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磺酰脲类除草剂在世界各地受到广泛应用,但其作用位点单一,杂草对其易产生抗药性.在贵州,磺酰脲类除草剂苄嘧磺隆、吡嘧磺隆应用至少有20年以上历史,为明确贵州稻田杂草眼子菜对磺酰脲类除草剂苄嘧磺隆、吡嘧磺隆的抗药性,指导农户合理用药,课题组采集贵州不同地区稻田杂草眼子菜鳞茎,采用《农药室内生物测定试验准则》的方法进行测定.试验结果表明:苄嘧磺隆、吡嘧磺隆对贵州稻田杂草眼子菜的防效较好,其鲜重防效在81％以上;所采样田块中眼子菜对苄嘧磺隆的IR值在1.00～7.53之间,对吡嘧磺隆的IR值在1.00～10.67之间.表明贵州稻田杂草眼子菜对磺酰脲类除草剂抗性水平不高,但部分田块已开始出现抗药性生态型眼子菜,且眼子菜对苄嘧磺隆、吡嘧磺隆两种药剂间存在着交互抗药性. 相似文献
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从2004年开始,延边地区稻田大量发生抗磺酰脲类除草剂苄嘧磺隆的抗药性生态型雨久花。为解析其抗药性突变机制,采用离体法测定了抗、感性雨久花乙酰乳酸合成酶活性。结果表明,抑制抗、感性雨久花乙酰乳酸合成酶活性50%的苄嘧磺隆剂量为253.44×10-7mol/L和2.80×10-7mol/L;抑制抗、感性雨久花乙酰乳酸合成酶活性50%的吡嘧磺隆剂量为1802.15×10-7mol/L和20.85×10-7mol/L。抗药性雨久花对苄嘧磺隆和吡嘧磺隆的抗性系数(RI50/SI50)值分别为90.6和86.5,并存在交互抗药性。确认抗药性突变系由其乙酰乳酸合成酶对磺酰脲类除草剂苄嘧磺隆、吡嘧磺隆反应钝化所致。 相似文献
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四种除草剂在水稻上的消解及残留规律研究 总被引：1，自引：0，他引：1
为研究四种水稻用除草剂(苄嘧磺隆、吡嘧磺隆、丙草胺、丁草胺)的消解及残留规律,建立了四种除草剂在土壤、糙米、稻壳中的分析检测方法:四种除草剂在各基质中三个添加水平的回收率均在70%-110%范围内,变异系数在1.5%-14.9%之间;基质标准曲线在0.01~1mg/kg的线性范围内,可决系数均在0.98以上,线性相关性良好,可满足检测要求。土壤检测结果显示按照推荐剂量和二倍推荐剂量施药10d后,四种除草剂的残留量均小于本方法定量限;四种除草剂最终残留量均小于糙米中最低残留限量,表明在水稻上按照推荐剂量使用这四种除草剂是安全的。 相似文献
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通过田间小区试验评价了前期筛选的几种适用“播喷同步”的封闭除草剂对水稻的安全性及对直播田杂草的防效, 明确了“播喷同步”技术与常规播后4 d封闭的差异, 以及施药时期×除草剂种类交互作用及对控草效果的影响, 优化水稻直播田杂草防控策略?试验结果表明, 播种当天(播喷同步)或播种后4 d(常规方法)喷施120 g/L噁草酮EC 360 g/hm2+10%苄嘧磺隆WP 30 g/hm2(有效剂量, 下同)?33%嗪吡嘧磺隆WG 74.25 g/hm2+300 g/L丙草胺EC 450 g/hm2?60%丁草胺EC 1 350 g/hm2+10%吡嘧磺隆WP 30 g/hm2?35%吡嘧·嘧草·丙OD 525 g/hm2?300 g/L丙草胺EC 450 g/hm2+10%苄嘧磺隆WP 30 g/hm2, 5组除草剂处理对直播稻均无可见药害, 各“播喷同步”处理的杂草防除效果不低于常规播后4 d用药; 同步喷施33%嗪吡嘧磺隆WG+300 g/L丙草胺EC防效最高, 药后35 d对禾本科?莎草科?阔叶草防效达到98.3%及以上; 水稻直播4 d后喷药, 水稻成苗率提高但 35 d 的禾本科杂草防效低, 33%嗪吡嘧磺隆WG+300 g/L丙草胺EC处理受喷药时间影响小; 复合双因子方差分析表明, 单一因子会对水稻安全性?杂草防效产生显著影响, 用药时期×除草剂种类交互对水稻安全性无显著影响, 对控草效果影响显著?因此, 直播田封闭除草剂宜尽早施药提高防治效果, 同时应选用安全高效的除草剂, 33%嗪吡嘧磺隆WG+300 g/L丙草胺EC处理, 可于播种当天到播种后4 d内用药, 保障直播田杂草防治效果的同时兼顾水稻安全? 相似文献
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<正>多年来,稻田常用除草剂单剂主要有丁草胺、乙草胺;防除阔叶草主要有苄嘧磺隆、吡嘧磺隆、二甲四氯等,杀草谱较单一。目前农村青壮年劳力外出务工多,留下耕作的大多是年长的农民,普遍文化程度不高,在除草剂使用中,方法不对路、不注意科学安全用药、田块耕耙不平等造成稻田除草剂药害。1稻田除草剂药害发生的原因据生产中调查,造成稻田药害的原因有: 相似文献
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磺酰脲类除草剂是应用较为广泛的农药之一,其在土壤中迁移、降解、转化和滞留等多个过程受其吸附、解吸行为的影响。本文以嗪吡嘧磺隆为研究对象,采用批量平衡法研究了其在8种不同类型土壤中的吸附、解吸附行为。结果表明:嗪吡嘧磺隆与土壤溶液接触4 h内为快速吸附阶段。Freundlich模型可较好地拟合嗪吡嘧磺隆在土壤中的等温吸附解吸过程,相关系数 (r) 值在0.9584~0.9973之间。8种土壤对嗪吡嘧磺隆的吸附能力均为弱,吸附常数 (Kf-ads) 在0.281~3.515之间。其中,以黑龙江白浆土对嗪吡嘧磺隆的吸附能力最强,且远高于其他土壤。除广西赤红壤外,嗪吡嘧磺隆在其他7种类型土壤中的滞后系数 (H) 均小于1,解吸过程存在滞后现象,存在潜在环境风险。单因素试验结果表明,嗪吡嘧磺隆在土壤中的吸附行为受腐殖酸的影响极显著 (P＜0.01),受pH值和Mn2 + 的影响显著 (P＜0.05),受高岭土和稻壳生物炭的影响不显著 (P＞0.05)。采用中心复合试验设计,建立了具有一定预测功能的嗪吡嘧磺隆在土壤中的吸附过程BP神经网络模型,并进行了验证,拟合结果较好。 相似文献
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建立了高效液相色谱-串联质谱检测糙米、稻壳和秸秆中氯吡嘧磺隆残留的分析方法。样品经乙腈和水提取,C 18吸附剂净化,多反应监测模式检测,外标法定量。结果表明,在0.01~2mg/L范围内,氯吡嘧磺隆的质量浓度与对应的峰面积间呈良好的线性关系,其相关系数为0.9997。在0.01~0.5mg/kg添加水平下,氯吡嘧磺隆在糙米中的平均回收率为95%~98%,相对标准偏差(RSD)为2%~4%。在0.05~5mg/kg添加水平下,氯吡嘧磺隆在稻壳和秸秆中的平均回收率为78%~87%,相对标准偏差(RSD)为1%~5%。氯吡嘧磺隆在糙米中的定量限(LOQ)为0.01mg/kg,在稻壳和秸秆中的定量限(LOQ)为0.05mg/kg。该方法简便、快速、准确。 相似文献
