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.

Chronic toxicity and cytotoxicity of synthetic pyrethroid insecticide cis-bifenthrin

With the increasing use of synthetic pyrethroids （SPs）, the significance of ecological safety and health risk is an emerging concern, In this study, we evaluated the chronic aquatic toxicity of eis-bifenthrin （cis-BF） in Daphnia magna and its cytotoxicity in Chinese hamster ovary （CHO） cells as well as human cervical carcinoma （Hela） ceils. Chronic aquatic toxicity tests showed that cis-BF could significantly affect the reproduction of D. magna. The lowest observed effective concentration and the non-observed effective concentration of cis-BF to D. magna were 0.02 and 0.01 μg/L, respectively, and the chronic value was 0.014 μg/L. The intrinsic rate of natural increase was significantly decreased （p 〈 0.05） to 0.02 μg/L. The cytotoxicity assay demonstrated that cis-BF decreased cell viability in CHO and Hela cells in a concentration- and time-dependent manner. The IC50 values for Hela and CHO cells were 4.0 × 10^-5 and 3.2 × 10^-5 mol/L, respectively. Together, these results indicated that cis-BF induced chronic toxicity in both aquatic invertebrate animals and mammalian cells. These findings assist in understanding the impact of SPs on health and environmental safety. Considering the wide spectrum of SPs, a more comprehensive understanding of the negative effects is indispensible for planning future application and regulation of these pesticides.

Effects of bifenthrin on Daphnia magna during chronic toxicity test and the recovery test

The acute and chronic toxic effects of bifenthrin on Daphnia magna were studied. The results showed that 24 h-EC 50 , 48 h-LC 50 and 96 h-LC 50 of bifenthrin on D. magna were 3.24, 12.40 and 1.40 μg/L respectively. And the LOEC and NOEC of bifenthrin were 0.02 and 0.004 μg/L respectively. The recovery test of bifenthrin on Daphnia magna was presented. Daphnia magna(F 0 generation) were exposed during 21 d to different bifenthrin concentrations. Offspring(animals from the first and third brood: F 1(1st) and F 1(3rd), respectively) were transferred to a free pesticide medium during a 21 d recovery period. In this recovery study, survival, growth, reproduction(mean total young per female, onset of reproduction and number broods per female) and the intrinsic rate of natural increase (r) were assessed as parameters. Reproduction such as number of young per female as well as length was still reduced in F 1(1st) generation daphnids from parentals(F 0) exposed to the bifenthrin. However F 1(3rd) individuals from parentals exposed to pesticide concentrations were able to restore reproduction when a recovery period of 21 d was allowed, but the length of F 1(3rd) from parentals exposed to the 0.5 and 0.75 μg/L bifenthrin concentration was still significantly effected(P<0.05).

Exposure to bifenthrin disrupts the development of testis in male Sebastiscus marmoratus

Bifenthrin（BF） is a pyrethroid insecticide that is widely used in agriculture, horticulture, and for residential purposes. However, few studies addressing the reproductive toxicity of BF on fishes are available. The present study was conducted to investigate the effects of BF on testicular development in Sebastiscus marmoratus and to gain insight into its mechanism. After exposure to 1, 10 and 100 ng/L BF for 50 days, there was a reduced number of mature sperm and an abundance of the late stages of spermatocysts in the testes. The levels of 17β-estradiol and testosterone were decreased significantly after BF exposure. The activity of caspase-3 was increased in a dosedependent manner after BF exposure, TUNEL assay indicated that BF exposure resulted in the occurrence of apoptosis in the testes, which might be main reason for the inhibition of spermatogenesis.

