This work was supported by the National Natural Science Foundation of China (No. 42277039).

1. Germination of wheat seeds
<ol>
	<li>Select 1,000 wheat seeds (Jimai 20) with complete granules, intact embryos, and uniform size (length: 6 mm &#177; 0.5 mm).</li>
	<li>Transfer 333.3 mL of 30% H2O2 solution to a 1 L volumetric flask and dilute with deionized water to prepare 1 L of 10% H2O2 solution. Immerse the wheat seeds in 10% H2O2 solution for 15 min to disinfect the seed surface (Figure 1).</li>
	...

<ol>
	<li>Lin, P. C., Lin, H. J., Liao, Y. Y., Guo, H. R., Chen, K. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acute+poisoning+with+neonicotinoid+insecticides:+A+case+report+and+literature+review.">Acute poisoning with neonicotinoid insecticides: A case report and literature review.</a> Basic &amp; Clinical Pharmacology &amp; Toxicology. 112 (4), 282-286 (2013).</li><li>North, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Value+of+neonicotinoid+insecticide+seed+treatments+in+Mid-South+corn+(Zea+mays)+production+systems.">Value of neonicotinoid insecticide seed treatments in Mid-South corn (Zea mays) production systems.</a> Journal of Economic Entomology. 111 (1), 187-192 (2018).</li><li>Simon-Delso, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Systemic+insecticides+(neonicotinoids+and+fipronil):+Trends,+uses,+mode+of+action+and+metabolites.">Systemic insecticides (neonicotinoids and fipronil): Trends, uses, mode of action and metabolites.</a> Environmental Science and Pollution Research. 22 (1), 5-34 (2015).</li><li>Bass, C., Denholm, I., Williamson, M. S., Nauen, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+global+status+of+insect+resistance+to+neonicotinoid+insecticides.">The global status of insect resistance to neonicotinoid insecticides.</a> Pesticide Biochemistry and Physiology. 121, 78-87 (2015).</li><li>Craddock, H. A., Huang, D., Turner, P. C., Quiros-Alcala, L., Payne-Sturges, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trends+in+neonicotinoid+pesticide+residues+in+food+and+water+in+the+United+States,+1999-2015.">Trends in neonicotinoid pesticide residues in food and water in the United States, 1999-2015.</a> Environmental Health. 18 (1), 7 (2019).</li><li>Shao, X. S., Liu, Z. W., Xu, X. Y., Li, Z., Qian, X. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overall+status+of+neonicotinoid+insecticides+in+China:+Production,+application+and+innovation.">Overall status of neonicotinoid insecticides in China: Production, application and innovation.</a> Journal of Pesticide Science. 38 (1-2), 1-9 (2013).</li><li>Zhao, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Urinary+neonicotinoid+insecticides+in+children+from+South+China:+Concentrations,+profiles+and+influencing+factors.">Urinary neonicotinoid insecticides in children from South China: Concentrations, profiles and influencing factors.</a> Chemosphere. 291, 132937 (2022).</li><li>Kurwadkar, S., Evans, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neonicotinoids:+Systemic+insecticides+and+systematic+failure.">Neonicotinoids: Systemic insecticides and systematic failure.</a> Bulletin of Environmental Contamination and Toxicology. 97 (6), 745-748 (2016).</li><li>Sadaria, A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Passage+of+fiproles+and+imidacloprid+from+urban+pest+control+uses+through+wastewater+treatment+plants+in+northern+California,+USA.">Passage of fiproles and imidacloprid from urban pest control uses through wastewater treatment plants in northern California, USA.</a> Environmental Toxicology and Chemistry. 36 (6), 1473-1482 (2017).</li><li>Damalas, C. A., Eleftherohorinos, I. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pesticide+exposure,+safety+issues,+and+risk+assessment+indicators.">Pesticide exposure, safety issues, and risk assessment indicators.</a> International Journal of Environmental Research and Public Health. 8 (5), 1402-1419 (2011).</li><li>Hayes, T. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Demasculinization+and+feminization+of+male+gonads+by+atrazine:+Consistent+effects+across+vertebrate+classes.">Demasculinization and feminization of male gonads by atrazine: Consistent effects across vertebrate classes.</a> Journal of Steroid Biochemistry and Molecular Biology. 127 (1-2), 64-73 (2011).</li><li>Rani, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+extensive+review+on+the+consequences+of+chemical+pesticides+on+human+health+and+environment.">An extensive review on the consequences of chemical pesticides on human health and environment.