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The toxicity of neonicotinoids and many of their replacement insecticides to nontarget soil invertebrates such as earthworms has previously been established. However, the long‐term effects of these substances on these organisms are largely unknown. In the field of soil ecotoxicology, lumbricid earthworms such as Eisenia andrei are used extensively due to the availability of standardized test methods and their adaptability to laboratory culture and testing. Multigenerational studies have gained popularity and attention in recent years, with a shift toward the use of long‐term assays and lower concentrations of test chemicals. The use of exposure concentrations that include those measured in a monitoring program carried out by the Government of Ontario presents a realistic exposure scenario that may not show significant effects in contemporary, shorter term studies. We used current standardized test methods as a basis for the development of multigenerational studies on E. andrei. The effects of exposure to a single application of the insecticides thiamethoxam and cyantraniliprole on the survival and reproduction of E. andrei were observed over three (thiamethoxam) or two (cyantraniliprole) generations using consecutive reproduction tests. No significant impacts on adult survival were reported in any generation for either insecticide, whereas reproduction decreased between the first and second generations in the thiamethoxam test, with median effective concentration (EC50) values of 0.022 mg/kg dry weight reported for the first generation compared with 0.002 mg/kg dry weight in the second generation. For cyantraniliprole, an EC50 of 0.064 was determined for the first generation compared with 0.016 mg/kg dry weight in the second generation. A third generation was completed for the thiamethoxam test, and a significant decrease in reproduction was observed in all treatments and controls compared with previous generations. No significant difference between thiamethoxam treatments and the control treatment was reported for the third generation. Collectively, these data indicate that exposure of oligochaetes to these two insecticides at concentrations representative of field conditions may result in long‐term stresses. Environ Toxicol Chem 2024;43:2058–2070. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Nesidiocoris tenuis (Reuter) (Heteroptera Miridae) is a key biological control agent of the tomato leaf miner Tuta absoluta (Meyrick). However, in cases of prey scarcity, this predator switches into a phytophagous pest causing ring injuries in stems of tomato plants. The aim of this study was to assess the side effects of dry residues and explore the presence of target site resistance mutations of 10 insecticides, two bioinsecticides, an acaricide and a fungicide widely applied in IPM, on adults of N. tenuis collected from two different regions of Crete; the Western and the Eastern side of the island during two successive years. Lethal toxicity trials were performed on sprayed tomato stems and toxicity of adults of N. tenuis was recorded 2 h, 7 and 14 days after exposure. At both populations, chlorpyrifos, acetamiprid and thiamethoxam were moderately harmful at the application day and slightly harmful 7 days after the application. Only chlorpyrifos maintained its toxicity for more than 7 days. All the rest tested pesticides (emamectin benzoate, abamectin, chlorantraniliprole+abamectin, chlorantraniliprole, deltamethrin, tebufenpyrad, spinosad, Bacillus thuringiensis var kurstaki, metaflumizone and myclobutanil) were classified as harmless. Additionally, analysis of insecticide target site sequences indicated the absence of resistance mutations in both populations. Overall, our findings illustrate the impact of 15 pesticides and their residual toxicity on the mortality rates of N. tenuis adults. [ABSTRACT FROM AUTHOR]

Honey bees provide key ecosystem services i.e., pollination but are functioning under various biotic and abiotic stresses. Among various stresses, thiamethoxam has been criticized worldwide. Since no scientific study on its sub-lethal effects on honey bees has been conducted in India, the present work was carried out at the Department of Entomology, Punjab Agricultural University, Ludhiana for two seasons during 2017-19. The median lethal dietary dose (LDD50) of thiamethoxam upon chronically feeding the sub-lethal doses for 10 days for a group of adult Apis mellifera bees (age 10 days) was 0.421 ng bee−1 day−1. At this level, the reduction in the area of an acinus of the hypopharyngeal gland was significant i.e., 36.62 and 37.92 percent over control during spring and winter seasons, respectively. The adverse impact of thiamethoxam on hypopharyngeal glands will be limiting the development and productivity of the honey bee colonies. [ABSTRACT FROM AUTHOR]

Temperature can interact with chemical pesticides and modulate their toxicity. Sublethal exposure to pesticides is known to trigger hormetic responses in pests. However, the simultaneous effects of temperature and sublethal exposure to single or mixture-based insecticides on the insects' stimulatory responses are not frequently considered in toxicological studies. Here we investigated the combined effects of temperature on the lethal and sublethal responses of the green peach aphid Myzus persicae after exposure to commercial formulations of a neonicotinoid (thiamethoxam) and a pyrethroid (lambda-cyhalothrin) and their mixture. Firstly, the concentration-response curves of the insecticides were determined under four temperatures (15 °C, 20 °C, 25 °C, and 28 °C) by the leaf dipping method. Subsequently, the sublethal concentrations C0, CL1, CL5, CL10, CL15, CL20, and CL30 were selected to assess sublethal effects on aphids' longevity and reproduction under the same temperatures. The results showed that the mixture of thiamethoxam + lambda-cyhalothrin caused greater toxicity to aphids compared to the formulations with each active ingredient alone and that the toxicity was higher at elevated temperatures. Furthermore, the exposure to low concentrations of the mixture (thiamethoxam + lambda-cyhalothrin) and the separated insecticides induced stimulatory responses in the longevity and fecundity of exposed aphid females, but the occurrence of such hormetic responses depended on the insecticide type, its sublethal concentration, and the temperature as well as their interactions. [ABSTRACT FROM AUTHOR]

Simple Summary: Several differentially expressed genes encoding cytochrome P450 monooxygenases (P450s) and UDP-glycosyltransferases (UGTs), namely, CYP9Z140, CYP9AY1, and UGT321AP1, were screened and verified between thiamethoxam-susceptible and resistant populations of Leptinotarsa decemlineata (Say). The expression of the three genes was significantly enhanced after exposure to thiamethoxam. RNA interference of three genes increased mortality of test adults following thiamethoxam treatment. The findings reveal that the three genes have roles in the thiamethoxam resistance of L. decemlineata. Cytochrome P450 monooxygenases (P450s) and UDP-glycosyltransferases (UGTs) are involved in the evolution of insecticide resistance. Leptinotarsa decemlineata (Say), the Colorado potato beetle (CPB), is a notorious insect that has developed resistance to various insecticides including neonicotinoids. This study investigated whether the differentially expressed P450 genes CYP9Z140 and CYP9AY1 and UGT gene UGT321AP1, found in our transcriptome results, conferred resistance to thiamethoxam in L. decemlineata. Resistance monitoring showed that the sampled field populations of L. decemlineata adults collected from Urumqi City and Qapqal, Jimsar, and Mulei Counties of Xinjiang in 2021–2023 developed low levels of resistance to thiamethoxam with resistance ratios ranging from 6.66- to 9.52-fold. Expression analyses indicated that CYP9Z140, CYP9AY1, and UGT321AP1 were significantly upregulated in thiamethoxam-resistant populations compared with susceptible populations. The expression of all three genes also increased significantly after thiamethoxam treatment compared with the control. Spatiotemporal expression patterns showed that the highest expression of CYP9Z140 and CYP9AY1 occurred in pupae and the midgut, whereas UGT321AP1 was highly expressed in adults and Malpighian tubules. Knocking down all three genes individually or simultaneously using RNA interference increased the sensitivity of adult L. decemlineata to thiamethoxam. These results suggest that overexpression of CYP9Z140, CYP9AY1, and UGT321AP1 contributes to the development of thiamethoxam resistance in L. decemlineata and provides a scientific basis for improving new resistance management of CPB. [ABSTRACT FROM AUTHOR]

