Field Efficacy Trials of 1%Bifenthrin·thiamethoxam GR against Sweet Potato Weevil

[Objectives]The paper was to verify the field efficacy of 1%bifenthrin·thiamethoxam GR replacing organophosphorus GR against sweet potato weevil and its impact on the yield and quality of sweet potato.[Methods]A total of 4 field trials were conducted in Guangdong Province,including 1%bifenthrin·thiamethoxam GR applied at the doses of 3,4 and 5 kg/667 m^(2),and 3%phoxim GR applied at the dose of 4 kg/667 m^(2).[Results]1%Bifenthrin·thiamethoxam GR applied at the dose of 5 kg/667 m^(2)had excellent control effects on sweet potato weevil,with an average control effect of 77.60%,which was significantly higher than that of 3%phoxim GR applied at the dose of 4 kg/667 m^(2)(48.52%).And the average yield increase rate of sweet potato treated with 1%bifenthrin·thiamethoxam GR reached 24.79%,significantly higher than 12.37%in the control group.[Conclusions]1%Bifenthrin·thiamethoxam GR should be evenly distributed on the ridge surface near sweet potato within 5-7 d after planting,and the recommended dosage is 5 kg/667 m^(2),which will have good control effect on sweet potato weevil and increase the yield of sweet potato.

Effects of imidacloprid and thiamethoxam as seed treatments on the early seedling characteristics and aphid-resistance of oilseed rape

Seed treatments with the neonicotinoid insecticides imidacloprid and thiamethoxam were evaluated to determine whether the chemicals at effective concentrations for aphid control would influence the germination and early growth of oilseed rape,Brassica napus.Treatment with imidacloprid or thiamethoxam did not affect the cumulative germination rate,but significantly inhibited establishment potential by suppressing root system development in the cotyledon stage.However,these alterations in seedling development in the thiamethoxam-treated seeds appeared not to be detrimental as leaves developed;in contrast,for the seedlings with imidacloprid as seed treatment agent,a significantly decreased shoot/root ratio was still evident at the late two-leaf stage.After two leaves developed,chlorophyll content per leaf in the thiamethoxam treatment was significantly higher than that of the control,while chlorophyll content per leaf in the imidacloprid treatment remained close to that in the control.Most other parameters,i.e.,height,leaf area,weight of stem,leaf or root,and other growth indexes,between the treatments and the control showed no significant difference.Additionally,it was found that storage time of the treated seeds had a significant effect on cumulative germination rate.Treatment 30 d before planting significantly reduced germination relative to that of the control.All of the plants treated with neonicotinoids were shown to have significant anti-aphid characteristics that persisted until the end of the trial.

Control Effect Evaluation of 70% Thiamethoxam ZF against Ceratovacuna lanigera Zehntner and Baliathrips serratus Kobus on Sugarcane

[Objective] The paper was to provide scientific basis for popularization and application of 70% Thiamethoxam ZF. [Method] 70% Thiamethoxam ZF was selected and applied in the soil for controlling Ceratovacuna lanigera Zehntner and Baliathrips serratus Kobus. [ Result ] 70% Thiamethoxam ZF had good con-rol effect against C. lanigera and B. serratus. The optimum dosage of 70% Thiamethoxam ZF was 450 g/hm^2 （effective ingredients 315 g）. 70% Thiamethoxam ZF （ dosage per hm^2 ） mixed with the regular fertilizer （ dosage per hm^2 ） should be applied together in sugarcane planting and management from February to June. The control effects against C. lanigera and B. serratus were above 98.4% and 82.9% respectively. The actual yield and sugar content were increased by more than 34 290 kg/hm^2 and 6.8% respectively compared to blank control. [ Conclusion] 70% Thiamethoxam ZF was a new ideal pesticide with characteristics of sustained- release, long-lasting and low-toxic for controlling C. lanigera and B. serratus, and should be applied widely in the sugarcane planting area.