</a> Journal of Cleaner Production. 283, 124657 (2021).</li><li>Xu, Y. Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ecotoxicity+evaluation+of+azoxystrobin+on+Eisenia+fetida+in+different+soils.">Ecotoxicity evaluation of azoxystrobin on Eisenia fetida in different soils.</a> Environmental Research. 194, 110705 (2021).</li><li>Yavari, S., Malakahmad, A., Sapari, N. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochar+efficiency+in+pesticides+sorption+as+a+function+of+production+variables-A+review.">Biochar efficiency in pesticides sorption as a function of production variables-A review.</a> Environmental Science and Pollution Research. 22 (18), 13824-13841 (2015).</li><li>Delcour, I., Spanoghe, P., Uyttendaele, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Literature+review:+Impact+of+climate+change+on+pesticide+use.">Literature review: Impact of climate change on pesticide use.</a> Food Research International. 68, 7-15 (2015).</li><li>Zhang, C. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+application+of+the+QuEChERS+methodology+in+the+determination+of+antibiotics+in+food:+A+review.">The application of the QuEChERS methodology in the determination of antibiotics in food: A review.</a> TrAC-Trends in Analytical Chemistry. 118, 517-537 (2019).</li><li>Wiilkowska, A., Biziuk, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+pesticide+residues+in+food+matrices+using+the+QuEChERS+methodology.">Determination of pesticide residues in food matrices using the QuEChERS methodology.</a> Food Chemistry. 125 (3), 803-812 (2011).</li><li>Ishii, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HPLC+determination+of+the+new+insecticide+imidacloprid+and+its+behavior+in+rice+and+cucumber.">HPLC determination of the new insecticide imidacloprid and its behavior in rice and cucumber.</a> Journal of Agricultural and Food Chemistry. 42 (12), 2917-2921 (1994).</li><li>Ko, A. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+simple+extraction+and+oxidation+procedure+for+the+residue+analysis+of+imidacloprid+and+its+metabolites+in+lettuce+using+gas+chromatography.">Development of a simple extraction and oxidation procedure for the residue analysis of imidacloprid and its metabolites in lettuce using gas chromatography.</a> Food Chemistry. 148, 402-409 (2014).</li><li>Yuan, W. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+imidacloprid+controlled-release+granules+to+enhance+the+utilization+rate+and+control+wheat+aphid+on+winter+wheat.">Application of imidacloprid controlled-release granules to enhance the utilization rate and control wheat aphid on winter wheat.</a> Journal of Integrative Agriculture. 19 (12), 3045-3053 (2020).</li><li>Phugare, S. S., Kalyani, D. C., Gaikwad, Y. B., Jadhav, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbial+degradation+of+imidacloprid+and+toxicological+analysis+of+its+biodegradation+metabolites+in+silkworm+(Bombyx+mori).">Microbial degradation of imidacloprid and toxicological analysis of its biodegradation metabolites in silkworm (Bombyx mori).</a> Chemical Engineering Journal. 230, 27-35 (2013).</li><li>Li, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uptake,+translocation+and+accumulation+of+imidacloprid+in+six+leafy+vegetables+at+three+growth+stages.">Uptake, translocation and accumulation of imidacloprid in six leafy vegetables at three growth stages.</a> Ecotoxicology and Environmental Safety. 164, 690-695 (2018).</li><li>Badawy, M. E. I., Ismail, A. M. E., Ibrahim, A. I. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+analysis+of+acetamiprid+and+imidacloprid+residues+in+tomato+fruits+under+greenhouse+conditions.">Quantitative analysis of acetamiprid and imidacloprid residues in tomato fruits under greenhouse conditions.</a> Journal of Environmental Science and Health Part B-Pesticides Food Contaminants and Agricultural Wastes. 54 (11), 898-905 (2019).</li><li>Zhai, R. Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Residue,+dissipation+pattern,+and+dietary+risk+assessment+of+imidacloprid+in+Chinese+chives.">Residue, dissipation pattern, and dietary risk assessment of imidacloprid in Chinese chives.</a> Frontiers in Nutrition. 9, 846333 (2022).</li><li>Aria, M. 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The authors declare that they have no conflicts of interest. All the authors have read and approved the manuscript. This work has not been published previously, nor is it being considered by any other peer-reviewed journal.

