Long Term Administration of Lannea acida Rich. (Anacardiaceae) Reverses the Imidacloprid-Induced Fertility Impairments in Adult Male Rat through Androgenic and Antioxidant Properties

Aim: The harmful effects of pesticides have been largely documented in recent times. But effective therapeutic solutions to pesticide related male infertility are yet to be established. This study investigated the curative effects of Lannea acida on imidacloprid (IMI)-induced hypofertility in male Wistar rats. Methods: Rats of 150 – 200 g were administered IMI (22.5 mg/kg) for two weeks and partitioned into control (distilled water, vitamin E, clomiphene citrate) or test (aqueous (340 mg/kg), methanol (170 mg/kg) extract) groups for eight weeks treatment. Animals were sacrificed at the end of the treatment and samples were collected for sperm, antioxidant and hormonal analysis. Fertility tests were performed from treatment day 47 for fertility indices estimation. Results were expressed as mean ± SEM and one way ANOVA was applied using STATISTICA Software. Results: Exposition to IMI resulted in a significant decrease in sperm count, motility, viability and normality, testosterone and LH, coupled to an increase in oxidative stress markers. Moreover, IMI impaired male fertility evidenced by a significant drop in fertility index and litter size. Similar to clomiphene citrate and vitamin E, plant extracts significantly improved the sperm parameters, sexual hormones and decreased the oxidative stress markers. More importantly, the fertility index and litter size were restored, especially with the aqueous extract. Conclusion: Present results indicate that L. acida possesses curative potentials against IMI-induced hypofertility through its androgenic and antioxidant properties. However, the effects the extract on spermatozoa DNA structure and the fertility of offsprings from exposed parents are yet to be studied to conclude on total recovery from IMI toxicity.

Synthesis and Identification of Artificial Antigen for Imidacloprid

This study reported that a hapten of imidacloprid, 1-[（6-Carboxylethylthio-3- pyridinyl）methyl]-N -nitro-imidazolidinimine was synthesized using technical material of imidacloprid to react with 3-mercaptopropionic acid in hot alkaline solution. The hapten was conjugated to bovine serum albumin （BSA） and ovalbumin （OVA） to form the immuno-antigens and the coating antigen, respectively. The antibody with high titer （2.56 × 10^4） was obtained after immuning rabbits. The results showed that the antibody had a high affinity to imidacloprid tested by enzyme-linked immunosorbent assay （ELISA）, which IC50 and IC20 were 20.7 and 1.1 μg L^-1; and the cross reactibilities to those compounds related with imidacloprid were less than 1.4%.

Application of imidacloprid controlled-release granules to enhance the utilization rate and control wheat aphid on winter wheat

During winter wheat production, aphids need to be controlled with pesticides for the entire growth period. Controlled-release technology has been regarded as an alternative method for the improvement of pesticide efficiency. This study investigated two types of imidacloprid controlled-release granule (CR-GR): 2% imidacloprid CR-GR and 0.2% imidacloprid pesticide-fertilizer controlled-release granule (PF-CR-GR) when wheat was sown in winter. The release performance, utilization rate, terminal residues in edible parts, control effect on aphids, and achieved winter wheat yield were evaluated for both laboratory experiments and field application. Imidacloprid PF-CR-GR released more quickly in aqueous medium than CR-GR because of its good water solubility. After CR-GR treatments, the concentrations in wheat roots and soil were similar throughout the entire sampling period, and the concentrations in shoots were about 10–20% of those in roots. Imidacloprid was better absorbed when CR-GR was used as root treatment, compared with foliar treatment. Field application showed that imidacloprid CR-GR and PF-CR-GR controlled aphids throughout the entire growth period of winter wheat and improved the wheat yield. These findings identified application of imidacloprid CR-GR and PF-CR-GR on winter wheat as an effective way to enhance the pesticide utilization rate and ensure adequate yield. This paper provides a theoretical basis for the scientific use of pesticides and guides scientific pesticide application.