Neonicotinoids are insecticides used worldwide in phytosanitary and biocidal products and veterinary pharmaceuticals. Recently, some restrictions and bans have been imposed due to their adverse effects on nontarget invertebrates, including pollinators. Although they may have direct and indirect effects on wild vertebrates, few studies have assessed exposure to these compounds in wild birds, so our knowledge remains limited. In the present pilot study we have assessed the prevalence of seven neonicotinoid insecticides and some of their metabolites in whole blood samples from 19 European roller (Coracias garrulus) nestlings and five adult common kestrels (Falco tinnunculus) in an area treated with neonicotinoids to control the palm weevil (Rynchophorus ferrugineus) in southeastern Spain. One European roller nestling born in a palm tree was positive for thiamethoxam, with a concentration of 2.26 ng mL−1, but no residues of neonicotinoids or their metabolites were found in adult common kestrels. Future studies are needed to elucidate potential exposure to neonicotinoids at different times of the year. To our knowledge, this is the first report of the presence of thiamethoxam residues in whole blood of a wild bird species after its ban in Spain. Environ Toxicol Chem 2024;43:1836–1843. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Lycorma delicatula White (Hemiptera: Fulgoridae), spotted lanternfly, is a univoltine, phloem-feeding, polyphagous and invasive insect in the United States. Although a primary host for this species is Ailanthus altissima (Mill.) Swingle, tree of heaven, L. delicatula also feeds on many other plant species, including cultivated grapevines. As this species continues to spread, it is important to develop effective management tools. Here, we evaluated the residual efficacy of 4 insecticides commonly used in tree fruit management programs: dinotefuran, bifenthrin, carbaryl, and thiamethoxam. First, all mobile life stages (early instars, late instars, and adults) of L. delicatula were exposed for 1 h to dry insecticide residues (18 h old) applied to glass or A. altissima bark surfaces. While some mortality was detected immediately following the 1 h exposure period, 100% mortality occurred within 24 h for all materials and life stages exposed on both glass and bark surfaces. To evaluate longer residual activity of these materials, groups of adult L. delicatula were introduced into cages containing A. altissima trees treated with the same individual insecticides and exposed 6 h to residues that were 18 h or 7 days old. Paired, untreated A. altissima served as controls. In these bioassays, 48 h mortality for 18 h old residue reached 95% for thiamethoxam and 100% for bifenthrin and dinotefuran. Seven-day-old bifenthrin and dinotefuran residues again yielded 100% mortality, while thiamethoxam resulted in 58% mortality, and carbaryl yielded only 13.3% and was not significantly different from the control. These results clearly document the efficacy of specific insecticide applications as management tools against L. delicatula. [ABSTRACT FROM AUTHOR]

In eusocial insects, worker longevity is essential to ensure colony survival in brood-free periods. Trade-offs between longevity and other traits may render long-living workers in brood-free periods more susceptible to pesticides compared to short-lived ones. Further, colony environment (e.g., adequate nutrition) may enable workers to better cope with pesticides, yet data comparing long vs. short-living workers and the role of the colony environment for pesticide tolerance are scarce. Here, we show that long-living honey bee workers, Apis mellifera, are less susceptible to the neonicotinoid thiamethoxam than short-lived workers, and that susceptibility was further reduced when workers were acclimatized under colony compared to laboratory conditions. Following an OECD protocol, freshly-emerged workers were exposed to thiamethoxam in summer and winter and either acclimatized within their colony or in the laboratory. Mortality and sucrose consumption were measured daily and revealed that winter workers were significantly less susceptible than summer workers, despite being exposed to higher thiamethoxam dosages due to increased food consumption. Disparencies in fat body activity, which is key for detoxification, may explain why winter bees were less susceptible. Furthermore, colony acclimatization significantly reduced susceptibility towards thiamethoxam in winter workers likely due to enhanced protein nutrition. Brood absence and colony environment seem to govern workers' ability to cope with pesticides, which should be considered in risk assessments. Since honey bee colony losses occur mostly over winter, long-term studies assessing the effects of pesticide exposure on winter bees are required to better understand the underlying mechanisms. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Neonicotinoid insecticide seed treatments are commonly used in rice (Oryza sativa) production to control rice water weevil (Lisorhoptrus oryzophilus). With the use of neonicotinoid seed treatments, there is potential that honey bees (Apis mellifera) could be exposed to neonicotinoids through translocation to the pollen. Studies were conducted in 2015 and 2016 to determine the level of neonicotinoids present in flag leaves, pollen, and grain of rice. Thiamethoxam was applied as a seed treatment and foliar prior to flooding. Clothianidin was applied as a seed treatment and as a foliar at a preflood and postflood timing. Subsamples of flag leaves, pollen, and grain were analyzed for positive neonicotinoid detections and abundance. Thiamethoxam was detected in 8.9% of samples and clothianidin was detected in 1.4% of samples. For both thiamethoxam and clothianidin, more positive samples were observed in flag leaf samples than in pollen or grain. An average of 4.30 ng/g of thiamethoxam was detected in flag leaves from seed-applied thiamethoxam. An average of 1.25 ng/g of clothianidin was found in flag leaves from a preflood application of clothianidin. A survey of honey bees present in rice fields was conducted in Mississippi and Arkansas to determine the abundance of honey bees present in rice fields based on the time of day. Honey bee densities were low in rice, with less than 5% and 3% positive detections observed in Mississippi and Arkansas, respectively. More positive detections and higher densities of honey bees were observed for mid-day sampling than for morning or evening sampling. [ABSTRACT FROM AUTHOR]