Analysis of Bifenthrin Degrading Bacteria from Rhizosphere of Plants Growing at Tannery Solid Waste

Bifenthrin is an insecticide which is used to control insects, mites, and ticks. It poses a solemn en-vironmental threat and health risk to living organisms. It may be bioaccumulated or biomagnified at different trophic levels in the food chain by biota. Microbes are hidden creature of earth’s biodiversity. For isolation of bifenthrin degrading bacteria, rhizospheric soil samples of plants like Pisum sativum, Triticun aestvum, Chenopodium album were taken from tannery solid waste, Kasur, Pakistan. Enrichment culture techniques were used for the isolation of bacterial strains that showed luxurious growth on minimal growth media with bifenthrin dose was selected for biodegradation study. Bacteria were further screened out based on their morphological, biochemical parameters and degradation efficiency. Furthermore the effect of different growth factors like temperature, pH, inoculum concencentration, minimal inhibitory concentration of heavy metals and antibiotics were also studied. Bacterial strains of Xanthomonas and Bacillus sp. were identified as efficient degrading microbes. Maximum bifenthrin utilization were observed at 25°C (pH 7), with 500 μL inoculum of Bacillus sp., while Xanthomonas sp. gave optimm utilization at 30°C (pH 7) at the same inoculum volume of bacteria. The Rf values of Bacillus sp. and Xanthomonas sp. were 0.91 and 0.90 respectively, which indicated their potential to metabolize bifenthrin into nontoxic forms. These strains can be used to clean up the sites polluted with pesticides and tannery wastes when present in rhizosphere of plants.

Characterizing Rhizodegradation of the Insecticide Bifenthrin in Two Soil Types

Rhizodegradation is a process by which plant-supplied substrates stimulate microbial populations in plant root zones (rhizospheres) to cause removal of undesirable levels of contaminants in soil. This study characterized rhizodegradation of the insecticide bifenthrin in Armour silt loam and Sullivan fine sandy loam soils that were planted with switchgrass, big bluestem, and alfalfa. After six weeks in soils, plate dilution frequency assays (PDFA) of bacterial populations were higher in all planted soils than in unplanted ones. Planted Sullivan soils contained higher bacteria than corresponding Armour soils and alfalfa rhizospheres of both soil types contained highest bacteria. Bacterial populations generally increased between week 6 and week 10, before declining in each treatment at week 12. Carbon utilization patterns (CUP) of bacterial communities, measured as color development on BIOLOG plates, were higher in planted soils than in unplanted ones. Principal Component Analysis (PCA) constructed patterns based on different extents of color development;these patterns were used to relate microbial communities in the different treatments. Gas chromatography (GC-ECD) showed that significantly more bifenthrin dissipated in planted soils than unplanted ones. Different levels of bifenthrin were recovered in planted soils but the differences were generally not significant. Data are being evaluated further to provide a basis for the development of strategies for enhancing rhizodegradation of soils contaminated with bifenthrin.

Protective effects of EGCG on Bifenthrin-Induced Oxidative Stress in the Human Embryonic Lung Fibroblast Cell Line HFL-I

Bifenthrin(BF) is an important type I synthetic fluorinated pyrethroid insecticide and acaricide.Previous investigations have indicated that the metabolisms of BF in human cells were through oxidative processes,and cytotoxicity was induced by the oxidative stress.In this study,the protective effects of EGCG,which is a major individual of green tea polyphenols,on the human embryonic lung fibroblast cell line HFL-I exposed to BF were investigated.The results showed that BF could induce oxidative stress leading to cytotoxicity in HFL-I cells.The pretreatment of EGCG at low concentrations significantly recovered the cell viability and morphology,inhibited excess generation of ROS,enhanced antioxidant enzyme activities and avoided loss of mitochondrial membrane potential.The results suggested that EGCG might eliminate the BF-induced damage in HFL-I cells.

绿茶中联苯菊酯和氯氟氰菊酯残留检测质量控制基体标准物质的研制

目的:制备一批绿茶中联苯菊酯和氯氟氰菊酯基体标准物质。方法:以绿茶为研究对象,通过喷洒联苯菊酯和氯氟氰菊酯,样品经粉碎、过筛、均质、装瓶,通过均匀性、稳定性检验后,由3家实验室联合定值确定量值,并进行不确定度评估。结果:绿茶中联苯菊酯和氯氟氰菊酯的量值分别为(0.185±0.0197),(0.207±0.0466)mg/kg,k=2,置信区间为95%。结论:研制出的绿茶中联苯菊酯和氯氟氰菊酯基体标准物质足够均匀,足够稳定,定值结果可靠。