In recent years, methods for the pretreatment and detection of residues of the pesticide imidacloprid have been frequently reported. Badawy et al.23 used high-performance liquid chromatography to determine the content of imidacloprid in tomato fruit grown under greenhouse conditions and reported good linearity for imidacloprid in the range 0.0125-0.15 &#181;g/mL. Zhai et al.24 used LC-MS-MS to study the residue of imidacloprid in Chinese chives. In the present study, the Qu...

In present day agronomy, the use of pesticides is essential to increase crop yield. Neonicotinoid insecticides alter the membrane potential balance by controlling nicotinic acetylcholine receptors in the insect nervous system, thereby inhibiting the normal conduction of the insect central nervous system, leading to the paralysis and death of the insects1. Compared with traditional insecticides, neonicotinoids have advantages such as novel modes of action, high insecticidal activity, and strong root absorption, making them highly successful in the pesticide market2,3. The sales volume of neonicotinoids was reported to account for 27% of the world pesticide market in 2014. The average annual growth rate of neonicotinoids was 11.4% from 2005 to 2010, of which about 7% was registered in China4,5,6. From the end of 2016 to the first half of 2017, the sales of pesticides in China began to rebound after falling, and the prices of pesticides continued to rise, among which neonicotinoid insecticides showed a significant price increase7. So far, three generations of neonicotinoid insecticides have been developed, each containing pyridine chloride, thiazolyl, and tetrahydrofuran groups of nicotine, respectively8.
Imidacloprid represents the first generation of neonicotinoid insecticides, whose molecular formula is C9H10ClN5O2, and is a colorless crystal. Imidacloprid is used mainly to control pests, such as aphids, planthoppers, mealworms, and thrips9 and can be applied to crops such as rice, wheat, corn, cotton, and vegetables such as potatoes, as well as fruit trees. Due to the long-term, substantial, and continual application of pesticides, both beneficial insects and the natural enemies of pests have been rapidly reduced, and some agricultural pests have become resistant to pesticides, resulting in a vicious circle of applying continual and increasing amounts of pesticides10. In addition, the extensive application of pesticides has led to the deterioration of soil quality, persistent pesticide residues in agricultural products, and other ecological problems, which not only cause significant damage to the agricultural ecological environment11 but also pose a serious threat to human health12. Pesticide spraying severely impacts the growth and quality of soil microbes and soil animals13. The unreasonable or excessive use of pesticides has caused significant security risks to the soil and water environment, animals and plants, and even human life14. In recent years, the problem of excessive pesticide residues in crops has become more severe with the extensive application of pesticides. When imidacloprid was used to increase vegetable yield, the absorption rate of imidacloprid in the vegetables increased with the increase in the amount and residue of imidacloprid15. As a major food crop, both the production and safety of wheat are critical. Therefore, the residue and distribution policies of pesticides used for wheat need to be clarified.
In recent years, many methods have been developed to extract imidacloprid residues from water, soil, and plants. The QuEChERS method (quick, easy, cheap, effective, rugged, and safe) is a new method that combines solid-phase microextraction technology and dispersed solid-phase extraction technology and involves the use of acetonitrile as the extraction solvent and the removal of mixed impurities and water in the sample using NaCl and anhydrous MgSO4, respectively16. The QuEChERS method requires minimal glassware and has simple experimental steps, making it one of the most popular pesticide extraction methods17. For the detection of imidacloprid, a detection limit as low as 1 &#215; 10&#8722;9 g18 has been achieved with liquid chromatography (LC), and 1 &#215; 10&#8722;11 g19 has been achieved with gas chromatography (GC). Due to their high resolution and sensitivity, LC-MS and GC-MS have shown even lower imidacloprid detection limits of 1 &#215; 10-13 to 1 &#215; 10-14 g20,21; these techniques are, therefore, well suited for the analysis of trace imidacloprid residues.