Copyright of Acta Edulis Fungi is the property of Acta Edulis Fungi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As an important pest on winter wheat, Rhopalosiphum padi (L.) causes damage to the wheat yield by sucking plant nutrients, transmitting plant viruses and producing mildew. R. padi has been reported to develop resistance to pyrethroids and neonicotinoids. To explore potential alternative approaches for R. padi control, the activity of 10 botanical insecticides was evaluated. Results suggested that the toxicity of rotenone and pyrethrins to R. padi were the highest and near to the commonly used chemical insecticides. When exposed to the low-lethal concentrations (LC10, LC30) of rotenone or pyrethrins for 24 h, the lifespan and fecundity of adults in F0 generation decreased significantly compared to control. The negative effect could also be observed in the F1 generation, including the decreased average offspring, longevity of adult, and prolonged nymph period. The population parameters in F1 generation of R. padi were also inhibited by exposing to the low-lethal concentrations of rotenone or pyrethrins, including the decreased net reproductive rate, intrinsic rate of natural increase, finite rate of population increase, and gross reproduction rate. Co-toxocity factor results showed that mixtures of rotenone and thiamethoxam, pyrethrins and thiamethoxam showed synergistic effect. Our work suggested that rotenone and pyrethrins showed negative effect on the population growth under low-lethal concentrations. They are suitable for R. padi control as foliar spraying without causing population resurgence. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study is to explore the novel use of natural polymers like Humic acid, Lignin, and Lignite based hydrogels for the formulation of pesticides and fertilizers that would reduce the residues in soil and run‐off water that pose a threat to human health and the environment. We synthesized hydrogels by grafting Humic acid, lignin, and lignite onto acrylic acid with N′N‐methylene bisacrylamide (MBA) for the ex‐situ encapsulation of thiamethoxam, a common pesticide. Various characterization techniques including Fourier‐transform infrared spectroscopy, Carbon‐13 Solid‐state Cross‐Polarization Magic Angle Spinning Nuclear Magnetic Resonance, X‐ray diffraction, Thermogravimetric Analysis, and Rheology were employed. The release kinetics of thiamethoxam in water from the developed formulations were analyzed using the Korsmeyer‐ Peppas model and the Weibull model. Humic acid and lignin‐based hydrogels exhibited a long‐sustained release for 49 hours, followed by lignite‐based hydrogels (38 hours). According to ANOVA results, the change of biopolymer proved to be an effective factor in reducing the water evaporation rate, which decreased from 99 % to 72.85 % in the soil amended with synthesized hydrogels. In conclusion, the novel formulations of humic acid, lignin, and lignite exhibit potential as slow‐release vehicles for pesticides and fertilizers. This study provides valuable insights for the research community, addressing the need to develop effective strategies for mitigating pesticide residues in soil and water bodies. [ABSTRACT FROM AUTHOR]

Seed coating with pesticides is used extensively for the protection of both seeds and plants against pests. In this study, the uptake and transport of seed-coating pesticides (insecticides), including cyantraniliprole (CYN) and thiamethoxam (THX), were investigated. The translocation of these pesticides from the soil to the plant and their accumulation in different plant parts were also calculated. After sowing the seeds with seed coating pesticides, soil and plant samples were taken across the study area. These samples were extracted and analyzed in liquid chromatography with tandem mass spectrometry (LC–MS/MS). CYN and THX were used in maize plants for the first time to observe soil degradation kinetics, and CYN showed a higher half-life than THX in soil. Both pesticides have been taken up by the corn maize plant and transferred and accumulated to the upper parts of the plant. Although the THX concentration was between 2.240 and 0.003 mg/kg in the root, between 3.360 and 0.085 mg/kg in the stem, it was between 0.277 and 3.980 mg/kg in the leaf, whereas CYN was detected at higher concentrations. The concentration of CYN was 1.472 mg/ kg and 0.079 mg/kg in the roots and stems of the maize plant, respectively. However, the bioconcentration factor (BCF) indicates the soil-to-plant accumulation of CYN from 28 to 34.6 and that of 12.5 to 4567.1 for THX on different sampling days. The translocation factor (TFstem) represents the ratio of pesticides absorbed from the stem and transported to the roots. For CYN, TFstem ranges from 3.6 to 20.5, while for THX, it varies between 1.5 and 26.8, indicating a higher translocation rate for THX. The ratio of leaf to root concentration are 3.6 to 20.5 for CYN and 1.8 to 87.7 for THX, demonstrating effective translocation for both pesticides. The TF values for both pesticides are above 1, signifying successful root-to-stem-to-leaf movement. Notably, THX exhibits a notably higher transport rate compared to CYN. [ABSTRACT FROM AUTHOR]

The study investigated the insecticide tolerance and dissipation potential of five Trichoderma isolates, namely T. asperellum (4 isolates) and T. harzianum (single isolate), to thiamethoxam and chlorantraniliprole in treated liquid medium and tomato fruit. The isolates were identified using ITS gene amplification and sequencing regions. In vitro tolerance was assessed using a poisoned medium technique, with mycelial placed onto Potato Dextrose Agar (PDA.) media supplemented with commercial insecticides at recommended doses. Dissipation potential was determined using the isolates after independently inoculating them into PDB liquid media with Actara and Voliam Flexi. The results showed that the inhibitory effect of thiamethoxam and chlorantraniliprole was almost zero, and the five isolates were competent to reach 9 cm growth like the control after 96 h of incubation at 25°C ± 2°C. Mycelial fresh weights of T. harzianum EGY-T4 and T. asperellum EGY-T5 were significantly equal to their respective control without insecticide. T. asperellum EGY-T1 had the highest dissipation rate of 36% and 30% for thiamethoxam in Actara and Voliam Flexi when applied at the higher dose of 100 mg L-1. The dissipation rate of thiamethoxam was recorded at 92.2% when applied in combination with T. asperellum EGY-T1, reducing the PHI from 7 to 4 days. Chlorantraniliprole was dissipated to the extent of 51.3 and 99.5% when applied in combination with T. asperellum EGY-T1 and T. harzianum EGY-T4, respectively, with residues reaching up to 0.12 and 0.21 mg kg-1 after one day. [ABSTRACT FROM AUTHOR]