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A Cyperus difformis L accession from Chonnam province, Korea was tested for resistance to the sulfonylurea herbicide, imazosulfuron. The accession was confirmed to be resistant (R) and was cross-resistant to other sulfonylurea herbicides, bensulfuron-methyl, cyclosulfamuron and pyrazosulfuron-ethyl, the pyrimidinyl thiobenzoate herbicide, bispyribac-sodium, and the imidazolinone herbicide imazapyr, but not to imazaquin. Multiple resistance was tested using twelve herbicides with target sites other than acetolactate synthase (ALS). The R biotype could be controlled by other herbicides with different modes of action such as butachlor, carfentrazone-ethyl, clomeprop, dithiopyr, esprocarb, mefenacet, oxadiazon, pretilachlor, pyrazolate and thiobencarb, applied to soil at recommended rates. Several sulfonylurea herbicide-based mixtures can control both the R and S biotypes of C difformis, except sulfonylurea plus dimepiperate, molinate or pyriftalid, and pyrazolate plus butachlor. Although mixtures of sulfonylurea herbicides might be more effective, they should be avoided and used only in special cases. In terms of in vitro ALS activity, the R biotype was 1139-, 3583-, 1482-, 416-, 5- and 9-fold more resistant to bensulfuron-methyl, cyclosulfamuron, imazosulfuron, pyrazosulfuron-ethyl, bispyribac-sodium and imazapyr, respectively, than the S biotype. The in vivo ALS activity of the R biotype was also less affected by the sulfonylurea herbicides, imazosulfuron and pyrazosulfuron-ethyl, than the S biotype. Results of in vitro and in vivo ALS assays indicated that the resistance mechanism of C difformis to ALS inhibitor herbicides was primarily due to an alteration in the target enzyme, ALS. Greenhouse experiments showed delayed flowering and reduced seed production of the R biotype, which could possibly result in reduced fitness. This unusual observation needs to be confirmed in field situations. 相似文献
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Nine Monochoria vaginalis Pres1 accessions from Chonnam province, Korea were tested for resistance to the sulfonylurea herbicide, imazosulfuron, in whole-plant response bioassay. All accessions were confirmed resistant (R) to imazosulfuron. The GR50 (imazosulfuron concentration that reduced shoot dry weight by 50%) values of R accessions were 1112-3172 (accession #9) times higher than that of the standard susceptible (S) accession. Accession #9 exhibited cross-resistance to other sulfonylurea herbicides, bensulfuron-methyl, cyclosulfamuron and pyrazosulfuron-ethyl, but not to the imidazolinone herbicides, imazapyr and imazaquin. The R biotype could be controlled by other herbicides with different modes of action, such as mefenacet and pyrazolate, applied to soil at recommended rates. Foliar-applied herbicides, 