In the present study, imidacloprid was chosen as the target pollutant, and wheat was selected as the test crop to study the distribution of imidacloprid residues in wheat. This protocol details a method for the comprehensive analysis of the enrichment and transfer of the pesticide imidacloprid in wheat by exploring the absorption and storage of imidacloprid in different parts of wheat plants grown under hydroponic conditions. The present study aims to provide a theoretical basis for the risk assessment of pesticide residues in wheat, guide the rational application of pesticides in agricultural production activities to reduce pesticide residues, and improve the safety of crop production.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Acetonitrile</td>
			<td>Sigma-Aldrich (Shanghai) Trading Co. Ltd.</td>
			<td>01-06-1995</td>
			<td>Suitable for HPLC, gradient grade, &#62;99.9%</td>
		</tr>
		<tr>
			<td>Analytical balance</td>
			<td>Sartorius Lab Instruments Co.Ltd.</td>
			<td>GL124-1SCN</td>
			<td></td>
		</tr>
		<tr>
			<td>Artificial climate incubator&#160;&#160;</td>
			<td>Shanghai Badian Instrument Equipment Co. Ltd.</td>
			<td>HK320</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge</td>
			<td>Eppendorf China Co. Ltd.</td>
			<td>Centrifuge5804</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable syringe</td>
			<td>Sigma-Aldrich (Shanghai) Trading Co. Ltd.</td>
			<td>Z116866</td>
			<td>Capacity 5 mL, graduated 0.2 mL, non-sterile</td>
		</tr>
		<tr>
			<td>Formic acid</td>
			<td>Sigma-Aldrich (Shanghai) Trading Co. Ltd.</td>
			<td>Y0001970</td>
			<td>European pharmacopoeia reference standard</td>
		</tr>
		<tr>
			<td>Graphitized carbon black (GCB)</td>
			<td>Sigma-Aldrich (Shanghai) Trading Co. Ltd.</td>
			<td>V900058</td>
			<td>45 &#956;m</td>
		</tr>
		<tr>
			<td>H2O2</td>
			<td>Sigma-Aldrich (Shanghai) Trading Co.Ltd.</td>
			<td>31642</td>
			<td>30% (w/w)</td>
		</tr>
		<tr>
			<td>Hoagland&#8217;s Basal Salt Mixture</td>
			<td>Shanghai Yu Bo Biotech Co. Ltd.</td>
			<td>NS1011</td>
			<td>Anhydrous, reagent grade</td>
		</tr>
		<tr>
			<td>Hydroponic equipment</td>
			<td>Jiangsu Rongcheng Agricultural Science and Technology Development Co.Ltd.</td>
			<td>SDZ04BD</td>
			<td></td>
		</tr>
		<tr>
			<td>Hypersil BDS C18 column</td>
			<td>Thermo Fisher Scientific (China) Co. Ltd.</td>
			<td>28103-102130</td>
			<td></td>
		</tr>
		<tr>
			<td>Imidacloprid</td>
			<td>Sigma-Aldrich (Shanghai) Trading Co. Ltd.</td>
			<td>Y0002028</td>
			<td>European pharmacopoeia reference standard</td>
		</tr>
		<tr>
			<td>MgSO4</td>
			<td>Sigma-Aldrich (Shanghai) Trading Co. Ltd.</td>
			<td>208094</td>
			<td>Anhydrous, reagent grade, &#62;97%</td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>Sigma-Aldrich (Shanghai) Trading Co.Ltd.</td>
			<td>S9888</td>
			<td>Reagent grade, 99%</td>
		</tr>
		<tr>
			<td>pH meter</td>
			<td>Shanghai Thunder Magnetic Instrument Factory</td>
			<td>PHSJ-3F</td>
			<td></td>
		</tr>
		<tr>
			<td>Phytotron box</td>
			<td>Harbin Donglian Electronic Technology Co. Ltd.</td>
			<td>HPG-280B</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipettes</td>
			<td>Eppendorf China Co. Ltd.</td>
			<td>Research plus</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe filter</td>
			<td>Sigma-Aldrich (Shanghai) Trading Co.Ltd.</td>
			<td>SLGV033N</td>
			<td>Nylon, 0.22 &#181;m pore size, 33 mm, non-sterile</td>
		</tr>
		<tr>
			<td>Ultra performance liquid chromatography tandem triple quadrupole mass spectrometry</td>
			<td>Thermo Fisher Scientific (China) Co. Ltd.</td>
			<td>UltiMate 3000</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td>TSQ Quantum Access MAX</td>
			<td></td>
		</tr>
		<tr>
			<td>Vortex mixer</td>
			<td>Shanghai Yetuo Technology Co. Ltd.</td>
			<td>Vortex-2</td>
			<td></td>
		</tr>
		<tr>
			<td>Wheat seed</td>
			<td>LuKe seed industry</td>
			<td></td>
			<td>Jimai 20</td>
		</tr>
	</tbody>
</table>