Quantification of Thiamethoxam in Rhizomes and Leaves of the Hedychium coronarium and Water and Soil by High-Pressure Liquid Chromatography

The linearity, stability, accuracy and inter-day precisions of the assay method were evaluated in water, soil and rhizomes and leaves of Hedychium coronarium of the Zingiberaceae family. Mato Grosso do Sul is a predominantly agricultural state in Brazil and has many rivers and permanent and seasonal lakes, in which the Hedychium coronarium, an aquatic plant, is found the swampy environments. The prepared samples were analyzed quantitatively by High Performance Liquid Chromatography with PDA and UV detection for the presence of thiamethoxam. The thiamethoxam was recovered from these samples at rates ranging from 81.16% - 99.93%. The coefficient of variation in the quantitative analysis of the thiamethoxam was under 5%. The linearity of the method was determined by linear regression. The analysis of the samples spiked with known amounts of analyte demonstrated that the response was proportional to the concentrations of the samples with determination coefficients of r2 = 0.9992 (water and soil) and r2 = 0.9990 (leaves and rhizomes) for the linear range of the analytical calibration curves of the samples. The detection limit was 0.36 μg.L-1 and quantification limit was 1.2 μg.L-1 for thiamethoxam. The method was considered sensitive for quantification of the thiamethoxam in water, soil and rhizomes and leaves of Hedychium coronarium.

25%阿克泰(Thiamethoxam)可分散性粒剂防治烟粉虱试验初报

采用25％阿克泰（Thiamethoxam）可分散性粒剂4000～8000倍液进行移栽后喷雾和采用阿克泰WG2000～4000倍液进行移栽前苗期灌根处理，对番茄烟粉虱的防治效果均明显好于对照药剂，表明阿克泰WG对烟粉虱具有较高活性。试验结果表明，阿克泰WG对烟粉虱的若虫也具有较好的杀伤效果。施用阿克泰WG对番茄植株安全。

A nano-delivery system expands the insecticidal target of thiamethoxam to include a devastating pest,the fall armyworm

Nano-delivery systems have been applied to deliver various synthetic/botanical pesticides to increase the efficiency of pesticide use and reduce the volumes of pesticides applied.Previous studies have supported the hypothesis that the nanocarriers can help expand the insecticidal target of pesticides to include non-target pests.However,the potential mechanism underlying this interesting phenomenon remains unclear.Herein,a widely applied star polycation(SPc)nanocarrier was synthesized to construct a thiamethoxam(TMX)nano-delivery system.The SPc-based delivery system could promote the translocation of exogenous substances across the membrane of Sf9 cells,increase the cytotoxicity of TMX against Sf9 cells by nearly 20%,and expand the insecticidal target of TMX to include Spodoptera frugiperda(the fall armyworm),with a 27.5%mortality increase at a concentration of 0.25 mg/mL.Moreover,the RNA-seq analysis demonstrated that the SPc could upregulate various transport-related genes,such as Rab,SORT1,CYTH,and PIKfive,for the enhanced cellular uptake of TMX.Furthermore,enhanced cell death in larvae treated with the TMX-SPc complex was observed through changes in the expression levels of death-related genes,such as Casp7,BIRC5,MSK1,and PGAM5.The SPc-based nano-delivery system improved the cellular uptake of TMX and expanded its insecticidal target by adjusting the expression levels of death-related genes.The current study mainly identified the transport and cell death genes related to nanocarrier-based insecticidal target expansion,which is beneficial for understanding the bioactivity enhancement of the nano-delivery system.

70%噻虫嗪种子处理可分散粉剂拌种对大麦蚜虫的防治效果及增产作用

为了探索防治大麦蚜虫的科学有效措施,选用保山市大面积推广的二棱品种“保啤麦28号”,每10 kg种子分别用20、30、40 g 70%噻虫嗪种子处理可分散粉剂拌种防治蚜虫。结果表明:不同用量的70%噻虫嗪种子处理可分散粉剂拌种能有效抑制蚜虫对大麦的危害。大麦拔节期前,防效均达100%;大麦孕穗期至抽穗扬花期,防效为72.30%~95.70%;大麦灌浆期,防效为33.60%~80.04%;大麦乳熟期,防效为14.20%~49.44%,防效随着用量的增加而增加,且持效期更长;每10 kg种子用药30、40 g防效最佳,与每10 kg种子用30 mL的30%噻虫嗪悬浮种衣剂拌种防效相近。药剂拌种对大麦还具有增产作用,增产率为8.6%~16.9%。建议在大麦生产中,根据当地蚜虫发生规律选择不同用量、不同剂型的杀虫剂拌种防治大麦蚜虫,综合考虑防效、成本和用量,达到节本、增效的目的。