湿润土壤中联苯菊酯残留的高效液相色谱检测

为提高房屋白蚁化学屏障质量检测工作效率,在长沙市5个工地基坑中喷洒不同药量的联苯菊酯悬浮剂,比较自然风干土样和湿润土样的药物残留值。结果表明:湿润土样和自然风干土样的联苯菊酯出峰时间基本一致;2种不同样品提取和计算得到的残留检测结果接近,平均误差值均小于3%,并且差异性不显著。综之可知,湿润土样不经过自然风干,直接进行样品提取和计算的方法适用于土壤中联苯菊酯悬浮剂残留量的检测。

3种有益菌对联苯菊酯残留晒青毛茶固态发酵过程中多酚类物质含量影响的研究

为了探明有益菌对联苯菊酯农药残留晒青毛茶固态发酵中茶多酚类物质含量的影响,以期为普洱茶固态发酵工艺的优化及普洱茶农药残留安全性标准的制定提供科学依据。采用高效液相色谱技术分析鉴定了不喷联苯菊酯不接菌、不喷联苯菊酯接酿酒酵母菌、黑曲霉、产黄青霉,喷施联苯菊酯后不接菌、喷施联苯菊酯后接酿酒酵母菌、黑曲霉、产黄青霉8种固态发酵处理下普洱茶茶多酚类物质含量。结果表明联苯菊酯农药的喷施使茶多酚类物质的含量极显著低于喷药前(P <0.01);喷联苯菊酯后接菌的发酵样中各时期茶多酚类物质含量极显著低于不喷联苯菊酯接菌的发酵样(P <0.01),极显著高于喷施联苯菊酯不接菌的发酵样(P <0.01)。联苯菊酯农药残留给普洱茶的滋味和安全带来不良影响,有益菌的利用可以降低茶多酚类物质含量的减少,为普洱茶的品质改善和安全性提供保障。

亚急性浓度暴露下联苯菊酯对真鲷体内酶活性及肝细胞DNA损伤的影响

联苯菊酯是一种广泛应用的拟除虫菊酯类农药,但有关联苯菊酯对海水鱼类的毒性机理研究较少。为研究亚急性暴露下联苯菊酯对真鲷的毒性效应,在急性毒性试验基础上,选取5个浓度梯度对真鲷进行半静置暴露试验,测定不同暴露时间体内酶活性变化,并开展暴露25 d后肝细胞彗星试验。结果表明,亚急性暴露下真鲷血清中乙酰胆碱酯酶(AChE)、血细胞中Na^(+)-K^(+)-ATP酶(Na^(+)-K^(+)-ATPase)、肝和鳃中谷胱甘肽硫转移酶(GST)等酶活性先后出现了诱导或抑制现象。暴露浓度低于0.10μg·L^(-1),联苯菊酯对真鲷血清中AChE、血细胞中Na^(+)-K^(+)-ATPase和肝中GST等酶活性主要表现为诱导作用(P<0.05)。暴露浓度高于0.10μg·L^(-1),AChE活性受到显著抑制(P<0.05);暴露浓度高于0.20μg·L^(-1),Na^(+)-K^(+)-ATPase、GST活性均受到显著抑制(P<0.05)。与对照组相比,各暴露浓度组肝细胞DNA均有不同程度损伤,彗星拖尾率、彗星尾长、彗尾DNA相对含量、Olive尾距与对照组之间均差异显著(P<0.02)。回归分析显示,暴露浓度与各试验指标数据呈线性关系,R^(2)值范围在0.906~0.984之间。暴露浓度高于0.10μg·L^(-1)时,联苯菊酯可显著影响真鲷体内酶活性,并对肝细胞DNA产生不同程度损伤,具有一定遗传毒性和潜在生态风险。