determination of the absorption, translocation, and distribution of imidacloprid in wheat

Neonicotinoids, a class of insecticides, are widely used because of their novel modes of action, high insecticidal activity, and strong root uptake. Imidacloprid, the most widely used insecticide worldwide, is a representative first-generation neonicotinoid and is used in pest control for crops, vegetables, and fruit trees. With such a broad application of imidacloprid, its residue in crops has attracted increasing scrutiny. In the present study, 15 wheat seedlings were placed in a culture medium containing 0.5 mg/L or 5 mg/L imidacloprid for hydroculture. The content of imidacloprid in the wheat roots and leaves was determined after 1 day, 2 days, and 3 days of hydroculture to explore the migration and distribution of imidacloprid in wheat. The results showed that imidacloprid was detected both in the roots and leaves of the wheat plant, and the content of imidacloprid in the roots was higher than that in the leaves. Furthermore, the imidacloprid concentration in the wheat increased with increasing exposure time. After 3 days of exposure, the roots and leaves of the wheat in the 0.5 mg/L treatment group contained 4.55 mg/kg &plusmn; 1.45 mg/kg and 1.30 mg/kg &plusmn; 0.08 mg/kg imidacloprid, respectively, while the roots and leaves of the 5 mg/L treatment group contained 42.5 mg/kg &plusmn; 0.62 mg/kg and 8.71 mg/kg &plusmn; 0.14 mg/kg imidacloprid, respectively. The results from the present study allow for a better understanding of pesticide residues in crops and provide a data reference for the environmental risk assessment of pesticides.

The instrument limit of detection (LOD) of imidacloprid was 5.76 &#215; 10&#8722;14 g, and the method&#39;s LOD of imidacloprid in the wheat root or leaf was 0.01 &#181;g/kg; no matrix effect was observed. The recovery yields of imidacloprid in wheat are shown in Table 2. The recovery yields of imidacloprid from the wheat roots exposed to imidacloprid concentrations of 0.5 mg/L and 5 mg/L were 94.0%-97.6% and 98.8%-99.2%, respectively; the coefficients of variation were 1.92% and 0.20%, respec...

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Determination of the Absorption, Translocation, and Distribution of Imidacloprid in Wheat

Presented here is a protocol for the determination of the absorption, translocation, and distribution of imidacloprid in wheat under hydroponic conditions using liquid chromatography-tandem mass spectrometry (LC-MS-MS). The results showed that imidacloprid can be absorbed by wheat, and imidacloprid was detected in both the wheat roots and leaves.

Neonicotinoids, a class of insecticides, are widely used because of their novel modes of action, high insecticidal activity, and strong root uptake. ...

