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.

Translocation and Distribution of Imidacloprid in Tobacco with Two Application Methods

[Objective] To compare the translocation and distribution of imidacloprid in tobacco with spray and root irrigation application methods. [Methods] Pot experiment in the greenhouse was carried out, and LC-MSMS was used to determine the con- tent of imidacloprid in different parts of tobacco plants （roots, stems, the upper, middle and lower leaves） at different time. [Results] The imidacloprid could be absorbed by root and could be transported to all parts of the tobacco plant after irrigating root, but the original deposition amount was larger and the transport efficiency was lower after spraying. [Conclusion] The translocation and distribution of imidacloprid by spraying was more uniform and the holding efficiency was better, but imidacloprid with root irrigation could act on leaf directly, and had better readily availability.

Effect of Different Concentrations of Pesticide-Imidacloprid on the Main Secondary Metabolites of Fruit and Polysaccharide of Chinese Wolfberry

[Objective] The aim was to seek the appropriate utilization methods for imidacloprid pesticide in the production of Chinese wolfberry,as well as to provide scientific basis for the rational use of imidacloprid pesticide. [Method] The effect of different concentrations and spraying times of 10% WP of imidacloprid on the main secondary metabolites such as carotenoid and flavone,as well as the polysaccharide and total sugar content was studied in field. [Result] The effect of different concentrations of imidacloprid on the secondary metabolites and the content of polysaccharide of Chinese wolfberry was significant. After imidacloprid spraying,the contents of flavone,polysaccharide and total sugar on the 1st,7th and 14th d showed increasing trend,while the content of carotenoid showed decreasing trend. With the dilution times increasing,the content of the flavone,polysaccharide and total sugar showed increasing trend,while the content of carotenoid decreased,in which the highest content of the secondary metabolites and polysaccharide appeared in 1 800 times. [Conclusion] The dilution ratio of 1 800 times should be selected as the appropriate dosage of 10% WP of imidacloprid.

Study on the Degradation Dynamics of Spraying Imidacloprid and Buprofezin before and After Mango Bagging

The four treatments of spraying water the control, spraying before bagging, spraying after bagging, spraying without bagging were conducted by spraying 38% of the mixed suspension agent of imidacloprid and buprofezin, and high performance liquid chromatography （HPLC） method was used to test the imidacloprid and buprofezin residues on mango. The results showed that in 0.05-0.5 mg/kg adding level, the average recovery rate of imidacloprid and buprofezin was 82.6-93.8%, and 101.4-104.2%, respectively, and the relative deviation （RSD） was 1.9-4.5%, 9.3-15.6%, respectively. The minimum detectable amounts of both imidacloprid and buprofezin on mango were 0.01 mg/kg. The half-life periods of imidacloprid under the treatments of spraying before bagging, spraying after bagging and spraying without bagging were 16.74, 6.38, and 8.10 d, respectively, and the half-life periods of buprofezin under the treatments of spraying before bagging and spraying without bagging were 9.72 and 9.23 d, respectively. The residual of buprofezin was low in the treatment of spraying after bagging, and the amount detected in the 3rd day had already below the detectable limit. Bagging treatment reduced the digestion rate of 2 kinds of pesticides in mango, and imidacloprid had strong systemic in mango.

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.

Imidacloprid in processed tea and tea liquor

Imidacloprid is a newly introduced broad-spectrum chloronicotinyl insecticide and will find its way in agricultural production, particularly in Asia. However, information on the fate of imidacloprid in crop plants is lacking. The degradation of imidaclopnd in processed CTC tea and tea liquor was investigated in the present study in which imidacloprid was applied at recommended application rate （30.0 g a.i./ha） and twice the recommended application rate （60.0 g a.i./ha） for three consecutive seasons. Imidacloprid was rapidly dissipated in processed tea following first order reaction kinetics at all application rates and had half-lives of 0.9 1-1.16 d with the residue in tea liquor found to be below detectable limit on 3rd day samples. The study revealed that imidacloprid is safe for human consumption and will not pose any residual toxicity problem.

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.

Effects of 5% Imidacloprid Oil in Preventing Myzus persicae in Different Test Sites

In the research, 5% imidacloprid oil at different doses were applied to prevent Myzus persicae in order to explore significance analysis in 3, 7, 14, and 20 d, respectively, in three fields, and the results showed that 5% imidacloprid oil per- formed significant for K326, G28 and Yunyan-87, suggesting 5% imidacloprid oil is effective in controlling Myzus persicae.

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 ofParalichthys olivaceus, was examined by 3 widely used endpoint bioassays： NR （neutral red）, MTT （3-（4,5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazoliurn bromide） and TCP （total cell protein）. The result shows that the IMI increased at concentrations ≥0.5 μg/ml. The ICs0 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 reticulurn （RER） remained normal. This would suggest that the mitochondria are probably the primary target of IMI.

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...

Technological Optimization of the Preparation of Imidacloprid

In order to reduce the production cost of imidacloprid, the preparation technology for the direct com-bination of 2-chloro-5-chloromethylpyridine and 2-nitryliminoglyoxaline has been optimized in a 10 L 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 temper-ature, the molar ratio of BTEAC to 2-nitryliminoglyoxaline and the concentration of 2-nitryuminoglyoxaline) 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 in the industrial production.

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.

Persistence of Imidacloprid and β-Cyfluthrin Residue in Black Pepper （Piper Nigrum L.） under Malaysia Climatic Condition

Persistence behavior of imidacloprid and beta-cyfluthrin in black pepper was studied following application of formulation of Solomon at 0.6 （recommended dose） and 1.2 （double recommended dose） g a.i./ha for one pepper production cycle. The results also showed that the Solomon at 0.6 mL/L concentration significantly suppressed the pest infestation in pepper vines. Pepper vine treated with Solomon produce more berries compared to control and showed no phytotoxicity. Analytical procedure of Solomon active ingredient was validated prior to actual analysis. Satisfactory recoveries ranging between 87.6%-106.7% were obtained for the fortified pepper berries samples. Results showed low level of imidacloprid and beta-cyfluthrin residues in dried pepper berries ranging between 〈 0.01 mg/kg to 1.43 mg/kg and 〈 0.01 mg/kg to 1.612 mg/kg respectively. The half-life value period for imidacloprid were found to be 2.06 and 2.30 days and for beta-cyfluthrin, these values were observed to be 1.57 and 1.49 days respectively at recommended and double recommended dose. Imidacloprid and beta-cyfluthrin residue dissipated below the limit of quantification （LOQ） of 0.01 mg/kg after 7 and 9 days respectively at recommended and double recommended dose. Soil sample collected 15 days after the last spray did not show the present of Imidacloprid and beta-cyfluthrin residue at their detection limit of 0.01 mg/kg.

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.