Repeated pesticide residue detection in chili peppers in the Republic of Korea has become a serious health concern. Thus, monitoring domestically grown and imported chili peppers for pesticide residues is of great significance. Here, we investigated pesticide residues detected in imported and domestically grown chili peppers using global pesticide residue monitoring data. Our analysis involved organizing inspection and detection data from different sources. Global pesticide residue monitoring data for chili peppers revealed 139 pesticide types, 43,532 inspections, and 3966 detections (detection rate, 9.11%). Peppers from Mexico were sampled the most (39,927 inspections) and showed the highest number of detected cases (2998 cases). Globally, the top 10 most frequently detected pesticides were clothianidin, imidacloprid, thiamethoxam, chlorpyrifos, thiacloprid, metalaxyl, myclobutanil, azoxystrobin, carbendazim, and cyhalothrin, with detection rates in the range of 10.52–28.66%. Furthermore, domestic chili pepper pesticide residue monitoring revealed 73 pesticide types, 3535 inspections, and 332 detected cases (detection rate, 9.39%), and the top 10 most frequently detected pesticides were chlorfenapyr, tebuconazole, flonicamid, dinotefuran, boscalid, pyraclostrobin, fluxametamide, thiamethoxam, pyridaben, and azoxystrobin, with detection rates in the range of 13.89–32.58%. These findings may serve as fundamental data for safety management related to chili pepper pesticide residues in the Republic of Korea. [ABSTRACT FROM AUTHOR]

The stink bug, Riptortus pedestris (Fabricius) (Hemiptera: Alydidae), is a highly destructive pest that significantly damages legume crops in East and South Asia. Neonicotinoid insecticides containing thiamethoxam are widely used to control R. pedestris in soybean fields. However, the current knowledge on the impact of different thiamethoxam concentrations on R. pedestris growth and reproduction is lacking and insufficient. The present study investigated the effects of thiamethoxam on the biological traits of R. pedestris after treatment with LC10 (19.8 mg/L), LC20 (31.6 mg/L), LC30 (44.2 mg/L), LC40 (58.9 mg/L), and LC50 (77.0 mg/L) concentrations. These five thiamethoxam concentrations (LC10~LC50) reduced adult longevity and fecundity in the F1 generation females. Thiamethoxam treatment also significantly decreased the population trend index, intrinsic rate of increase, net reproductive rate, gross reproductive rate, and finite rate of increase and increased the mean generation time. These results show that thiamethoxam hinders and suppresses the development and growth of the F1 population of R. pedestris. Thiamethoxam is recommended for spray control during peak adult emergence, as it not only has a controlling effect on the parental generation but also a negative impact on the F1 generations. [ABSTRACT FROM AUTHOR]

Advanced oxidative processes, such as Photo-Fenton, transform organic contaminants due to the attack by radicals. In this context, the lethal and sub-lethal effects of the Cruiser® 350FS (CRZ) with the active ingredient thiamethoxam (TMX) were investigated using the planarian Girardia tigrina. Degradation of thiamethoxam by the Fenton process was also assessed by using theoretical studies and the efficiency of Solar-Fenton versus Fenton. The 48 h LC50 value of CRZ for planarians was 478.6 mg L−1. The regeneration of planarians was significantly affected for concentrations ≥ 17 mg·L−1 of TMX (24 h). The Solar-Fenton showed a high degradation percentage reaching ~70%. The theoretical model showed the atoms of the TMX molecule that will suffer attacks from the formed radicals. Current results open new perspectives concerning the treatment of TMX in the aquatic environment because the 70% degradation seems to be sufficient to reach concentrations that do not induce sub-lethal effects in planarians. Further studies should determine if the by-products generated might be toxic for planaria or other organisms. [ABSTRACT FROM AUTHOR]

Field studies were carried out to assess the incidence and management of whitefly, Bemisia tabaci (Gennadius) on nine promising potato varieties under sprayed condition and unsprayed condition during 2022-23 and 2023-24 at Chaudhary Charan Singh University, Meerut, U.P., India. The maximum incidence of whitefly (15.32/10 plants) was recorded in Kufri Lima followed by Kufri Lohit (14.57/10 plants), when crop remained unsprayed condition. In protected potato varieties viz., Kufri Kiran, Kufri Chipsona-1, Kufri Anand, Kufri Chipsona-3, Kufri Lohit, Kufri Khyati, Kufri Mohan, Kufri Bahar and Kufri Lima, the population of whitefly was low as compared to unsprayed condition. Potato varieties viz., Kufri Khyati, Kufri Anand and Kufri Mohan recorded the highest mean tuber yield of 43.51, 42.38, and 41.04 t/ha, respectively under sprayed condition. Similarly these varieties recorded maximum yield even under unsprayed condition. Thus, it is concluded from the present study that for effective management of whitefly, potato crop should be well protected by seed treatment with Imidacloprid followed by first spray of pymetrozine 50WG @ 0.06% (6 g/10 l), second spray of thiamethoxam 25 WG @ 0.05% (5 ml/10 l) and third spray of imidacloprid 17.8 SL @ 0.03% (3 ml/10 l) as and when there will be any buildup of whitefly on potato, especially for seed crop to get maximum potential yield. [ABSTRACT FROM AUTHOR]

Efficacy of thiamethoxam 25 WG, an insecticide of neonicotinoid class @ 50, 75, 100 and 125 g/ha was evaluated against aphids in potato crop along with oxydemeton methyl 25 EC @ 750 ml/ha as a standard check at Entomological Research Farm, Ludhiana during 2018 and at three locations (Ludhiana, Jalandhar and Amritsar) through multi-location research trial during 2019. An untreated control was also kept for comparison. Thiamethoxam 25 WG @ 100 g/ha proved significantly better than its lower dosages of 50 and 75 g/ha in controlling aphids in potato and the untreated control. Thiamethoxam 25 WG @ 125 g/ha recorded minimum (0.74 mean numbers) of aphids per 3 leaves (pooled mean of 3 locations) after 7-days of spraying the insecticide. Thiamethoxam 25 WG @ 100 and 125 g/ha resulted in significantly higher yield of 276.84 and 277.28 q/ha, respectively in pooled analysis and was significantly better than all other treatments. The net returns over control in thiamethoxam @ 100 g/ha were also better than oxydemeton methyl 25 EC. Hence, based on the above results, it can be concluded that the new molecule i.e., thiamethoxam @ 100 g/ha is effective against aphids infesting potato and will help in better management of this insect pest. It will also enhance the choice of farmers to select the chemicals from different groups. [ABSTRACT FROM AUTHOR]