离子液体-分散液液微萃取结合高效液相色谱法快速分析茯苓中氰戊菊酯和联苯菊酯农药残留

离子液体-分散液液萃取法被成功地应用于萃取和富集中药材茯苓中氰戊菊酯和联苯菊酯。1-辛基-3-甲基咪唑六氟磷酸盐([C_8mim][PF_6])作为萃取溶剂,1-丁基-3-甲基咪唑四氟硼酸盐([C_4mim][BF_4])为分散剂。整个萃取过程不需要加入任何有机溶剂,萃取过程快速,3min内就可以达到萃取平衡。茯苓中目标化合物的加样回收率在95.7%~98.3%之间,检出限为0.50和0.40 ng·mL^(-1)之间,结果令人满意,说明该实验方法适用于检测中药材中氰戊菊酯和联苯菊酯农药残留。

茶叶和土壤中cis-联苯菊酯、高效氯氟氰菊酯手性对映体残留分析

为了满足茶叶和土壤中手性农药cis-联苯菊酯和高效氯氟氰菊酯对映异构体残留检测的需要,本试验首次对比研究了正相液相色谱条件下,Daicel ChiralPak®AS-H、Phenomenex®Cellulose-1和Cellulose-3柱对两组手性对映体的拆分效果,以及气相色谱条件下BGB-172柱的分离测定效果,并建立了基于手性气相色谱分离的茶叶和土壤中cis-联苯菊酯和高效氯氟氰菊酯对映体残留分析方法。样品采用正己烷和丙酮提取,Florisil与GCB混合柱净化,气相色谱手性柱BGB-172程序升温分离,电子捕获检测器(ECD)外标法定性定量测定。结果表明,在2.5~800μg·L^(-1)浓度范围内,cis-联苯菊酯对映体色谱峰面积(Y)与浓度(x)之间分别满足线性方程Y=15381.1x-279657.5(r=0.9967)和Y=17387.6x-399048.0(r=0.9937),对映体分数(EF值)=0.489±0.017;在2.5~200μg·L^(-1)浓度范围内,高效氯氟氰菊酯对映体分别满足线性方程Y=22083.8x-161004.3(r=0.9923)和Y=23001.1x-167694.8(r=0.9922),EF=0.492±0.008。在0.005、0.050和0.50 mg·kg^(-1)3个添加浓度水平下,cis-联苯菊酯和高效氯氟氰菊酯对映体在不同茶叶、土壤样品中的平均添加回收率为61.6%~123.4%,相对标准偏差(RSD)为2.5%~14.6%,检测限低于0.001 mg·L^(-1),方法定量限低于0.005 mg·kg^(-1),不同样品中未见到明显基质效应。综上,该方法能够满足cis-联苯菊酯和高效氯氟氰菊酯对映体残留分析的需要,用于研究茶鲜叶中cis-联苯菊酯和高效氯氟氰菊酯对映体残留消解,且无明显对映体选择性差异。本研究结果为进一步开展2种手性农药在茶叶生长和加工过程中的残留和消解规律研究提供了技术支持。

1%联苯·噻虫嗪颗粒剂对甘薯小象甲的田间防效试验

为探索新型1%联苯·噻虫嗪颗粒剂(颖壮)对甘薯小象甲的防效及对甘薯产量和品质的影响,于2021年在广东省湛江、汕尾和惠州开展了3个田间防效试验。结果表明:1%联苯·噻虫嗪颗粒剂5和6 kg/667m^(2)平均防效分别为78.56%和79.05%,与当地常规施药(多药剂联合多次施药)的平均防效79.22%相当,增产率分别为6.21%和7.17%,显著高于当地常规施药的增产率3.94%,商品薯率也较当地常规施药及空白对照有明显的增加。因此,1%联苯·噻虫嗪颗粒剂(颖壮)可以作为防治甘薯小象甲的高效低风险农药,在鲜食型甘薯生产上具有较大的应用潜力。

溴虫氟苯双酰胺与联苯菊酯复配对黏虫的联合毒力测定

为筛选出防治黏虫的高效杀虫剂,通过喷雾法测定了溴虫氟苯双酰胺和联苯菊酯复配对黏虫的联合毒力。结果表明:溴虫氟苯双酰胺和联苯菊酯以质量比5∶1、3∶1、1∶1、1∶3和1∶5复配对黏虫的共毒系数分别为122.37、141.50、102.19、114.68和117.11。综合考虑,3∶1为溴虫氟苯双酰胺和联苯菊酯混配的最佳配比。