2,4-D and bentazone, also controlled both the R and S biotypes. Sulfonylurea-based mixtures, except ethoxysulfuron plus fentrazamide, did not control resistant M. vaginalis. Rice yield was reduced 70% by resistant M. vaginalis that escaped pyrazosulfuron-ethyl plus molinate, compared with hand weeding in direct-seeded rice culture. In contrast, rice yield was reduced 44% by resistant M. vaginalis that survived the pyrazosulfuron-ethyl plus molinate treatment, compared with pyrazolate plus butachlor in transplanted rice culture. In vitro acetolactate synthase (ALS) activity of the R biotype was 183, 35, 130 and 31 times more resistant to imazosulfuron, bensulfuron-methyl, cyclosulfamuron and pyrazosulfuron-ethyl, respectively, than the S biotype. Imidazolinone herbicides, imazapyr and imazaquin had similar effect on in vitro ALS activity of the R and S biotypes. The in vivo ALS activity of the R biotype was also less affected than the S biotype by the sulfonylurea herbicides imazosulfuron and pyrazosulfuron-ethyl. Results of in vitro and in vivo ALS assays indicate that the resistance mechanism of M. vaginalis to sulfonylurea herbicides may be due, in part, to an alteration in the target enzyme, ALS. Since the level of resistance in the enzyme assay was much lower than that in the whole-plant assay, other mechanisms of resistance, such as herbicide metabolism, may be involved. 相似文献
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螺虫乙酯对大型溞的急性和慢性毒性效应 总被引：1，自引：0，他引：1
为评价新型季酮酸衍生物类杀虫剂螺虫乙酯(spirotetramat)对水生生物的生态危害,以大型溞Daphnia magna为研究对象,将其暴露于不同质量浓度的螺虫乙酯中,通过急性毒性试验、慢性毒性试验和子代染毒及恢复试验,研究螺虫乙酯对大型溞的急性和21 d慢性毒性效应。急性毒性试验结果表明,螺虫乙酯对大型溞的48 h-EC50值为46.55 mg/L。慢性毒性试验结果表明,经不同浓度螺虫乙酯暴露21 d后,4.7 mg/L浓度组在初次产溞数、母溞产溞总数和母溞产胎数上较对照都有显著减少,并显著延后了初次产溞的时间。经螺虫乙酯暴露后的F0代大型溞所产后代(F1代)对螺虫乙酯的耐药性降低,同时对F1代染毒组的初次产溞时间、初次产溞数和产胎数均有显著影响,但仅对F1代恢复组的体长有显著影响。综上所述,螺虫乙酯对大型溞具有一定的生殖毒性,并在一定程度上对大型溞的生长和繁殖能力具有抑制效应。 相似文献
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AbstractA study was carried out in sandy clay loam textured soil of Mymensingh, Bangladesh to evaluate weed control efficiency of pre-emergence herbicide pyrazosulfuron-ethyl either alone or in sequential application with post-emergence herbicide in transplanted rainy season rice under non-puddled strip-tilled (NPST) field condition and also to examine the residual effect of those herbicides on germination and growth of the subsequently grown wheat crop. Five treatment combinations of pyrazosulfuron-ethyl were tested against one weedy check and one weed-free check. The study revealed that NPST rice field was mostly infested by grass and sedge weeds and herbicide treatments offered a wide range of control (above 50% to 95%) on all types of weeds. Application of pyrazosulfuron-ethyl followed by (fb) orthosulfamuron fb butachlor plus propanil provided the most effective and economic weed control over two years of the study. Moreover, micro-plot bioassay study claimed germination and growth of subsequently grown wheat were not adversely affected by herbicides that were applied in rice. Therefore, application of pyrazosulfuron-ethyl followed by post-emergence herbicide could be effective and economic to control weeds in NPST rice under rice-wheat system, but proper rate and time of application should strictly be followed. 相似文献