红螯螯虾幼虾对4种水稻农药耐受性研究

为了解稻田常用的生物农药或杀虫剂对红螯螯虾大规格幼虾的毒性效应,测定了中生菌素、氯虫·噻虫嗪、噻唑锌和井冈霉素A对其的急性毒性反应。结果表明:4种农药对红螯螯虾大规格幼虾96 h半致死浓度分别为19.66、1.65、1132.83、2092.07 mg/L。安全浓度分别为5.65、1.27、260.40、248.11 mg/L,根据耐受性和行为特征观察发现,4种药物对于4 cm左右的红螯螯虾幼虾的毒性大小依次为氯虫·噻虫嗪>中生菌素>噻唑锌>井冈霉素A,根据国家标准(GB/T16310.5—1996),噻唑锌和井冈霉素A对于4 cm红螯螯虾幼苗属于无毒农药,中生菌素属于微毒农药,而氯虫·噻虫嗪为中毒农药。本试验明确了红螯螯虾幼虾对水稻常用农药的耐受性,为红螯螯虾-水稻综合种养过程中的病害防治工作提供参考。

布地格福吸入气雾剂治疗稳定期中重度慢性阻塞性肺疾病患者的临床研究

目的探讨布地格福吸入气雾剂治疗稳定期中重度慢性阻塞性肺疾病(COPD)的临床疗效和安全性。方法选取2020年8月至2021年8月于莆田学院附属医院呼吸与危重症医学科就诊的123例稳定期中重度COPD患者作为研究对象,随机分为治疗组(n=60)与对照组(n=63)。对照组给予布地奈德福莫特罗粉吸入剂+噻托溴铵粉吸入剂治疗,治疗组给予布地格福吸入气雾剂治疗。比较两组治疗前后第1秒用力呼气容积占预测值百分比(FEV_(1)%Pred)、第1秒用力呼气容积占用力肺活量比值(FEV_(1)/FVC)、改良版英国医学研究委员会呼吸困难问卷(mMRC)、COPD患者自我评估测试(CAT)和圣乔治呼吸问卷(SGRQ)评分、6 min步行试验(6MWT)、急性发作次数、药物不良反应情况。结果治疗后,两组FEV_(1)%Pred、FEV_(1)/FVC均高于治疗前,6MWT长于治疗前,mMRC、CAT及SGRQ评分均低于治疗前,治疗组FEV_(1)%Pred、FEV_(1)/FVC均高于对照组,6MWT长于对照组,差异有统计学意义(P<0.05);两组mMRC、CAT及SGRQ评分比较差异无统计学意义。治疗组急性发作次数少于对照组,差异有统计学意义(P<0.05);两组药物不良反应发生率比较差异无统计学意义。结论布地格福气雾剂能更好地改善患者的肺功能和运动耐力,减少急性发作次数,且不增加药物不良反应。

