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ABSTRACT Corpses in Brazil are commonly hidden in sugarcane plantations in the attempt to delay their finding and hinder the solution of the crime. On the other hand, these plantations are regularly sprayed with insecticides for pest control. Until now no study has reported the effects of insecticides on ant fauna. This study aimed to test the hypothesis that if a body hidden in a monoculture is accidentally contaminated by an insecticide, both the carcass decomposition pattern and the Formicidae fauna will be affected. To accomplish this, pig carcasses contaminated and non-contaminated were placed in a sugarcane monoculture environment and subsequently examined for data collection every 24 hours. The concentration used to contaminate the carcasses was 20 grams per liter of thiamethoxam. The decomposition patterns of contaminated carcasses were changed, in turn affecting the behavior of Formicidae fauna. A total of 5318 ants were collected, 3397 in contaminated carcasses and 1919 in non-contaminated carcasses, and 30 species of 11 genera were identified. According to the analysis, there are no differences between the composition of species between contaminated and non-contaminated carcasses, however, a significant difference was observed in the composition of species along the stages of decomposition between the two types of carcasses. Therefore, our hypothesis has been confirmed, contaminated carcasses undergo changes in their normal pattern of decomposition and the fauna of ants that act on them. As this group of insects has great importance for forensic sciences, the analysis of the experts should take these results into account.

The green peach aphid (Myzus persicae) is one of the most common and most harmful species of aphids on the peach in the world. It is a serious problem for many industrial and vegetable crops and vector of various economically important viruses on them. The control of this species of aphids is extremely difficult due to the specific life cycle, the high reproductive potential, the wide range of hosts, the ability to spread rapidly and the development of resistance to different groups of insecticides. A series of field experiments was carried out in the spring of 2016/2017 to improve the control of this species of aphids. The purpose of these experiments was to evaluate and compare the efficacy of spirotetramat (Movento®) used to control M. persicae with that of neonicotinoids imidacloprid or thiamethoxam when applied alone after flowering. The results show that spirotetramat demonstrates excellent efficacy and very good persistance, allowing effective control of M. persicae populations for more than a month. Movento®, applied once after flowering, provides excellent and reliable control of M. persicae populations, significantly superior to that of neonicotinoids imidacloprid and thiamethoxam in terms of efficacy and persistence. Spirotetramat can be considered as a reliable means of controlling M. persicae and a possible alternative to neonicotinoid insecticides to reduce the risk of mass multiplication and resistance occurrence. The best time for its application is after flowering before or in the presence of first visible colonies of M. persicae on the peach shoots. [ABSTRACT FROM AUTHOR]

Sugar beet production remains unprotected after the ban on neonicotinoids, while pest pressure is increasing. Although the organic approach to agriculture is highly welcomed, the question remains whether it will be possible to grow sugar beet without pesticides. The aim of this study is to determine the efficacy of seed treatments with neonicotinoids on the main sugar beet pests, to determine the susceptibility of the pests under the specific climatic conditions and to discuss possible consequences of the ban of neonicotinoids on the future of sugar beet production in southeast Europe. The study was conducted in two different climatic regions in Croatia in two consecutive years. The tested variants were: seed coated with imidacloprid, seed coated with a combination of thiamethoxam and teflutrin and untreated control. Our results showed that seed coatings with imidacloprid and thiamethoxam provided satisfactory protection against wireworms, flea beetles and sugar beet weevils at low population pressure. These pests are regular pests of sugar beet in southern and eastern Europe and therefore need to be controlled. Caterpillars and aphids were present in low populations, so the efficacy of the insecticides tested cannot be determined with certainty. A further research program is needed to find alternative solutions and develop easily implementable strategies for all sugar beet pests. We would propose an authorization of neonicotinoids for seed treatment of sugar beet in the regions with high infestation pressure of the main sugar beet pests.

Vegetable seeds have high commercial value, in the field after sowed seeds were exposed to unfavorable environmental conditions capable of causing reductions in the yield. Thiamethoxam is a bio-activator that may confer tolerance to stresses. In this regard, we aimed to evaluate the influence of thiamethoxam in the physiological performance of four lots of tomato and onion seeds. Seeds were treated with five doses of thiamethoxam, 0.0; 0.2; 0.4; 0.6 and 0.8 ml of product per 1000 seeds. The effects of the seed treatments were evaluated by the assessments of the first count of germination, sprouting test, cold test, accelerated aging and seedling's emergence in the greenhouse. The experimental design was completely randomized, with four replicates per lot and by species. Data were submitted to analysis of variance and adjusted by orthogonal polynomials, using the adjusting equation based on the significance of F test at 5% probability. The bioactivator provided an increase in germination percentage, the first count of ermination, germination after accelerated aging, cold test and seedling's emergence for low vigor seed lots. The bioactivator thiamethoxam stimulates the physiological performance of tomato and onion seeds. Doses of 0.5 to 0.6 mL of thiamethoxam per 1000 seeds of tomato and onion correspond to technical maximum efficiency. [ABSTRACT FROM AUTHOR]