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Evin Polat Akköprü 《Phytoparasitica》2018,46(4):511-520
The development, reproduction, and population growth parameters of cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), were studied on three different Cucumis sativus cultivars (Beith Alpha Bal?kesir, B.T. Bursaalpha, Beith Alpha MR,) under controlled conditions (25?±?1 °C, 65?±?5% RH, and a photoperiod of 16:8 (L:D) h. Life table parameters were estimated according to age-stage, two-sex life table method. Results indicated that the Bt Bal?kesir are favorable hosts for A. gossypii because of the shorter preadult developmental time, lower preadult mortality rate, and higher total fecundity on this cultivar. The intrinsic rate of increase (r?=?0.4214 d-1), the net reproduction rate (R0?=?51.80 offspring), and the finite rate of increase (λ?=?1.5242 d-1) values were higher on the Bt Bal?kesir. The effect of cucumber cultivars on the biology of A. gossypii was determined as significant and it was found that cv. Bt Bal?kesir was the most convenient cucumber cultivar in terms of the life cycle of A. gossypii. For an ecological and economic pest control, against aphids use of resistant or less favourable crop cultivars is considered one of the important components of integrated pest management. Therefore, results acquired might be used in pest management program that will be prepared for this aphid. 相似文献
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Resistance to sulfonylurea herbicides, including bensulfuron-methyl, pyrazosulfuron-ethyl, imazosulfuron and ethoxysulfuron, was discovered in naturally occurring populations of Lindernia micrantha D. Don in rice fields that had been treated with sulfonylurea-based herbicides for 3–7 consecutive years. The resistant biotype was approximately 80≈300 times more resistant than the susceptible one to the above four sulfonylurea herbicides. This is the second confirmed occurrence of herbicide resistance resulting from the use of sulfonylurea herbicides in Japan. Several herbicides with different modes of action, including pretilachlor, cafenstrole, bifenox, naproanilide, thiobencarb + simetryn + MCPB, MCPA-thioethyl + simetryn and cyhalofop-butyl + bentazone, effectively controlled the resistant biotype in pot trials. 相似文献