Winter wheat (Triticum aestivum L.) yields are gradually increasing in Russian plains, though a limited yield exists, which could point back to insect pest incursion in wheat fields. However, in the past up to the present, yield losses due to insect pest invasion were approximately 20% annually. The latest study aims to determine the effectiveness of the insecticide Thiamethoxam (350 g/l) used in controlling insect pests through wheat seed treatment. The experiments laid out in 2019 and 2020 in the foothill zone of Abinsky, Astrakhan region, Russian Federation. The randomized complete block design (RCBD) used with four replications and a plot size of 100 m² . The treatment included one winter wheat variety and four treatments: T1 = Kaytoks, KS @ 0.5 l/t, T2 = Kaytoks, KS @ 1.0 l/t, T3 = Cruiser, KS @ 1.0 l/t, and T4 = the control (untreated). Based on the crop season evaluation, a significant increase resulted in the pest population (4.74 to 26.57 adults/m² ) in the control plots. The plots amended with insecticide Thiamethoxam (350 g/l) at the rate of 0.5 l/t showed lesser pest population (0.25 to 1.25 adults/m² ), and plots with 1.0 l/t ranged from 0 to 0.5 adults/m² . Results also revealed that insecticides of the manufacturers, i.e., Kaytoks, KS, and Cruiser, KS, proved effective in pest control, ranging from 80 to 100%. The wheat seeds treated with Kaytoks, KS (0.5 l/t) and (1.0 l/t) increased their yield compared with control by 9.3 to 14.8% (2019) and 15.6 to 17.3% (2020). Thus, to achieve insect pest control and yield increase in wheat varieties, seed treatment using Thiamethoxam (Kaytoks, KS) at an application rate of 1.0 l/t can be a vital crop protection tool for cereal crops and an eco-friendly method. [ABSTRACT FROM AUTHOR]

Most pesticide research has focussed on risk to managed honeybees, but other managed and wild bees are also exposed to pesticides. Critically, we know little about the magnitude and sources of risk to honeybees compared with other bees during crop pollination.To compare pesticide exposure and risk across wild and managed bees, we sampled the main bee groups present during bloom in 20 apple orchards, including managed honeybees (Apis mellifera), managed bumblebee workers (Bombus impatiens), wild mining bees (Andrena spp. and Andrena [Melandrena] spp.), bumblebee foundress queens (Bombus impatiens) and eastern carpenter bees (Xylocopa virginica). We screened all bees for 92 pesticides and computed a Risk Quotient using available toxicity data (honeybee LD50s), adjusting for differences in toxicity known to scale with body mass. To gain insight into exposure origin, we compared residues in bees to those in focal orchard apple and dandelion flowers.Nearly all bee samples contained pesticides (95%), with the average contamination level ranging from 7.1 ± 2.8 parts per billion (ppb) in B. impatiens workers to 388.4 ± 146.2 ppb in Andrena. Exposure profiles were similar for all bees except A. mellifera, whose unique exposure profile included high levels of the neonicotinoid insecticide thiamethoxam.All bee groups except wild B. impatiens queens had at least one sample exceeding a US Environmental Protection Agency or European Food Safety Authority exposure level of concern. Apis mellifera experienced significantly greater risk than other bee groups, with 63% and 81% of samples exceeding an acute or chronic exposure level of concern, respectively. Risk to honeybees was driven primarily by high thiamethoxam levels not found in focal orchard flowers and likely originating outside the orchard.Synthesis and applications: We find that pesticide exposure and risk differ between honeybees and other managed and wild bees during apple pollination. Furthermore, pesticide exposure is a landscape‐scale phenomenon and therefore measures to reduce exposure must consider the surroundings beyond focal farms. Limiting orchard sprays, while reducing on‐farm exposures, will not protect far‐foraging bees from off‐farm exposures such as thiamethoxam, which we hypothesize is coming from nearby seed‐treated corn fields planted during apple bloom. [ABSTRACT FROM AUTHOR]

Thiamethoxam, a systemic neonicotinoid insecticide, is widely accepted for use against various chewing and sucking insect pests. In this particular study, the authors examined the dissipation kinetics and metabolism of thiamethoxam in wheat using quick, easy, cheap, effective, rugged and safe (QuEChERS) methodology combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) over two years during the same cropping season. Residues of thiamethoxam and its metabolites in wheat plants were investigated following foliar spray of thiamethoxam at recommended dose (12.5 g a.i. ha−1) and four times the recommended dose (50.0 g a.i. ha−1) at earhead formation stage. Total residues of thiamethoxam and its metabolites in leaves at 0 day (2 h after spray) ranged from 3.69 to 14.36 mg kg−1 for the two doses over the two years. Clothianidin was the only metabolite detected in leaves at 0 day (2 h after spray); however at 7 days after spray nitroguanidine, N-desmethyl-thiamethoxam and 1-methyl-3-nitroguanidine were also detected. Total residues of thiamethoxam and its metabolites in soil at 0 day (2 h after spray) ranged from 0.23 to 0.84 mg kg−1. Thiamethoxam residue in leaves and soil followed first order kinetics with half-life ranging from 9.04 to 15.50 days for the two doses over the two study years. Residues of thiamethoxam and its metabolites in leaves, straw and grain at harvest time for both the doses were below their limit of quantification (0.01 mg kg−1). This information could be helpful for evaluating both regulatory and food safety decisions regarding use of neonicotinoids. [ABSTRACT FROM AUTHOR]

Simple Summary: Bemisia tabaci (Gennadius) is a worldwide agricultural pest and is one of the most harmful invasive insect pests in the world. The overuse of insecticides has caused B. tabaci to develop high resistance against multiple insecticidal chemicals. It is well recognized that over-expression of cytochrome P450s involved in insecticide detoxification is one common and major mechanism of resistance to various classes of insecticides in insects. In addition to gene duplication and amplification, up-regulation of P450s at the transcriptional level is a common and important mechanism for P450-mediated insecticide resistance. Here, two new CYP450 genes from B. tabaci MEAM1 were cloned, and their expression patterns were studied in response to two different insecticides, high temperature, and their combined effects. The results showed that the insecticide tolerance could be reduced by high temperatures; under combined stress, the mortality of B. tabaci MEAM1 increased. This study is an important addition to the research on insecticide tolerance in B. tabaci and may help to reduce the overreliance on insecticides for B. tabaci control. Bemisia tabaci (Gennadius) is one of the most important invasive species in China, with strong insecticide resistance and thermotolerance. In this study, we investigated the effects of elevated temperature on the tolerance of B. tabaci MEMA1 to abamectin (AB) and thianethixam (TH) insecticides. We firstly cloned two new CYP450 genes from B. tabaci MEAM1, including one CYP6 family gene (BtCYP6k1) and one CYP305 family gene (BtCYP305a1). The expression patterns of the two BtCYP450 genes were compared in response to high-temperature stress and insecticide exposure, and RNAi was then used to demonstrate the role that these two genes play in insecticide tolerance. The results showed that expression of the two BtCYP450 genes could be induced by exposure to elevated temperature or insecticide, but this gene expression could be inhibited to a certain extent when insects were exposed to the combined effects of high temperature and insecticide treatment. For AB treatment, the expression of the two BtCYP450 genes reached the lowest level when insects were exposed to a temperature of 41 °C and treated with AB (combined effects of temperature and insecticide). In contrast, TH treatment showed a general decrease in the expression of the two BtCYP450 genes with exposure to elevated temperatures. These findings suggest that insecticide tolerance in B. tabaci MEAM1 could be mediated by high temperatures. This study provides a prospective method for the more effective application of insecticides for the control of B. tabaci in the field. [ABSTRACT FROM AUTHOR]