Pesticides are a possible cause of pollinator decline and honey bee colony losses experienced in several countries in recent years. In the past years, many north-west Italian beekeepers reported the presence of dead brood in field apiaries during neonicotinoid-coated maize sowing; therefore, a possible role of these insecticides was suspected. The objective of this study was to test this hypothesis. Laboratory repeated dose toxicity tests on in vitro reared larvae were carried out using thiamethoxam. The repeated treatment median lethal concentration (LC) and the median lethal dose (LD) 14 and 19 days after grafting were calculated and resulted of the same order of magnitude of realistic brood exposure under a worst-case scenario. Various sublethal effects, like brownish larvae, duplication of the pupal integument, delay in development, and deformed adults were also observed. [ABSTRACT FROM AUTHOR]

Fungistatic and toxicity of 3 insecticides including of Thiodicarb (Larvin® 80DF), Thiametoxam (Cruiser® 350DF) and Imidacloprid (Guacho® 70WS) were evaluated on mycelial growth of Trichoderma harzianum Rifai. The experiments were factorial based on a randomized complete design with 18 treatments and 5 replications that were made on M.A 2 % medium containing each of the insecticides at 4, 5, 6, 7, 8 (×103) ppm (Controls were also prepared without any insecticides). Dose-response curves were drawn by plotting mycelial growth inhibition % against the insecticide concentration on log-probit scale and the concentration causing 50 % inhibition (ED50 value) was reported in log µg/ml. All three insecticides inhibited to some extent the growth of T. harzianum, this inhibition was a result of a particular insecticide-fungus combination. Sensitivity of T. harzianum against tested insecticides showed 30.6-77.6 % and 1-9.8 % inhibition of the growth of fungal antagonist with Thiodicarb and Imidacloprid, respectively. In addition, Thiodicarb had more toxicity effect (ED50= 3.74) on fungus than Thiametoxam (ED50=3.89). In greenhouse, treated seeds with 1.5 % Trichodermin B (w/w), 3 recommended dosages of tested insecticides were sown in artificially infected soils with 5, 1 and 6 % (W/V) inoculum of Fusarium moniliforme, Pythium ultimum and Rhizoctonia solani. Experiments confirmed in vitro results so that, Trichodermin B + Imidacloprid (5 and 6 gr of commercial product. Kg-1 cotton seed) provided excellent integrated control against pre- and post-emergence damping-off by 88.9 and 75 %, respectively. It is concluded that Imidacloprid had the least deleterious effects on T. harzianum and could have been used in IPM and sustainable production of cotton.

Simultaneous occurrence of different harmful species in agricultural practice necessitates that different plant protection chemicals be applied at the same time (tank mix). Mix components differ in purpose, mode of action and/or formulation, while addition of nonpesticide components (complex fertilizers, adjuvants and wetting agents) is widely practiced today. However, data concerning the effects of water quality used for preparation of working liquids on the biological effects of pesticides is still scarce. Therefore, the objective of this study was to determine insecticidal effects as depending on components used in mixes and water hardness. The effects of mixtures of thiametoxam (Actara 25-WG 0,07kg/ha) with azoxystrobin (Quadris 0.75 l/ha), mancozeb (Dithane M-70 2.5 kg/ha), a complex fertilizer (Mortonijc plus 3 kg/ha) and a wetting agent (Silwet L-77), depending on the components and water hardness(slightly hard (15.4 d°) - tap water from Novi Sad, and very hard (34.7 d°) - well water from Adica, a Novi Sad suburb), were determined in a bioassay based on adult mortality rate of the first generation of Colorado potato beetle (Leptinotarsa decemlineata Say). The mixtures were applied by a flooding method. The trial was set up to include four replications. Insecticidal effects were determined 24 h and 48 h after exposure. Thiametoxam effectiveness 24 h and 48 h after application in slightly hard water was 100% when the insecticide was applied alone and in double and triple mixes with the fungicides, complex fertilizer and wetting agent, showing no dependency on mix components.The tested adult population of Colorado potato beetle demonstrated high susmceptibility to thiametoxam, while the other components had no impact in slightly hard water. In very hard water, 24 h after application, the insecticidal effect had the same level of significance to thiametoxam in double and triple mixes, with an exception of thiametoxam+mancozeb+Mortonijc plus and thiametoxam+mancozeb+wetting agent combinations, which showed significantly lower efficacy. After 48 h, substantially lowereffectiveness, in comparison with the sole insecticide and other combinations, was only observed in thiametoksam+mancozeb+Mortonjic plus combination. Significantly lower efficacy of that combination is probably due to an incompatibility of the macozeb preparation and the complex fertilizer containing boron (B), which was evidenced only in very hard water.