This method helps to answer how Imidacloprid is absorbed, transported, and distributed in wheat. The main advantage of this technique is the high sensitivity of imidacloprid detection, which can be widely used to determine imidacloprid in soil, water, plant, and other samples. To germinate the wheat seeds, select 1000 suitable seeds having complete granules, intact embryos, and uniform size.Immerse the seeds in 10%hydrogen peroxide solution for 15 minutes to disinfect their surfaces. Then rinse the seeds five times by running sterile water for 10 seconds each time. Now, spread the wheat seeds evenly with the embryos pointing up in a glass Petri dish containing moist, sterile filter paper.Place the Petri dish in an artificial climate incubator maintained at 30 degrees Celsius and 80%relative humidity. Culture the wheat seeds in the dark for three days until they germinate and develop roots. After the wheat seeds have germinated, place 15 wheat seedlings in a hydroponic apparatus containing 100 milliliters of half Hoaglands nutrient solution.Then, place the entire hydroponic setup in an artificial climate incubator at 25 degrees Celsius and 80%relative humidity for seven days. To set up the pesticide exposure experiments with two different imidacloprid concentrations, prepare hydroponic devices containing half Hoaglands nutrient solution with either 0.5 milligrams per liter or five milligrams per liter of imidacloprid. Set up 15 hydroponic devices for each imidacloprid concentration group to ensure adequate samples during sampling.Now, transplant 15 wheat plants post their seven-day hydroponic period into each prepared hydroponic device. Place the entire hydroponic setup in an artificial climate incubator for three days at 25 degrees Celsius and 80%relative humidity. Throughout the imidacloprid exposure period, collect roots and leaves from the plants daily.For each imidacloprid concentration, integrate the wheat samples from every fifth of the 15 hydroponic devices as a parallel group. To extract imidacloprid from wheat roots, shred the wheat roots using scissors into approximately one centimeter pieces. Weigh 10 grams of the shredded wheat roots and place them in a 50 milliliter centrifuge tube.Then, add 10 milliliters of acetyl nitrile to the centrifuge tube and vortex the tube for one minute before adding four grams of anhydrous magnesium sulfate and 1.5 grams of sodium chloride to the tube. Immediately vortex the tube for 30 seconds. Next, centrifuge the tube at 6, 000 G for five minutes.Aspirate the supernatant with a disposable syringe and pass it through a 0.22 micron syringe filter to obtain the sample. To extract imidacloprid from wheat leaves, shred the fresh leaves using scissors into pieces of approximately one centimeter. Weigh 10 grams of the shredded wheat leaves and place them in a 50 milliliter centrifuge tube.Add 10 milliliters of acetonitrile to 10 grams of the shredded wheat leaves in a 50 milliliter centrifuge tube and vortex for one minute. Then treat the mixture with anhydrous magnesium sulfate and sodium chloride, and centrifuge as demonstrated previously. To remove pigmentation and moisture from the sample, take two milliliters of the supernatant obtained after the centrifugation and add it to a five milliliter centrifuge tube containing graphitized carbon black and anhydrous magnesium sulfate.After 30 seconds of vortex mixing, centrifuge the tube at 6, 000 G for five minutes, followed by aspirating the supernatant with a disposable syringe and passing it through a 0.22 micron syringe filter to obtain the sample. Use liquid chromatography tandem mass spectrometry to quantify the amount of imidacloprid from the wheat samples as described in the manuscript. The recovery yields of imidacloprid from wheat samples showed that the average imidacloprid recoveries from wheat roots and leaves exposed to 0.5 milligrams per liter of imidacloprid or lesser compared to the average recoveries from samples exposed to five milligrams per liter of imidacloprid.Imidacloprid was detected in both roots and leaves of wheat plants even after one day of exposure, indicating its rapid absorbance and conductance into the plants. The imidacloprid content was higher on day three of exposure than on day one, and the imidacloprid concentration was consistently higher in the roots than in the leaves. No apparent inhibition of plant growth was observed, even after three days of imidacloprid exposure in plants exposed to imidacloprid as compared to the controls.The root concentration factor, or RCF, in the treated samples was greater than one, indicating wheat has an enrichment effect on imidacloprid. However, the translocation factor, or TF, for leaves was less than one, suggesting that the pesticide was not easily transferred from the wheat roots to the leaves. The most important steps are the extraction and purification of imidacloprid.Ensure that imidacloprid is extracted without loss during these steps.

determination-absorption-translocation-distribution-imidacloprid

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1.2K Views.  Shandong Agricultural University. This method helps to answer how Imidacloprid is absorbed, transported, and distributed in wheat. The main advantage of this technique is the high sensitivity of imidacloprid detection, which can be widely used to determine imidacloprid in soil, water, plant, and other samples. To germinate the wheat seeds, select 1000 suitable seeds having complete granules, intact embryos, and uniform size.Immerse the seeds in 10%hydrogen peroxide solution for 15 minutes to disinfect their surfaces. T...