Thiamethoxam and beta-cyfluthrin are commonly used insecticides for aphid control in greenhouse celery. It is of great significance to reveal their dissipation and accumulation characteristics for evaluating their dietary intake risks and optimizing application methods. Based on this, gas chromatography-tandem triple quadrupole mass spectrometry was used in the multi-reaction monitoring mode of mass spectrometry, The dynamics of residue digestion of two insecticides under three repeated spraying methods (combination I: thiamethoxam + beta-cyfluthrin, alternating II: thiamethoxam -betacyfluthrin - thiamethoxam, alternating III: beta-cyfluthrin - thiamethoxam - beta-cyfluthrin) and assessed the risk of chronic dietary intake. The results showed under the three continuous spraying methods, the original deposition amount was the highest after the second spraying (22 d after planting) and the lowest after the first spraying; and the celery leaf area index may be an important factor causing this phenomenon. According to the first-order kinetic equations, the digestion half-life of thiamethoxam and beta-cyfluthrin were 2.95-3.63 d and 2.33-3.11 d, respectively. Comparative analysis of residues after the safety interval of 7 d after three repeated spraying, residue of thiamethoxam and beta-cyfluthrin in combination I was higher than maximum residue limit (MRL) except for the first spraying(thiamethoxam:1mg/kg; beta-cyfluthrin:0.5 mg/kg); However, the residue of beta-cyfluthrin in alternating III exceeds the MRL after the last spraying. Since thiamethoxam could be metabolized to clothianidin, dynamic residue of clothianidin was determined. The highest concentration was obtained at 3-5 d after spraying. However, the residue of clothianidin was lower than MRL(0.04 mg/kg) after the pre-harvest interval (PHI); The results of risk assessment of dietary intake showed that in this standardized residue test in Shaoxing, Zhejiang Province, thiamethoxam and beta-cyfluthrin were combined and applied alternatly for three times. After the PHI of 7 d, the contribution rate of thiamethoxam and beta-cyfluthrin residues in celery samples collected to risk quotient (0.11%~3.76%) was lower than 100%, and the long-term dietary intake risk was at an acceptable level. The results showed that compared with combined application, pesticide residues could be reduced to some extent by alternate spraying, and the alternate spraying of thiamethoxam - bata-cyfluthrin - thiamethoxam showed the lowest residue level and contribution rate of dietary intake risk, which was the relatively best application strategy. [ABSTRACT FROM AUTHOR]

Risk assessment for bees is mainly based on data for honey bees; however, risk assessment is intended to protect all bee species. This raises the question of whether data for honey bees are a good proxy for other bee species. This issue is not new and has resulted in several publications in which the sensitivity of bee species is compared based on the values of the 48‐h median lethal dose (LD50) from acute test results. When this approach is used, observed differences in sensitivity may result both from differences in kinetics and from inherent differences in species sensitivity. In addition, the physiology of the bee, like its overall size, the size of the honey stomach (for acute oral tests), and the physical appearance (for acute contact tests) also influences the sensitivity of the bee. The recently introduced Toxicokinetic–Toxicodynamic (TKTD) model that was developed for the interpretation of honey bee tests (Bee General Uniform Threshold Model for Survival [BeeGUTS]) could integrate the results of acute oral tests, acute contact tests, and chronic tests within one consistent framework. We show that the BeeGUTS model can be calibrated and validated for other bee species and also that the honey bee is among the more sensitive bee species. In addition, we found that differences in sensitivity between species are smaller than previously published comparisons based on 48‐h LD50 values. The time‐dependency of the LD50 and the specifics of the bee physiology are the main causes of the wider variation found in the published literature. Environ Toxicol Chem 2024;43:1431–1441. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Honey bees come under stress if thiamethoxam (a neonicotinoid insecticide) is used on their forage crops. The lethal and sub-lethal effects of this insecticide have largely been documented on foraging bees in comparison to the non-foraging stages especially the immature stages. Hence, the present study, to know the effect of thiamethoxam (25 and 50 g a.i. ha−1) on the brood of Apis mellifera colonies in mustard was conducted. Brood index, compensation index, and brood termination rate were calculated for the brood area (2 sq. inch) selected at two time intervals i.e. at the time of spray (D0) and seven days after that (D7). Brood index for the brood selected at D7 of thiamethoxam applied at 25 g a.i. ha−1 was statistically at par with the untreated control i.e. its value at 21 days (1.00 ± 0.00-4.48 ± 0.04) was statistically at par with the untreated control (1.00 ± 0.00-4.66 ± 0.01). However, in other treatments viz. brood selected at D0 in thiamethoxam applied at 25 g a.i. ha−1 and at D0 and D7 in thiamethoxam applied at 50 g a.i. ha−1, significant brood mortality was recorded at the end of the brood cycle. Compensation indices and brood termination rates also showed similar effects. Overall, it is concluded that thiamethoxam at the recommended dose i.e. 25 g a.i. ha−1 did not affect the brood which was reared 7 days after the application. [ABSTRACT FROM AUTHOR]

BACKGROUND: To improve integrated pest management (IPM) performance it is essential to assess pesticide side effects on host plants, insect pests, and natural enemies. The green peach aphid (Myzus persicae Sulzer) is a major insect pest that attacks various crops. Aphidius gifuensis is an essential natural enemy of M. persicae that has been applied effectively in controlling M. persicae. Thiamethoxam is a neonicotinoid pesticide widely used against insect pests. RESULTS: The current study showed the effect of thiamethoxam against Solanum tuberosum, M. persicae, and A. gefiuensis and the physiological and molecular response of the plants, aphids, and parasitoids after thiamethoxam application. Thiamethoxam affected the physical parameters of S. tuberosum and generated a variety of sublethal effects on M. persicae and A. gefiuensis, including nymph development time, adult longevity, and fertility. Our results showed that different thiamethoxam concentrations [0.1, 0.5, and 0.9 μm active ingredient (a.i.)/L] on different time durations (2, 6, and 10 days) increased the antioxidant enzyme activities SOD, POD, and CAT of S. tuberosum, M. persicae, and A. gefiuensis significantly compared with the control. Our results also showed that different thiamethoxam concentrations (0.1, 0.5, and 0.9 μm a.i./L) on different time durations (2, 6, and 10 days) increased the expression of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), acetylcholinesterase (AChE), carboxylesterase (CarE) and glutathione‐S‐transferase (GST) genes of S. tuberosum, M. persicae, and A. gefiuensis compared with the control. CONCLUSION: Our findings reveal that using thiamethoxam at suitable concentrations and time durations for host plants and natural enemies may enhance natural control through the conservation of natural enemies by overcoming any fitness disadvantages. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