El minador de la hoja de los citrus Phyllocnistis citrella Stainton es una plaga que daña las hojas de los cítricos por las galerías que realizan las larvas. Las plantas cítricas de vivero y las plantaciones jóvenes de hasta dos años de edad son las más afectadas, ya que presentan continuas brotaciones durante la primavera y el verano. El ataque del minador retrasa el crecimiento de las plantas y altera su estructura. Para el control efectivo de esta plaga se realizan cada 10 a 15 días, aplicaciones foliares con insecticidas durante el período de noviembre a marzo en plantas en vivero. En el presente trabajo se informa el control del minador obtenido con los insecticidas sistémicos imidacloprid y tiametoxan, aplicados en "drench" a plantas de limonero en macetas en vivero. Se evaluaron las siguientes dosis de los insecticidas en una sola aplicación por maceta de 5 l de capacidad: 0,035; 0,105 y 0,175 g de i.a. de imidacloprid y 0,025; 0,075 y 0,125 g i.a. de tiametoxan. Entre los tratamientos se incluyó un testigo sin aplicar. Las dosis intermedias y máximas de ambos productos controlaron eficazmente la plaga entre los meses de noviembre y marzo (120 días), mientras que en dos ensayos las dosis menores ejercieron control durante 25 y 45 días, y en un tercero no controlaron la plaga. A partir de los resultados obtenidos, se podría considerar más apropiado el uso de imidacloprid 35% SC en la dosis de 0,105 g i.a. por planta y tiametoxan 25% WG en la dosis de 0,075 g i.a. por planta, en un esquema de control del minador de la hoja de los cítricos en plantas de limonero en vivero.Citrus leafminer (CLM) Phyllocnistis citrella Stainton damages citrus leaves by producing galleries during larval stage. Nursery citrus trees and one and two-year-old citrus trees, which flush constantly during spring and summer, are the most affected by CLM. Plant growth is delayed and tree structure changes. To control this insect in citrus nurseries, several foliar sprays insecticides are needed every 10 to 15 days during the growing season. In this paper, CLM control in nursery lemon plants with systemic insecticides imidacloprid and thiametoxam, applied by "drench", is reported. Treatments were imidacloprid at 0.035, 0.105 and 0.175 g a.i. and thiametoxam at 0.025, 0.075 and 0.125 g a.i per plant in a five-liter container. An unsprayed control was included. CLM was effectively controlled from November to March (120 days approximately) with medium and high doses, and from 25 to 45 days with low doses of both insecticides. In one of the trials, imidacloprid and thiametoxam low doses did not control CLM. Considering the obtained results, it would be more appropriate to use imidacloprid 35% SC (0,105 g a. i. per plant) and thiametoxam 25% WG (0,075 g a. i. per plant) for citrus leafminer control in greenhouse plants.

The objective of this study was to evaluate the effects of maize (Zea mays) seed treatments for the control of Pratylenchus zeae under glasshouse conditions. Seeds of the maize hybrid DKB390 treated with thiametoxam, thiametoxam + abamectin and imidacloprid + thiodicarb were used as treatments. The treated maize seeds were sown in plastic cups containing soil inoculated with 200 nematodes (juveniles and females). Two of the four experiments that were done were evaluated at 60 and 90 days after sowing (DAS). The first experiment was evaluated 30, 60 and 90 DAS, and the fourth experiment only at 90 DAS. Fresh root mass and total nematodes extracted and counted from roots of each plant were used as the assessment criteria. All seed treatments tested showed a degree of efficacy in reducing the reproduction rates of P. zeae under glasshouse conditions. The imidacloprid + thiodicarb treatment showed consistent results in all replications of all four experiments, often being the one resulting in the lowest P. zeae density. The thiametoxam + abamectin treatment was also effective in reducing nematode numbers and differed significantly from the control treatments for all four experiments. Thiametoxam used on its own as a seed treatment proved to be as effective as the mixture with abamectin in two of the four experiments and does not provide consistent results in terms of reducing P. zeae population levels. [ABSTRACT FROM AUTHOR]

