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Diploma thesis “The resistance of the flea beetles of the genus Phyllotreta and Psylliodes to active substances of insecticides“ is followed of NAZV QJ 1230077 Testing the sensitivity of selected insect pests of Brassicaceae crops to insecticides solved in 2012-2016. In the diploma thesis the sensibility of the flea beetles of genus Phyllotreta and Psylliodes to active substances of pyrethroid insecticides (tau-fluvalinate and lambda-cyhalothrin) and neonicotinoids (thiacloprid) was evaluate. The research was realized in 2017 on the 21 locations in the Czech Republic. The beetles were collected from commercial oil rapeseed?s (Brassica napus L. var. napus) and mustard?s (Sinapis alba) fields. The testing was conducted by laboratory methods of IRAC number 011 and 021, the adult-vital test was used for testing. These methods are known for monitoring pollen beetles (Meligethes spp.), but they are suitable for testing another species of pest of oil rapeseed. The results showed a decrease in the sensitivity to some insecticides.

Diploma thesis is followed of bachelor thesis of the same author out of 2013. The aim of this work was evaluation sensibility of the flea beetles of birth Phyllotreta and Psylliodes to active substances of pyrethroid insecticides (lambda-cyhalothrin, cypermethrin and tau-fluvalinate), neonicotinoids (thiacloprid) and organophosphorous insecticides (chlorpyrifos-ethyl). The research was conducted during 2013 in the 22 locations and in 2014 at 15 sites in the Czech Republic. Beetles were collected from normal commercial oilseed colza and mustard. Testing was conducted by laboratory methods of IRAC number 011, 021 and 025, during testing was used the (adul-vial-test). These metods are determined for monitoring (Meligethes spp.), but also these metods are suitable for testing another kind of pest of colza. Between the compared samples of populations flea beetles were found in some localities differences in their sensitivity to the active used substance. The species spectrum of flea beetles were observed in populations collected in 2012. Index of dominance for individual flea beetles species were determined. P. nigripes (37,26 %), P. atra (35,26 %) and P. nemorum (23,26 %) were eudominant species, P. undulata (3,66 %) subdominant, P. vittula (0,06 %) and P. chrysocephala (0,50 %) subrecedent.

Cílem práce bylo zhodnotit vliv pesticidů na bázi triazinů (účinná látka metribuzin) a pyrethroidů (účinná látka bifenthrin) na kapra obecného (Cyprinus carpio) na základě výsledků testu akutní toxicity a výsledků hematologického a biochemického vyšetření plazmy. Hodnota 96hLC50 pro přípravek Sencor 70 WG (s účinnou látkou 70% metribuzinu) byla 250,2 mg.l-1. U kapra obecného po 96h expozici v koncentraci 250,2 mg.l-1 Sencoru 70 WG došlo k významnému snížení (p<0,01) celkových bílkovin, triglyceridů, laktát dehydrogenázy, anorganického fosfátu, hodnot hemoglobinu, hematokritové hodnoty, středního objemu erytrocytu, počtu leukocytů. a významnému zvýšení (p<0,01)glukózy, amoniaku a vápníku. Hodnota 96hLC50 pro přípravek Talstar 10 EC (s účinnou látkou 100 g.l-1 bifenthrinu) byla 57,5{$\mu$}g.l-1. U kapra obecného po 96h expozici v koncentraci 57,5{$\mu$}g.l-1 Talstaru 10 EC došlo k významnému zvýšení hodnot (p<0,01) u glukózy, amoniaku a aspartát aminotransferázy. Pesticidní přípravek na bázi triazinů Sencor 70WG byl zařazen mezi přípravky, které můžou vyvolat dlouhodobé nepříznivé účinky ve vodním prostředí. Pesticidní přípravek na bázi pyrethroidů Talstar 10 EC byl zařazen mezi přípravky, které jsou vysoce toxické pro ryby.

Pyrethroids are ones of the most used pesticides worldwides. The widespread use and high stability of pyrethroids lead to the assumption of that their occurrence in the environment could be quite frequent. They can reach water ecosystem as pollutants. Residues of pyrethroids are not only detected in the water column, but also in sediments and in fish tissues. The first study was devoted to the product Nexide containing 60 g.l-1 of active substance gamma-cyhalothrin. Tested Nexide concentrations were 5, 25, 50, 100, and 250 &microg.l-1. Early life stage test was used.Common carp (Cyprinus carpio) was tested. There were significant mortalities in all concentrations except the lowest concentration during the trial. The lowest concentration tested 5 &microg.l-1 only caused a slightly increased mortality. This lowest concentration influenced the growth in length and weight negatively, decelerated ontogenetic development, and made the body surface of the individuals darker. Histopathology of individuals from this concentration revealed dystrophy in liver. Examination of kidney, intestine and gills did not show significant histopathological differences compared with control. The evaluation of selected parameters of oxidative stress demonstrated a significantly higher activity of detoxification enzyme glutathione-S.transferase (GST) and a significantly lower activity of defensive enzyme glutathione peroxidase (GPx) compared with the control group. The other examined parameters of oxidative stress such as catalase (CAT), glutation reductase (GR), and lipid peroxidation determined by using the thiobarbituric acid-reactive substances (TBARs) were comparable to the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Nexide in the given concentration leads to dysbalance of defensive enzymes. The second study was devoted to the product Cyperkill 25 EC containing 250 g.l-1. Tested Cyperkill 25 EC concentrations were 7.2, 36, 72, 144, and 360 &microg.l-1. The procedure of the trial was the same as the preceded one. There were 100% mortalities in all concentrations except the lowest concentration during the trial. The lowest tested concentration 7.2 &microg.l-1 allowed 90% of individuals to stay alive till the end of experiment. The lowest concentration influenced the growth in length and weight negatively and decelerated ontogenetic development compared with the control. Any individual exposed to this concentration did not reach juvenile stage until the end of the trial. Dark pigmentation was visible in 68% of these exposed individuals on the last day. Similar darkening was visible in individuals from higher concentrations shortly before death too. Histological examination did not revealed significant changes in intestine, liver, kidney, and gills compared with the control group. Evaluation of selected parameters of oxidative stress demonstrated significantly lower activities of GST, GR, and GPx. Activities of CAT and TBARS were comparable with the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Cyperkill 25 EC in the given concentration could induce oxidative stress and interfere with the activities of antioxidant enzymes. The presented thesis summarises actual data about pyrethroids and their influence on fish. The demonstrated effects confirm high susceptibility of early developmental stages of fish to tested pesticides. When interpreting the results, we have to take into account the fact that studies showed this risk even on single pyrethroid substances. But water organisms are exposed to many other more or less toxic products and substances in a real environment. These xenobiotics could react with each other and their mixture could even potentiate negative effects. The performed studies also clearly show the significant differences in the sensitivity of embryonic and embryolarval tests.