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Synthetic organic insecticides such as pyrethroids, organophosphates, neonicotinoids, and others have the potential to disrupt ecosystems and are often toxic to humans. Thiamethoxam (TMX), a neonicotinoid insecticide , is a widely used insecticide with neurotoxic potential. l-Carnitine (LC) is regarded as the "gatekeeper" in charge of allowing long-chain fatty acids into cell mitochondria. LC is an endogenous chemical that is renowned for its prospective biological activity in addition to its role in energy metabolism. This study investigated the protective effects of LC against TMX-induced neurotoxicity in male Wistar rats. For 28 days, animals were divided into four groups and treated daily with either LC (300 mg/kg), TMX (100 mg/kg), or both at the aforementioned doses. Our results revealed marked serum lipid profile and electrolyte changes, declines in brain antioxidants and neurotransmitters (acetylcholine, dopamine, and serotonin levels) with elevations in thiobarbituric acid reactive substances and proinflammatory cytokine levels, as well as acetylcholinesterase and monoamine oxidase brain activity in TMX-treated rats. TMX also increased the expression of caspase-3 and glial fibrillary acidic protein. In contrast, pretreatment with LC attenuated TMX-induced brain injury by suppressing oxidative stress and proinflammatory cytokines and modulating neurotransmitter levels. It also ameliorated the expression of apoptotic and astrogliosis markers. It could be concluded that LC has antioxidant, anti-inflammatory, anti-astrogliosis, and anti-apoptotic potential against TMX neurotoxicity. [ABSTRACT FROM AUTHOR]

An experiment was conducted to study the bioefficacy of six different insecticides (thiamethoxam 25 WG @ 0.01%, thiacloprid 21.7 SC @ 0.0032%, buprofezin 25EC @ 0.05%, spinosad 48 SC @ 0.017%, chlorantraniliprole 18.5 SC @ 0.007% and fenpropathrin 30 EC @ 0.01%) with a control (water spray) against sucking pests, viz., shoot and fruit borers, jassids, whiteflies and aphids, and harvest time residues in brinjal (Surti Ravaiya) at the College Farm, North Asian University, and Navsari during summer-2020. Among the different insecticides evaluated, chlorantraniliprole and spinosad were the most effective, fenpropathrin and buprofezin were the least effective insecticides against shoot and fruit borers, respectively. Thiamethoxam and thiacloprid were the most effective agents. Fenpropathrin and buprofezin were the least effective against whiteflies, jassids and aphids. After two hours of spray, the initial deposition order of the experimental insecticides was buprofezin (10.382 mg/kg) > fenpropathrin (5.602 mg/kg) > chlorantraniliprole (5.097 mg/kg) > thiamethoxam (4.886 mg/kg) > spinosad (3.984 mg/kg) > thiacloprid (3.332 mg/kg), while after 4 days of spray, the residue status of the brinjal fruit was in the order of fenpropathrin (0.539 mg/kg) > chlorantraniliprole (0.154 mg/kg) > thiacloprid (0.127 mg/kg) > thiamethoxam (0.099 mg/kg) > buprofezin (0.076 mg/kg) > spinosad (BDL). Overall, the highest percentage degradation of insecticide residues in brinjal fruits was registered with spinosad (100%), followed by buprofezin (99.26%), thiamethoxam (97.97%), chlorantraniliprole (96.97%), thiacloprid (96.18%) and fenpropathrin (90.37%) after 4 days of II spray. [ABSTRACT FROM AUTHOR]

Objective: Thiamethoxam (TMX) is a systemic insecticide used to combat plant pests that might significantly affect food security. Therefore, the current study aimed to evaluate its mammalian toxicity against male albino rats following short-term administration of sublethal doses. Methods: Two groups, control and treatment rats (eight males each), were orally administered distilled water and 1/20 LD50 (78.0 mg/kg B.W.) doses of TMX daily for 14 days. The biochemical, hematological, genotoxic, and histopathological responses were subsequently described. Results: The results revealed significant decreases in the specific activities of acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and Mg+-ATPase in the TMX-treated rats compared to those in the control group. Additionally, alterations in blood parameters were reported for treated individuals. Significant increases in the number of tailings (14%), tail length (3.43 µm), tail DNA (3.62%), and tail moment (12.56%) as well as the frequency of micronucleated erythrocytes (MNs) were found in the TMX-treated animals. Moreover, transmission electron microscopy (TEM) of blood samples revealed swollen mitochondria with light-dense cristae, vacuoles (V), nuclei (N) (contained migrated chromatin), and rough endoplasmic reticulum (RER) in comparison to the firm structure of the negative control. Conclusion: TMX exposure, especially at low doses, is an alarming sign of possible health hazards. [ABSTRACT FROM AUTHOR]

The impact of eight pesticides on the transmission of Tomato leaf curl virus (ToLCV) by the whitefly, Bemisia tabaci Gennadius to tomato, Lycopersicon esculentum (Miller), was studied in the field using a randomized block design. Differences in performance were anticipated because these eight insecticides comprise distinct mechanism of action including both contact and systemic. Increased insecticide efficacy is necessary, particularly in regions with conducive weather conditions that support a healthy whitefly population, to effectively manage the population. There is a need to vary the insecticides used in order to reduce the emergence of resistance in the whitefly population due to the extensive usage of a single mechanism of action for whitefly control. The foliar spray of insecticides was done when first incidence of whitefly was noticed in the field with 15 days of interval. The studies on effect of different insecticides in the management of ToLCV disease through the controlling whitefly population, we evaluated that Chlorantraniliprole 8.8% + Thiomethaxam 17.5% SC was effective in sustaining the yield by reducing the incidence of disease and whitefly population during both the years followed by Spirotetramat 11.01% + Imidacloprid 11.01% SC, Thiamethoxam 12.6% + Lambda cyhalothrin 9.5% ZC and Cyantraniliprole 10.26% OD, respectively. [ABSTRACT FROM AUTHOR]