噻虫嗪棉花种子包衣的残留动态及与棉蚜防效的相关性分析

【目的】新烟碱类杀虫剂具有的内吸活性和向顶传导特性,可用做种子处理来防治蚜虫、粉虱等刺吸式口器害虫,探讨噻虫嗪处理种子后农药的残留动态与防效的相关性,为其合理应用提供理论依据。【方法】以棉花为试材,用30%噻虫嗪悬浮种衣剂不同剂量进行种子包衣处理,调查防治效果的同时采集棉花植株样品,采用液质联用的方法分析棉花植株中噻虫嗪及其代谢产物噻虫胺在棉花植株中的残留及消解动态。【结果】噻虫嗪棉花种子包衣后,播后16 d首次采样,不同剂量噻虫嗪在棉花植株中的残留量为0.753~2.768 mg/kg,其代谢产物噻虫胺含量范围为0.278~0.894 mg/kg。随着时间的推移,两者残留量呈指数下降,播后66 d对棉花样品进行检测时,2种药物在棉花中的含量均小于检出限0.001 mg/kg,噻虫嗪及代谢产物噻虫胺在棉花中的消解动态均符合一级动力学方程。【结论】不同剂量噻虫嗪种子包衣可显著降低苗期蚜虫虫口密度,表现出明显的剂量效应,并且植株中的农药残留水平与棉蚜防治效果之间有较强的相关性,其作用机理可能与棉蚜刺探叶片后产生拒食效应有关。

噻虫嗪对蜜蜂健康影响研究进展

新烟碱类杀虫剂被广泛用于防治作物病虫害,然而过度使用导致的药物残留始终是一个不容忽视的问题,如噻虫嗪(Thiamethoxam)在我国主要蜜源植物油菜、棉花等的广泛应用,对授粉昆虫健康带来严重威胁。本文通过综述近几年噻虫嗪对蜜蜂采集飞行能力、生殖能力、生理免疫能力的相关研究,以及其与环境因子协同作用对蜜蜂健康所造成的潜在危害,强调了未来应加速研发高效防治靶标害虫以及对蜜蜂低毒或无毒的高选择性杀虫剂,以保障授粉昆虫安全。

3种常用杀虫剂对广西蒙山地区柑桔木虱的防治效果

2021年在广西蒙山县蒙山镇甘棠村金秋砂糖桔种植园柑桔木虱若虫发生初盛期,开展了常用杀虫剂螺虫乙酯、噻虫嗪和阿维菌素防治柑桔木虱的田间试验。结果表明,22.4%螺虫乙酯SC 4000倍液、21%噻虫嗪SC 3360倍液、1.8%阿维菌素EC 1440~2000倍液对柑桔木虱若虫防治效果在82%以上,均有较好的防治效果;其中,1.8%阿维菌素EC 1440倍液和21%噻虫嗪SC 3360倍液的防治效果相对更好,药后15 d时仍然分别可达96.07%和93.91%,两者防治效果差异不显著。3种药剂的持效期均可达15 d以上,可在柑桔木虱若虫发生初盛期交替使用。

设施芹菜噻虫嗪和高效氯氟氰菊酯连续施用后消散、积累与风险评估

噻虫嗪和高效氯氟氰菊酯是设施芹菜生产中常用的杀蚜虫剂,揭示其消解和积累特征对于评估其膳食摄入风险、优化施用方式具有重要意义。本研究采用气相色谱-串联三重四极杆质谱法,在质谱多反应监测模式下,通过田间残留试验,对2种杀虫剂在3种连续施药方式(组合I:噻虫嗪+高效氯氟氰菊酯,交替II:噻虫嗪-高效氯氟氰菊酯-噻虫嗪,交替III:高效氯氟氰菊酯-噻虫嗪-高效氯氟氰菊酯)下的残留消解动态进行了分析,并对长期膳食摄入风险进行了评估。结果表明:3种连续施药方式下,均在第2次施药(定植后22 d)后原始沉积量最高,首次施药后原始沉积量最低,而芹菜叶面积指数可能是导致该现象的重要因素。根据一级动力学方程拟合获得噻虫嗪和高效氯氟氰菊酯的消解半衰期分别为2.95~3.63 d和2.33~3.11 d。连续3次施药达到安全间隔期(PHI)(7 d)后,噻虫嗪和高效氯氟氰菊酯在组合I中的残留量仅在首次施药后低于MRL (噻虫嗪:1 mg/kg;高效氯氟氰菊酯:0.5 mg/kg);而交替II中2种农药残留量在3次施药后均低于MRL;交替III中高效氯氟氰菊酯残留量在第3次施药后超过了MRL。鉴于噻虫嗪施药后可代谢为噻虫胺,本研究亦对噻虫胺残留量进行了监测,发现其在施药后3~5 d达到最大值,但在达到安全间隔期后,噻虫胺的残留量均未超过其MRL (0.04mg/kg),表明由噻虫嗪代谢导致噻虫胺残留超标的风险较低。膳食摄入风险评估结果显示:在本次于浙江绍兴进行的田间规范残留试验中,噻虫嗪和高效氯氟氰菊酯组合和交替连续施药3次,安全间隔期7 d后,所采集的芹菜样品中噻虫嗪和高效氯氟氰菊酯残留对风险商的贡献率(0.11%~3.76%)低于100%,其长期膳食摄入风险均处于可接受水平。研究表明,相较于组合施药,交替用药可在一定程度减少农药残留,而噻虫嗪-高效氯氟氰菊酯-噻虫嗪交替施用表现出最低的残留水平和膳食摄入风险贡献率,是相对最佳的施药策略。