马尾松木材联苯菊酯防腐浸泡工艺研究

为探索低成本、高效率的马尾松木材联苯菊酯防腐浸泡工艺,采用正交试验法,研究浸泡工艺对马尾松锯材增重率和联苯菊酯载药量的影响。结果表明:联苯菊酯浓度对增重率和载药量的影响最大,其次为浸泡时长,最后为浸泡深度,其中联苯菊酯浓度和浸泡时间对增重率和载药量有显著性影响。综合企业实际生产,本研究以时间为优化条件,确定的较优工艺为:联苯菊酯浓度0.05%、浸泡时长6 h、浸泡深度为50 mm。以此工艺浸泡的马尾松锯材,联苯菊酯载药量为0.059%,满足AS/NZS 1604.1:2021 Preservative-treated wood-based products Part 1:Products and treatment对联苯菊酯的限值要求。

食用农产品中农药残留状况调查报告

通过对市面上374批次的食用农产品进行26种农药残留检测,经过数据分析统计市面上的食用农产品中存在农药残留的情况。结果表明:农药残留检出率为26%,苯醚甲环唑、氯氟氰菊酯、氯氰菊酯、毒死蜱、联苯菊酯是被检出最多的5种农药。虽然食用农产品存在农药残留的情况,但是目前食用农产品还是安全可靠的。

毛细管气相色谱法同时测定苹果 梨中氯氰菊酯联苯菊酯和氟氯氰菊酯的残留量

利用乙腈提取、氧化铝和弗罗里硅土填料净化的前处理方法,研究了采用毛细管气相色谱同时测定苹果、梨中氯氰菊酯、联苯菊酯和氟氯氰菊酯残留量的方法。结果表明,用20mL10%丙酮/石油醚作为淋洗液,0.5mg·L-1水平时苹果、梨在两种填料的回收率都在90%—120%之间;在0.05mg·L-1水平时,苹果、梨在弗罗里硅土柱上,3种菊酯都达到了90%—110%的满意结果;而在氧化铝柱上,只有联苯菊酯和氟氯氰菊酯达到90%—110%的结果,氯氰菊酯只达到64.8%和61.5%的结果。综合考虑,利用弗罗里硅土柱对这3种菊酯的净化效果较好,高低浓度均符合农药残留分析的要求。

4种农药对意大利蜜蜂的毒力测定

利用摄入法测定联苯菊酯、溴氰菊酯、双甲脒和氟胺氰菊酯对意大利蜜蜂工蜂的毒性。结果表明,4种农药对意大利蜜蜂工蜂的LC50分别为16.263、62.900、302.784、1001.755mg/L。

两株拟除虫菊酯类农药高效降解菌混合降解性能研究

从拟除虫菊酯类农药生产车间下水道驯化污泥中分离筛选出两株可同时降解联苯菊酯、甲氰菊酯、氯氰菊酯的高效菌株M6R9和M5R14,经鉴定为产气肠杆菌Enterobacter aerogenes和缺陷假单胞菌Pseudomonas diminuta。通过单一菌和混合菌对比实验,发现单一菌及混合菌对联苯菊酯、甲氰菊酯、氯氰菊酯的降解率均与接菌量(OD415nm)呈正相关,且降解过程满足一级动力学方程。在含联苯菊酯、甲氰菊酯、氯氰菊酯各100mg/L的基础培养基中,接菌量相同(单一菌OD415nm均为0.2,混合菌中M6R9和M5R14的OD415nm各为0.1),于30℃、pH7.0、180r/min下培养3d,发现混合菌对联苯菊酯、甲氰菊酯、氯氰菊酯的降解率分别比单一菌M6R9和M5R14提高2.5%、3.4%、2.3%和14.5%、14.6%、15.5%,半衰期分别缩短8.1、14.8、13.1h和40.3、50.7、46.4h,表明混合菌对联苯菊酯、甲氰菊酯、氯氰菊酯的降解存在协同作用,即混合菌可提高3种菊酯类农药残留的去除率。