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Based on a recently discovered property of chloroacetamide herbicides—the inhibition of the incorporation of oleic acid into sporopollenin of Scenedesmus acutus—a rapid quantitative test was developed for chloroacetamide-type herbicidal activity. In this test, algal cells are incubated for 3 h with [14C]oleic acid, saponified and the lipids (including non-saponifiable ones) extracted and discarded. The radioactivity incorporated into the residual non-lipid fraction is determined, and inhibition of this incorporation is used as a marker of chloroacetamide-type activity. Twenty-two agrochemical compounds were screened in this assay, which was found to be very sensitive, a 50% inhibition being reached with submicromolar herbicide concentrations. It is specific to chloroacetamides and related amides, since all these herbicides tested were potent inhibitors, while other herbicides were not. Highest inhibition was shown by cafenstrole followed by butachlor, fluthiamid, metazachlor, alachlor, dimethenamid, metolachlor and mefenacet. For these herbicides (with the exception of butachlor) sensitivity in the test was positively correlated (r=0·984) with their phytotoxic effect on the alga. © 1998 SCI 相似文献
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Hyun-Young Cho 《Pesticide biochemistry and physiology》2005,83(1):29-36
The structural gene for glutathione S-transferase in Oryza sativa was successfully cloned from a cDNA library by the polymerase chain reaction method. The deduced amino acid sequence of this gene showed 44-66% similarity to the sequences of the class phi GSTs from Arabidopsis thaliana and Zea mays. This gene was expressed in Escherichia coli with the pET vector system and the gene product was purified to homogeneity by GSH-Sepharose affinity column chromatography. The expressed OsGSTF3-3 was a homo-dimer composed of 24 kDa subunit and its pI value was approximately 7.3. The OsGSTF3-3 was retained on GSH affinity column and its Km value for GSH was 0.28 mM. The OsGSTF3-3 displayed high activity toward 1-chloro-2,4-dinitrobenzene, a general GST substrate and also had high activities towards acetanilide herbicides, alachlor, and metolachlor. The OsGSTF3-3 was highly sensitive to inhibition by benastatin A and S-hexyl-GSH. From these results, the expressed OsGSTF3-3 is a phi class GST and seems to play an important role in the conjugation of the chloroacetanilide herbicides. 相似文献
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The development, reproduction and life table parameters of the cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) on four ornamental plants (Hibiscus rosa-sinensis L., H. syriacus L. (Malvaceae), Brugmansia aurea Lagerh., Cestrum nocturnum L. (Solanaceae)) were studied at 25 ± 2 °C, 60% ± 10% r.h., and 16 hours daily artificial light. Life table data were analyzed by using an age-stage, two-sex life table. The highest intrinsic rate of increase (0.2911 d-1), finite rate of increase (1.3380 d-1), net reproductive rate (258.0 nymphs/female) and gross reproduction rate (342.6 nymphs/female), as well as the shortest mean generation times (19.1 days) were obtained when the mealybug was reared on H. syriacus. 相似文献