the herbicidal activities of bensulfuron-methyl were tested in the la- borotory. [ Results ] The effects of the mixture of various additives and bensulfuran-methyl on relative stem control effect of radish, relative inhibition rate against stem length, relative inhibition rote against abeveground fresh weight, relative inhibition rote aginst root length and root fresh weight were studied, and the results showed that Span 60 and methyl olelate had stronger synergistic effect on the herbicidal activities of bensulfuron-methyl, and the synergistic effect of detergent was the weakest. [ Conclusion ] Span 60 and methyl olelate could be used as the synergistic agents of bensulfuron-methyl, and the study could provide references for se- lecting the additives of bensulfuron-methyl.

Effects of pesticides on soil biochemical characteristics of a paddy soil

The impact of triazophos, bensulfuron-methyl, chlobenthiazone on soil biochemical characteristics in a paddy soil under controlled moisture(flooded soil) and temperature(25℃) condition was studied. The electron transport system(ETS)/dehydrogenase activity displayed a negative correlation with triazophos, bensulfuron-methyl, chlobenthiazone concentrations, and the activity decreased as the concentration of the pesticides increased. The higher doses, 5 and 10 field rates, of triazophos, bensulfuron-methyl, chlobenthiazone significantly inhibited ETS activity, while lower rates failed to produce any significant reducing effect against the control. The relative toxicity of triazophos, bensulfuron-methyl, chlobenthiazone in decreasing the ETS activity was in the order: triazophos > chlobenthiazone > bensulfuron-methyl, irrespective of the rates of application. Triazophos, bensulfuron-methyl, chlobenthiazone caused an improvement in the soil phenol content and it increased with increasing concentration of triazophos, bensulfuron-methyl, chlobenthiazone. Triazophos, bensulfuron-methyl, chlobenthiazone incorporation did not produce any significant change in soil protein content. The response of biomass phospholipid content was nearly similar to ETS activity. The phospholipid content was decreased with the addition of triazophos, bensulfuron-methyl, chlobenthiazone in the order of triazophos > chlobenthiazone > bensulfuron-methyl; and the toxicity of applied amount was in the order: 10 FR(field rate) > 5 FR > 1 0 FR > 0 5 FR > control.

环庚草醚气相色谱分析方法

采用气相色谱法， ５％ ＯＶ— １０１填充柱和氢火焰离子化检测器，以邻苯二甲酸二丙酯为内 标，对环庚草醚进行定量测定。该方法简便、快速、准确、实用。标准偏差为０．７３，变异系数为 ０．８１％，回收率为９８．９９％～１００．５１％。

环庚草醚防除稻田杂草的试验研究

在秧苗移载后５天，每公顷用１０％环庚草醚乳油３００毫升，或１０％环庚草醚乳油１５０毫升＋１０％苄嘧黄隆可湿性粉剂２２５克，用毒土法撒施，对水稻本田中的稗草、牛毛毡、异型莎草、鳢肠、丁香等杂草的防效可稳定在９０％以上，且在此剂量下，对水稻及下茬麦子是安全的。

水稻除草剂Argold

Argold 正在评价作为水稻田插秧后使用的除草剂,现已表明它对许多主要的杂草有较好的防除效果,并已显示出对所适作物的选择性。其化学名称:外-1-甲基-4(1-甲基乙基)-2-(2-甲基苯基甲氧基)-7-氧双环-(2,2,1)

苄·环庚除草剂开发与应用技术研究

近年来大面积推广水稻轻型栽培技术,水稻10—15天秧龄抛秧、地膜秧、工厂秧和直播田面积不断扩大,化除难度增大,草害问题突出,威胁严重。本研究以水稻小苗(抛秧)田和直播田杂草防除为目标,旨在研究开发新型除草剂的应用技术。研究结果表明:苄.环庚除草剂(商品名:谷旺)杀草谱广,对一年生稗草、千金子、异型莎草、丁香蓼、陌上菜、鸭舌草、节节菜等均有较好的防效,对多年生的矮慈姑、野荸荠也有明显的效果,在适时施用,方法适当的前提下,亩用10%苄.环庚可湿性粉剂40—50g,一次用药即能有效地控制水稻全生育期杂草的危害,综合防效达95%左右,且安全性好,农本比施用二氯苄、丁苄、苯苄、龙杀等除草剂降低四分之一,经济效益显著提高。

Adsor ption and Degradation of Bensu-lfuron-methyl in Paddy Field

This paper studied adsorption and deyradation of bensulfuron-methyl (BSM) by bioassay method. The results showed that adsorption rate of BSM increased with increasing organic matter content. Degradation velocity of BSM changed fast with pH inreasing and temperature decreasing. There were different degradation of BSM between in water and soil. BSM was degraded rapidly in initial period. Afterward the degradation of BSM was slow dow. With increasing organic matter content deyradation of BSM in water was faster than that in soil.

Expression of sulfur uptake assimilation-related genes in response to cadmium,bensulfuron-methyl and their co-contamination in rice roots

The responses of sulfur （S） uptake assimilation-related genes＇ expression in roots of two rice cultivars to cadmium （Cd）, bensulfuron-methyl （BSM） and their co-contamination （Cd＋BSM） were investigated by gene-chip microarray analysis and quantitative real-time PCR （QRT-PCR） technology. Treatments of Cd and Cd＋BSM induced expression of sulfate transporter and permease genes, and promoted sulfate uptake in rice roots. Cd＋BSM could alleviate Cd toxicity to cv. Fengmeizhan seedlings, probably due to Cd＋BSM promoting greater S absorption by seedlings. Cd and Cd＋BSM induced expression of sulfate assimilation-related genes, and thus activated the sulfur assimilation pathway. Cd and Cd＋BSM induced expression of phytochelatin synthase and metallothionein genes, and induced expression of glutathione S-transferases （GSTs）, glutathione synthase （GS） and S- containing antioxidation enzyme genes, which detoxified Cd2＋. It is suggested that （to cope with the toxicity of Cd, BSM and their co-contamination） the S uptake and assimilation pathway was activated in rice roots by increased expression of related genes, thus enhancing the supply of organic S for synthesis of Cd or BSM resistance-related substances.