Adsorption and Leaching Potential of Imidacloprid Pesticide through Alluvial Soil

This study was aimed to assess the adsorption and leaching potential of imidacloprid pesticide in column and field soil. To visibly understand these actions and factors affecting them, the experiments were carried out under laboratory and field conditions. Adsorption study was divided into kinetic and equilibrium sections. The evaluation of kinetic data was done through pseudo first and second order models. It was found that kinetic adsorption of imidacloprid on soil followed pseudo second order with rate constant value of 4.333 mg/g/h. Langmuir and Freundlich isotherms were used to explain equilibrium adsorption, from these isotherms it was evaluated that Freundlich isotherm was obeyed well with adsorption capacity of 2.190 - 4.573 mol/g. Leaching study was performed in laboratory using column made of poly-vinyl chloride having 30 cm length. Known amount of imidacloprid pesticide was applied to column left for adsorption and then eluted with 500 mL water in five equal portions. These water portions and soil of column which was divided into three sections were analyzed by HPLC. The result revealed that the concentration of imidacloprid was decreased from 0.481 ppm in first portion of water to 0.327 ppm in last portion of water while 0.783 ppm in first section of column soil to 0.038 ppm in last section of column soil. In field the leaching power of imidacloprid was observed up to 60 cm depth, its concentration decreased with soil depth. It was 3.311 ppm in first portion of soil and 0.357 ppm in last portion of soil. The leaching potential of imidacloprid pesticide up to 60 cm soil depth was due to less organic matter, sandy texture, alkaline pH, and low cation exchange capacity.

Photochemistry of insecticide imidacloprid: direct and sensitized photolysis in aqueous medium

The direct and sensitized photodegradations of imidacloprid, 1-(6-chloro-3-pyridinylmethyl)-N-nitro-2-imidazolidinimine, were investigated in aqueous solution and with and without various photo-sensitizers. Results of the study revealed that the intensity of lamp-house and irradiation wavelength had significant effects on the photolysis of imidacloprid. Complete degradation of 20 mg/L imidacloprid in aqueous phase was observed in 40 min under ultraviolet(UV) irradiation system, suggesting the ultraviolet ray played significant role in direct photolysis of imidacloprid. The additions of various photo-sensitizers lead to improve the degradation efficiency of imidacloprid under the irradiation of black light fluorescent lamp. TiO 2 was the most efficient in the photo-catalytic degradation of imidacloprid among other photo-sensitizers in used this study. However, addition of acetone inhibited the photolysis of imidacloprid under the irradiation of UV, indicating the occurrence of competition between acetone and imidacloprid for photos. Mineralization of the imidacloprid was examined to clarify the final photochemical degradation products of the insecticide which were CO 2, Cl- and NO- 3. Complete photo-oxidation of nitrogen to NO- 3 occurred very slowly via the intermediate formation of NH+ 4 and NO- 2.

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.

Epidemiology of Okra Yellow Vein Mosaic Virus (OYVMV) and Its Management through Tracer, Mycotal and Imidacloprid

Field trials were conducted to evaluate the epidemiological factors of okra yellow vein mosaic virus (OYVMV). Four varieties of okra were subjected to screening and evaluation of the chemicals. The variety Saloni F1 was highly resistant while Subz Pari was moderately resistant. Diksha was the tolerant variety while Lush Green was moderately susceptible. The chemical Imidacloprid was most effective to control whitefly population and okra yellow vein mosaic virus (OYVMV). Correlation of environmental factors (maximum and minimum temperature, relative humidity and rainfall) with percent plant infection of okra yellow vein mosaic virus (OYVMV) was also determined. There was a significant correlation between environment and disease severity.