泉州地区红火蚁发生情况调查及防治药剂筛选

为明确泉州地区红火蚁的发生情况,筛选适合当地的红火蚁高效防控药剂。通过调查了当地红火蚁的栖息环境、生活习性和传播途径,测定1%噻虫胺颗粒剂、1.8%阿维菌素乳油、0.05%茚虫威杀蚁饵剂和5%鱼藤酮可溶液剂对红火蚁的田间防治效果,筛选最佳防控药剂。结果表明:泉州地区的红火蚁主要分布在草地(草坪)、苗圃、公园、农田、果园和绿化带等地带,其适宜的活动温度为19~32℃,食性杂、适应性强、传播扩散方式多样。田间药效试验显示,1%噻虫胺颗粒剂和0.05%茚虫威杀蚁饵剂对活动蚁巢和活动工蚁均具有好的速效性和持效性;5%鱼藤酮可溶液剂虽然速效性略慢,但持效性也较好;1.8%阿维菌素乳油的速效性和持效性均较差;因此,1%噻虫胺颗粒剂、0.05%茚虫威杀蚁饵剂和5%鱼藤酮可溶液剂适宜在田间推广应用。本研究结果可为制定针对性的防控措施提供技术支持和科学依据。

噻虫嗪及其代谢物噻虫胺在枸杞中的残留消解及膳食摄入风险评估

为分析50%噻虫嗪水分散粒剂在枸杞上的残留情况,评估其残留量对人体的膳食摄入风险,建立了噻虫嗪及其代谢物噻虫胺在枸杞上的高效液相色谱-串联质谱检测方法,分析枸杞中农药的最终残留量,估算农药慢性摄入风险。结果表明,在0.01~1.0 mg/L的范围内,2种农药的线性关系良好,相关系数大于0.999。在0.01、0.1、1.0 mg/kg 3个添加水平下,平均回收率为80.7%~106.6%,相对标准偏差为1.4%~4.6%。储藏稳定性试验结果表明,冷冻条件下储藏11个月,噻虫嗪和噻虫胺在枸杞中均稳定。中国居民摄入噻虫嗪和噻虫胺的慢性暴露风险分别为16.6%和3.8%,远低于100%,慢性膳食暴露风险低。

2种不同种衣剂对玉米黑糯100生长状况和抗氧化防御系统的影响

本研究通过田间试验,选择噻虫嗪和噻虫嗪-苯醚甲环唑混剂2种内吸性农药作为玉米种衣剂,探究了种衣剂对玉米乳熟期果穗鲜重,不同生长时期各部位鲜重的影响,以及对玉米植株抗氧化防御系统的影响。结果表明:以推荐使用剂量(6 mL/kg种子),种衣剂对玉米植株各部位鲜重的影响主要在玉米苗期和拔节期,相比对照处理,噻虫嗪和噻虫嗪-苯醚甲环唑混剂处理明显降低玉米苗期和拔节期各部位鲜重,乳熟期时3个处理之间差异不显著;施用种衣剂能增加果穗鲜重,但增加效果不明显。种衣剂处理均促进植株叶绿素的合成,且噻虫嗪和苯醚甲环唑混施较单施噻虫嗪玉米叶绿素含量更高。单施噻虫嗪和噻虫嗪与苯醚甲环唑混合施用均会引起玉米叶片中抗氧化酶SOD、CAT和POD活性的提高,使叶片GSH和MDA含量降低,说明在本试验施用的种衣剂剂量胁迫环境下,玉米叶片抗氧化防御系统可作出应答,调节细胞的代谢过程,使玉米植株正常生长。