The aim of this research was to study the influence of two insecticides on spore germination and gametophyte differentiation in Asplenium scolopendrium and Athyrium filix-femina, non-target species of leptosporangiate pteridophytes. The insecticides used are from the neonicotinoids class and they contain thiametoxam 25% (T) and acetamiprid 20% (A). The experimental variants were T1-0.005%T, T2-0.01%T, T3-0.02%T, A1-0.005%A, A2-0.01%A, A3-0.02%A and the Control variant (C)-Knop solution. The spores were cultivated in 50 ml of experimental solutions. The culture vessels were kept in the growth room at controlled temperature, humidity and luminosity levels. The percentage of spore germination was determined after a week. Furthermore, microscopic observations were performed on gametophyte development after 3, 6 and 14 weeks, respectively from the initiation of cultures. Spore germination was influenced by both insecticides. In the case of thiametoxam, germination percentages decreased from 90% for the control variant to 81% in Athyrium filix-femina and 66% in Asplenium scolopendrium for the T3 variant. The acetamiprid reduces the germination percentages to 0% for the A3 variant in both species tested. The use of acetamiprid leads to delays in gametophyte differentiation. Of the two non-target species tested, Asplenium scolopendrium exhibited a more pronounced sensitivity to the effects of insecticides. [ABSTRACT FROM AUTHOR]

Pesticides are chemical compounds used in agriculture to destroy the pests and weeds but with great potential on environment contamination. An analytical method for screening and confirming the presence of 5 pesticides (acetamiprid, cymoxanil, mefenoxam, thiacloprid, thiametoxam) was developed. LC/MS/MS was proved to be a sensitive technique for these classes of compounds (insecticides and fungicides). Five calibration curves at six levels of concentration were obtained with good correlation coefficients (0.9960-0.9990). The method detection limit (MDL) ranges between 0.4-0.75 ng/ml and the method quantification limit (MQL) ranges between 1.2-2.25 ng/ml. Two methods: a liquid-liquid extraction and a solid phase extraction were tested. The selection criteria was the recovery degree which was prove to be more adequate for liquid-liquid extraction (71-102%) than for solid phase extraction (32-87%). [ABSTRACT FROM AUTHOR]

Efficiency of imidacloprid and thiametoxam on population growth parameters of Aphis gossypii Glover (Hemiptera: Aphididae) was assessed using three bioassay methods including; residual, starvation and FAO dip methods. Aphids were assayed under laboratory conditions at 23 ± 2°C, photoperiod of 16:8 (L:D) and 70% relative humidity. Aphids were transferred to sprayed leaves and Petri dishes in residual and starvation methods, respectively. There was no feeding for the aphids in starvation method. In FAO dip method, insects were dipped for 5 s in pesticide solutions and then transferred to fresh leaves. Results revealed that LC50 values calculated with the starvation and residual methods were respectively 15 and 11% more than FAO dip method (for imidacloprid) and 22 and 18% (for thiametoxam). The LC50 value in starvation method was 3% more than the residual method. Calculated LC50 in starvation and residual methods with imidacloprid respectively caused 160 and 34% increase in intrinsic rates of increase (r m) and net reproductive rate (R 0) in comparison with FAO dip method. Generation time (T) and doubling time (DT) were respectively 59 and 62% less than those in FAO dip method. In contrast, thiametoxam (LC50 concentration) in starvation and residual method lead to 9 and 67% increase in r m and R 0 parameters compared to FAO dip method. However T and DT were respectively 65 and 92% less than mentioned parameters in FAO dip method. There was not any significant difference between life table parameters calculated by residual and starvation bioassay methods. [ABSTRACT FROM PUBLISHER]

Sugar beet production remains unprotected after the ban on neonicotinoids, while pest pressure is increasing. Although the organic approach to agriculture is highly welcomed, the question remains whether it will be possible to grow sugar beet without pesticides. The aim of this study is to determine the efficacy of seed treatments with neonicotinoids on the main sugar beet pests, to determine the susceptibility of the pests under the specific climatic conditions and to discuss possible consequences of the ban of neonicotinoids on the future of sugar beet production in southeast Europe. The study was conducted in two different climatic regions in Croatia in two consecutive years. The tested variants were: seed coated with imidacloprid, seed coated with a combination of thiamethoxam and teflutrin and untreated control. Our results showed that seed coatings with imidacloprid and thiamethoxam provided satisfactory protection against wireworms, flea beetles and sugar beet weevils at low population pressure. These pests are regular pests of sugar beet in southern and eastern Europe and therefore need to be controlled. Caterpillars and aphids were present in low populations, so the efficacy of the insecticides tested cannot be determined with certainty. A further research program is needed to find alternative solutions and develop easily implementable strategies for all sugar beet pests. We would propose an authorization of neonicotinoids for seed treatment of sugar beet in the regions with high infestation pressure of the main sugar beet pests. [ABSTRACT FROM AUTHOR]