Mechanisms of imidacloprid resistance in Nilaparvata lugens by molecular modeling

Homology models of the ligand binding domain of the wild-type and Y151S mutant brown planthopper {Nilaparvata lugens)α1 and rat(Rattus norvegicus)β2 nicotinic acetylcholine receptor(nAChR) subunits were generated based on the crystal structure of acetylcholine binding protein of Lymnaea stagnalis.Neonicotinoid insecticide imidacloprid was docked into the putative binding site of wild-type and mutantα1β2 dimeric receptors by Surflex-docking,and the calculated docking energies were in agreement with experimen...

Lethality of Imidacloprid and Fipronil on Apis mellifera: A Retrospective Analysis on the French Case

The aim of this study was to draw a retrospective analysis on the lethality of Imidacloprid(Gaucho®)and Fipronil(Régent TS®)on Apis mellifera between 1992 and 2016 in France.Early monitoring reports in the 1992-2002 period notified these two embedded insecticides to be at the origin of massive colony collapse disorders.Ecotoxicological analyses based on the LD50 of Imidacloprid and Fipronil highlighted their differential lethality by both contact(Imidacloprid:81 ng/honeybee vs.Fipronil:5.9 ng/honeybee)and ingestion(Imidacloprid:3.7 ng/honeybee vs.Fipronil:4.2 ng/honeybee),but failed to point Imidacloprid’s high solubility as a higher lethal agent.Chemical properties and action mode of these two insecticides originated neural disfunction in the case of Imidacloprid,and honeybee brood immune depression for Fipronil.Despite the conduction of these monitoring reports and laboratory researches,Fipronil was completely banned in 2005 but Imidacloprid only in 2016.

Storage Stability of Imidacloprid Residues in Different Matrixes of Lycium barbarum

The storage stability and degradation trends of imidacloprid residues in different matrix of Lycium barbarum were investigated by directly adding 0.1 mg/kg imidacloprid, frozen storage and phase detection. The results showed that under frozen condition, the storage stability of imidacloprid residues remained good for half a year in dry fruit, and a year in fresh fruit of L. barbarum . There was no significant change of imidacloprid residues between different processing of dry fruit and fresh fruit, and sample processing methods （crushing or homogenizing） had no significant effect on the degradation trends of imidacloprid. Therefore, the samples could be processed into crushed samples or homogenized samples for storage as soon as possible according to the needs, and the dry fruit should be detected within half a year, while the fresh fruit should be detected within a year.

Field Efficacy of Imidacloprid against Dendrobium officinale Aphid

[Objective]The paper was to investigate the control effect of imidacloprid against Dendrobium officinale aphid. [Method]The control effects of 70%imidacloprid WP 4 000,5 000 and 6 000 times dilution and 10% imidacloprid 750 times dilution on D. officinale aphid were studied,respectively. [Result]70%Imidacloprid WP had quick and durable control effects on D. officinale aphid,and the control effect improved with the increasing concentration. The control efficacy at 7 d post secondary administration was up to 95. 4%-97. 8%. [Conclusion]70% Imidacloprid WP is safe to crops within the test dosage,and can be used for prevention and control of D. officinale aphid.

Contact toxicities of imidacloprid on rice brown plant hopper(Nilaparvata lugens Stal)

Rice brown planthopper (BPH) (Nilaparvata lugens Stal, ) which occurs 4 generations within one year in Jiangsu Province has become a serious pest and causes loss of yield on rice every year in this region. The contact toxicities of imidacloprid and methamidophos to rice BPH were tested by means of immerse topical application method and a field trial from 1993 to 1994. A randomized complete design was laid out in 6 treatments with three replications.