超高效液相色谱串联质谱法测定水果中噻虫胺、噻虫嗪和吡虫啉的含量

目的:建立超高效液相色谱串联质谱法同时测定水果中噻虫胺、噻虫嗪和吡虫啉含量的方法。方法:用0.1%甲酸乙腈溶液超声提取试样中的噻虫胺、噻虫嗪和吡虫啉残留物,采用QuEChERS净化,超高效液相色谱-质谱/质谱仪测定,外标法定量。结果:该方法在2~200 ng·mL^(-1)浓度范围内线性关系好,回收率在89.2%~97.5%,精密度在1.0%~6.1%。结论:方法具有灵敏度高、稳定性好、准确度高的优点,可以同时有效地测定水果中噻虫胺、噻虫嗪和吡虫啉的含量。

2种药剂和食诱剂对桃园防治橘小实蝇效果评价

橘小实蝇是严重为害果蔬生产的经济性害虫.筛选评估低毒低残留的药剂及食诱剂是控制橘小实蝇危害的重要策略.本研究选择了当前果树生产中常用的多杀菌素、噻虫嗪2种低毒高效药剂以及聪绿食诱饵剂,通过田间连续调查评估对桃园中橘小实蝇的防治效果.结果表明,喷施多杀菌素和噻虫嗪对橘小实蝇防治有明显效果,药效可持续1 w左右.聪绿饵剂前期防控效果比较稳定,且结合套袋方式可以有效提高诱杀效果.

噻虫嗪种衣剂对玉米苗期两种粘虫的室内毒力测定

本研究采用胃毒法测定了噻虫嗪悬浮种衣剂(SC)对东方粘虫[Mythimna separata(Walker)]和劳氏粘虫[Mythimna loreyi(Duponchel)]的室内毒力。结果表明,35%噻虫嗪SC有效成分质量浓度在1.12~2.24 g/kg之间对两种粘虫均具有明显的毒力,且在玉米不同苗龄对不同龄期及种类粘虫的毒力均存在一定差异。玉米出苗2周,噻虫嗪SC质量浓度为1.12 g/kg时对东方粘虫2龄幼虫的毒力效果达92.83%,对劳氏粘虫2龄幼虫的毒力效果达57.13%。与劳氏粘虫相比,噻虫嗪SC对东方粘虫的毒力更强。本研究为生产上选用噻虫嗪SC防治玉米粘虫提供了参考。

液相色谱-串联质谱法分析噻虫嗪在菜薹上的残留行为

为了明确噻虫嗪在菜薹上使用后的残留行为,在6个省市开展了噻虫嗪在菜薹上的最终残留试验,在其中2个省份开展了消解动态试验。样品采用固相萃取柱净化,高效液相色谱-串联质谱法(HPLC-MS/MS)测定,外标法定量。结果表明:添加水平在0.01~1.0 mg/kg下,噻虫嗪及其代谢物噻虫胺在菜薹中的添加回收率为89%~102%和93%~100%,相对标准偏差为5.8%~8.5%和4.0%~9.5%,定量限(LOQ)为0.01 mg/kg。消解动态试验结果表明,山东和安徽两地噻虫嗪在菜薹上的降解半衰期分别为1.8 d和1.2 d;6个省市的最终残留试验结果显示,用药量56.25~84.375g a.i./hm^(2),施药2~3次,药后10 d,收获的菜薹中噻虫嗪的残留量为<LOQ~0.125mg/kg。推荐25%噻虫嗪水分散粒剂防治菜薹上菜薹跳甲时,最高用药量56.25g a.i./hm^(2),最多施药2次,推荐安全间隔期为7 d。