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Rezistence dřepčíků a stonkových krytonosců na řepce k vybraným insekticidům
Richterová, Terezie
The aim of this thesis is to evaluate the selection of resistance to selected insecticides in populations of flea beetles and stem weevils collected from conventional oilseed rape fields in the Czech Republic during 2021 and 2022. Testing for resistance to the active ingredients lambda-cyhalothrin, tau-fluvalinate and acetamiprid was carried out according to the methods IRAC (Insecticide Resistance Action Committee) No. 011 and 021. The statistical program Polo Plus 2.0 was used to evaluate the tests, the percentage efficiencies, degrees of resistance and lethal doses were determined. Based on the results, it was found that the populations of flea beetles show resistance to lambda-cyhalothrin. Populations of the cabbage stem weevil show resistance to lambda-cyhalothrin and tau-fluvalinate. To the substance acetamiprid, the populations of stem weevils are currently sensitive. It is therefore necessary to apply anti-resistance strategies to these pests in order to prevent further selection of resistance.
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Vliv aplikace insekticidů na slunéčko východní (Harmonia axyridis)
Kintlerová, Jarmila
The diploma thesis was focused on evaluating the influence of selected active ingredients of insecticides used to protect agricultural crops on populations of the invasive species of harlequin ladybird (Harmonia axyridis Pallas, 1773) obtained from various locations within the Czech Republic. Four active ingredients, acetamiprid, indoxacarb, lambda-cyhalothrin and tau-fluvalinate, were tested according to the IRAC methodology on populations of adult individuals collected at seven locations. The experiment was done in the form of adult vial test, with subsequent evaluation using the Polo Plus 2.0 software. Based on the obtained results of mortality and lethal doses of active ingredients, it was found that the populations were highly sensitive to acetamiprid and lambda-cyhalothrin and sensitive with possible emergence of resistance to tau-fluvalinate. In the case of indoxacarb, populations from three locations showed moderate to high resistance.
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Akutní a chronické působení neonikotinoidových látek na vodní organismy
STROUHOVÁ, Alžběta
Neonicotinoids, synthetic substances derived from the natural alkaloid nicotine, are one of the newest class of pesticides. Neonicotinoids are selective for invertebrate nicotinic acetylcholine receptors (nAChRs) and are widely used to treat crops around the word. The aim of this study was to evaluate acute and chronic toxicity of neonicotinoid substance acetamiprid and neonicotinoid product Mospilan 20 SP, which contains 20 % of acetamiprid, to aquatic organisms. Chronic effects to the biochemical profile of haemolymph, oxidative stress biomarker and antioxidant biomarkers have been evaluated too. Marbled crayfish (Procambarus virginalis) was used as a model organism to provide the toxicity. The acute toxicity (96hLC50) of the pure neonicotinoid substance acetamiprid to marbled crayfish is 0.8 mg.l-1, of Mospilan it is 2.71 mg.l-1. The theoretical acute toxicity of Mospilan is 4.0 mg.l-1. It was calculated based on the acute toxicity of pure acetamiprid as the active substance of Mospilan. Additives in the preparation probably contributes its toxicity more than the active substance itself. Acetamiprid and Mospilan impact on changes in the levels of biomarkers of the biochemical profile of haemolymph, biomarker of oxidative stress and antioxidant biomarkers. Changes in the levels of biomarkers are already manifested at concentrations corresponding to 0,1 % and 1 % of 96hLC50. These changes include increases in GLU, AST, ALT and LDH levels, decreases in CAT and GST activity and changes in LPO level.
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Methodology for assessing the effect of sublethal doses of pesticides on solitary bees\nemploying the OMICs approach
Erban, T. ; Shcherbachenko, E. ; Šlachta, Martin ; Cudlín, Pavel ; Chalupníková, J. ; Halešová, T. ; Tomešová, D. ; Václavíková, M. ; Votavová, A.
Pollinators are potentially exposed to a number of pesticides in the environment. The\nmost important group of hazardous substances comes from the category of plant protection\nproducts (PPPs), which are applied not only by farmers but also by small gardeners. Each PPP\nincluding the active substance and formulation undergoes a very detailed and thorough evaluation,\nwhich is in the European Union (EU) based on Regulation (EC) No 1107/2009 of the European\nParliament and of the Council. Although the negative effects of PPPs on the environment and nontarget organisms are minimized with proper use, we cannot rule out possible hidden effects,\nespecially those of a sublethal nature. Modern analytical approaches, such as the application of\nhigh-throughput methods, help to identify hidden side effects. This methodology is focused on the\nevaluation of the effect of sublethal doses of pesticides on solitary bees employing the OMICs\napproach. In the risk assessment of pesticides, the honey bee has long been preferred as a model\nspecies of pollinator, while solitary bees stay in the background. The methodology contains\ninnovative aspects for experiments, such as a modified isolator, preparation of plants for exposure,\nthe timing of the experiment, monitoring of active substance distribution or proteomic analysis of\nsolitary bees to identify hidden effects of the test substance or its formulation. In this methodology,\nthe model of the solitary bee, red mason bee (Osmia bicornis), is considered. However, the\nmethodology is also applicable to other, especially related species of solitary bees. The\nmethodology can be used in areas of state administration, private laboratories and research\nactivities in the assessment of environmental risks of pesticides on solitary bees. The\nmethodological procedure can confirm or even eliminate environmental risks when registering new\nproducts or reevaluating existing products. This methodology therefore has the potential for use in\ntesting new substances intended for plant protection before their registration. In an exemplary\nembodiment, the effect of acetamiprid in a Careo sticks formulation was tested. The distribution of\nacetamiprid in the soil substrate and the plant was evaluated. The hazardous metabolite\nacetamiprid IM-2-1 was identified in plant tissues. However, proteomic analysis indicated a very\nlow risk of acetamiprid for O. bicornis. This result is in agreement with the fact that acetamiprid\nhas been assessed by EFSA to be a low risk for bees and is registered in the EU until 28 February\n2033.
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