Imidacloprid in processed tea and tea liquor

Imidacloprid 是最新介绍的用途广泛的 chloronicotinyl 杀虫药剂并且将在农业生产发现它的方法，特别地在亚洲。然而，在庄稼植物的 imidacloprid 的命运的信息正在缺乏。在处理 CTCtea 和茶白酒的 imidacloprid 的降级在 imidacloprid 以推荐申请率(30.0 g a.i./ha ) 并且两次在被使用的现在的学习被调查为三个连续季节的推荐申请率(60.0 ga.i./ha ) 。Imidacloprid 很快在申请评估的根本首先跟随顺序反应动力学的处理的茶被驱散并且有在茶白酒的残余发现了在第三件天样品上的可检测的限制下面的 0.91-1.16 dwith 的一半生活。学习表明 imidacloprid 为人的消费是安全的并且不提出任何剩余毒性问题。

In vitro acute cytotoxicity of neonicotinoid insecticide imidacloprid to gill cell line of flounder Paralichthy olivaceus

In vitro acute cytotoxicity of neonicotinoid insecticide imidacloprid (IMI) to the gill cell line of flounder (FG) that collected in the gill of Paralichthys olivaceus, was examined by 3 widely used endpoint bioassays: NR (neutral red), MTT (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) and TCP (total cell protein). The result shows that the IMI increased at concentrations ≥0.5 μg/ml. The IC50 value of NR, MTT, and TCP was 41.86, 38.46, and 39.08 μg/ml, respectively. The ultrastructural observation revealed that the mitochondria of the cells exposed to 60 μg/ml IMI for 48 h were severely damaged, swollen or disrupted, while their nuclei and rough endoplasmic reticulum (RER) remained normal. This would suggest that the mitochondria are probably the primary target of IMI.

Technological Optimization of the Preparation of Imidacloprid

In order to reduce the production cost of imidacloprid, the preparation technology for the direct combination of 2-chloro-5-chloromethylpyridine and 2-nitryliminoglyoxaline has been optimized in a 10L stirred tank reactor with a new solvent, butanone, and a new catalyst, benzyl triethyl-ammonium chloride (BTEAC), which was proved to be more profitable for the production of imidacloprid. Three main affecting factors (the reaction temperature, the molar ratio of BTEAC to 2-nitryliminoglyoxaline and the concentration of 2-nitryliminoglyoxaline) for the production of imidacloprid were investigated and the optimum operating conditions were found. Based on the above technological optimization, an industrial process for imidacloprid with a production capacity of 50 tons per year was put in operation using a 2500 L stirred tank reactor under the same operating conditions. Good yield and purity of imidacloprid was also obtained ia the industrial production.

吡虫啉和啶虫脒胶体金免疫层析法试纸条性能评估及应用效果探究

目的研究吡虫啉和啶虫脒胶体金免疫层析法试纸条在不同基质中残留量检测的应用效果。方法实验考察了市场上主要流通的5种不同品牌的胶体金免疫层析法试纸条在蔬菜、水果和茶鲜叶基质中的检出限、灵敏度、交叉反应率、特异性、假阳性和假阴性率。结果各品牌胶体金试纸条在3种不同类型基质(白菜、苹果和茶鲜叶)中,检出限浓度水平有假阴性出现,其余浓度水平灵敏度较好;特异性和交叉反应性,结果均为阴性;假阳性率和假阴性率考察中,假阳性率为0%,但有假阴性情况出现。结论胶体金免疫层析法在检测吡虫啉、啶虫脒农药残留时具有简便快捷的特点,在蔬菜、水果基质的检测中,判定结果较为准确可靠;在茶叶基质中,由于基质效应的影响,出现假阴性的机率较高。

吡虫啉胁迫对红光熊蜂抗氧化酶系与解毒酶系的影响

为探究亚致死剂量吡虫啉胁迫对红光熊蜂工蜂的存活率、解毒酶活力与解毒基因表达量的影响,采用cDNA末端快速扩增技术(RACE)克隆红光熊蜂工蜂(21日龄)解毒基因,检测其表达量变化与抗氧化酶的活性,并通过饲喂外源褪黑素以提高熊蜂的抗药性.结果表明:随着胁迫时间的延长,吡虫啉处理组(IMI组)存活率显著下降,但始终低于吡虫啉+褪黑素处理组(IMI+MT组);IMI组4种抗氧化酶的活性均随吡虫啉胁迫时间的延长呈先上升后下降的趋势,始终低于IMI+MT组;IMI组8种解毒基因的表达量除AChE,DDTase和GLD基因外,其余表达量均随吡虫啉胁迫时间的延长呈先激活后抑制的状态,且明显高于对照组(CK组)而低于IMI+MT组;IMI组DDTase基因的表达量与CK组差异不明显,但始终低于IMI+MT组,说明吡虫啉对DDTase的作用不明显,而褪黑素诱导DDTase表达效果较显著(P<0.05);IMI组AChE和GLD基因的表达量均低于CK组,随吡虫啉胁迫时间的延长而呈下降趋势,但IMI+MT组二者的表达量始终高于IMI组.短期亚致死剂量吡虫啉胁迫对红光熊蜂影响不显著,长期胁迫则影响其存活率,红光熊蜂对吡虫啉的代谢解毒是一个多酶系、多基因协同参与的理化过程,褪黑素可提高红光熊蜂的抗药性.

科学研究与化学综合实验相融合的实验教学——吡虫啉农药的电化学检测

将石墨烯与壳聚糖复合材料修饰到玻碳电极表面,制备对吡虫啉具有特异性响应的电化学传感器,可对样品中吡虫啉的浓度进行定量分析检测。电分析涉及物理化学及分析化学的多个知识,将电化学传感器检测吡虫啉农药科学研究实验融入到本科化学综合实验中,不仅可以提高学生对电化学及分析化学相关理论知识的理解,同时还可以使学生了解科学前沿,培养学生的科学研究兴趣以及创新创造能力。

低浓度吡虫啉削弱多异瓢虫对棉花植株挥发物的嗅觉识别功能

【目的】明确低浓度吡虫啉对多异瓢虫Hippodamia variegata成虫嗅觉行为的影响。【方法】采用Y型嗅觉仪测定多异瓢虫成虫在摄入低浓度(LC_(20)和LC_(50))吡虫啉后对健康棉株和棉蚜Aphis gossypii成蚜为害棉株挥发物的行为反应;并通过固相微萃取收集健康棉株和棉蚜成蚜为害棉株的挥发物,以气相色谱-质谱联用仪分析鉴定挥发物成分;进而测试多异瓢虫成虫对棉株挥发物单一组分的选择行为。【结果】未摄入吡虫啉的多异瓢虫成虫对棉蚜成蚜为害的棉株具有显著的正趋性,但对健康棉株和清洁空气均无显著的趋向性;摄入低浓度吡虫啉的多异瓢虫成虫对棉蚜成蚜为害的棉株、健康棉株以及清洁空气均无显著的趋向性。对比健康棉株,从棉蚜成蚜为害棉株的挥发物中鉴定出8种挥发量显著增加的化合物,分别为月桂烯、柠檬烯、1-癸炔、3-蒈烯、(3E)-4,8-二甲基-1,3,7-壬三烯[(3E)-4,8-dimethyl-1,3,7-nonatriene, DMNT]、β-石竹烯、α-葎草烯、(3E, 7E)-4,8,12三甲基十三碳-1,3,7,11-四烯[(3E, 7E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene, TMTT]。利用Y型嗅觉仪测定多异瓢虫成虫对以上8种物质的嗅觉选择行为发现,未摄入吡虫啉的多异瓢虫成虫对TMTT具有显著的正趋性,对其他7种挥发性化合物无显著趋性,而摄入低浓度吡虫啉的多异瓢虫成虫对8种挥发性化合物均无显著正趋性。在行为选择测试中,低浓度吡虫啉处理后的多异瓢虫成虫对棉株挥发物及单一组分的未选择个体数量均显著多于对照组。【结论】研究结果证实低浓度吡虫啉削弱了多异瓢虫成虫对棉花植株挥发物的嗅觉识别功能,为新疆棉田多异瓢虫的保护利用及棉田农药的合理使用提供科学依据。