An effective modified pre-concentration technique, namely Cloud Point Extraction (CPE) coupled with QuEChERS (quick, easy, cheap, effective, rugged, and safe)), was developed to extract and clean up four neonicotinoid pesticide residues (nitenpyram, imidacloprid, thiamethoxam, and thiacloprid) from honey samples. Two cloud point processes were performed, whereby Triton™ X-114 was used to extract neonicotinoid residues into the surfactant-rich phase and the analytes were then transferred into an alkaline solution by ultrasonication prior to clean-up via QuEChERS method. Numerous variables affecting extraction performance were investigated, including surfactant type and concentration, salt type and content, back-extraction agent type and concentration, solvent type, QuEChERS salt quantity, and incubation temperature and time. Ultra-high-performance liquid chromatography-tandem mass spectrometry triple-quadrupole (UHPLC-MS/MS) (QQQ) was used for analysis. The limits of detection (LODs) and quantification limits (LOQs) were 0.13 to 0.18 μg kg−1 and 0.2 to 2.3 μg kg−1 respectively. The overall recoveries of all target compounds were between 85.3% to 104.5%, and excellent repeatability was achieved with relative standard deviations (RSD) ranging from 2.0% to 11.5%. The proposed extraction approach successfully detected trace amounts of neonicotinoids in honey samples obtained from local markets. [ABSTRACT FROM AUTHOR]

Agrochemical exposure is a major contributor to ecological declines worldwide, including the loss of crucial pollinator species. In addition to direct toxicity, field-relevant doses of pesticides can increase species' vulnerabilities to other stressors, including parasites. Experimental field demonstrations of potential interactive effects of pesticides and additional stressors are rare, as are tests of mechanisms via which pollinators tolerate pesticides. Here, we controlled honey bee colony exposure to field-relevant concentrations of 2 neonicotinoid insecticides (clothianidin and thiamethoxam) in pollen and simultaneously manipulated intracolony genetic heterogeneity. We showed that exposure increased rates of Varroa destructor (Anderson and Trueman) parasitism and that while increased genetic heterogeneity overall improved survivability, it did not reduce the negative effect size of neonicotinoid exposure. This study is, to our knowledge, the first experimental field demonstration of how neonicotinoid exposure can increase V. destructor populations in honey bees and also demonstrates that colony genetic diversity cannot mitigate the effects of neonicotinoid pesticides. [ABSTRACT FROM AUTHOR]

Nitro-substituted neonicotinoid insecticides have been widely used until recently to control a range of important agricultural pests. Growing concerns about thiamethoxam's toxicity to pollinators have led to its use being restricted or to it even being banned in some countries. Nevertheless, in Asia, Africa, Southeast Europe, and South America thiamethoxam is still used. Although thiamethoxam has been intensively studied all over the world, its dissipation dynamics have not been studied in depth. The subject of the present study was to (1) develop and validate a QuEChERS/LC-MS/MS protocol for the determination of thiamethoxam and its main metabolite clothianidin in samples of young oilseed rape plants with high chlorophyll content, and (2) make a comparison of the degradation behaviors of thiamethoxam and clothianidin in two crops of winter oilseed rape, cultivated on soils with different pH. For determination of thiamethoxam and clothianidin in plant material with high chlorophyll content, a QuEChERS/LC–MS/MS protocol enabling the detection of low levels of compound concentrations was developed. The proposed clean-up protocol provided recoveries within the range of 92–98% for the compounds under analysis. Precision, calculated as relative standard deviation, was below 20%. Satisfactory linearity of the method was obtained in the concentration range under analysis (0.001–1.0 mg kg−1). Differences in degradation of both insecticides, depending on the physico-chemical properties of the soil, were observed. Thiamethoxam and clothianidin residues disappeared in plants very quickly, and they were not detected below the limit of quantitation in oilseed rape at the flowering stage. [ABSTRACT FROM AUTHOR]

Pesticides ensure greater productivity in less time; however, they spread beyond the perimeters to which they are applied to reach non-target organisms, thereby affecting plant, animal, and human health. Thiamethoxam (TMX) is considered to be one of the main agents responsible for poisoning bees and potentially contaminating surface and groundwater. Conventional water-treatment protocols are unable to degrade thiamethoxam; therefore, electrochemically advanced oxidative processes (EAOPs) have become promising alternatives owing to their ease of operation and cost-effectiveness. Herein, we examined the use of EAOPs to oxidize thiamethoxam in commercial Actara® and analyzed treatment efficiencies through phytotoxicity studies using cucumber and maize seeds as bioindicators. In addition, the cost of each process was analyzed based on the resulting current efficiency. The treated solutions were used to germinate seeds that were analyzed for total protein, hydrogen peroxide, lipid peroxidation (MDA), superoxide dismutase (SOD), and catalase (CAT) activities. EAOPs were found to effectively oxidize TMX, with more than 50% degraded and 80% COD removed under all treatment conditions, even when the commercial product was used. The photoelectro-Fenton process using 10 mg L−1 FeSO4 and 100 mg L−1 H2O2 exhibited the best results, with 79% of the TMX degraded and 83% of the COD removed, additionally exhibiting the lowest estimated operating cost (USD 1.01 dm−3). Higher enzymatic SOD and CAT activities, total protein content, and H2O2 concentration were observed; however, no significant changes in MDA were recorded. This treatment protocol effectively oxidizes TMX and reduces its phytotoxicity in maize and cucumber seedlings. [ABSTRACT FROM AUTHOR]

After decades of development, neonicotinoids were widely used in Hungarian sugar beet production and seeds included thiamethoxam treatment by 2019 increasing protection against early spring pests. In Hungary, neonicotides' influence on bee health led to their removal of emergency authorization. In the absence of thiamethoxam in 2020, experience showed that multiple treatments were needed to protect beet from pests early spring pests. Repeated applications of mostly pyrethroids have proved suitable; however, in sugar beet, this has resulted in a multiple increase in environmental stress and honey bee mortality, as well as increased input values. The aim of this work is to explore the current state of production and collect new alternative options for applying effectively in Hungarian sugar beet production technology, against early spring pests. [ABSTRACT FROM AUTHOR]

The persistence in the environment and possible harmful effects of neonicotinoid insecticides have raised some concerns, which have led to the proposal of various measures for their remediation. The aim of this work was to study the elimination of five neonicotinoids (thiamethoxam (THM), imidacloprid (IMI), clothianidin (CLO), thiacloprid (THC), and acetamiprid (ACE)) using ferrate (Fe(VI)) as the oxidizing agent. Firstly, second-order rate constants for the reactions of neonicotinoids with Fe(VI) were determined at different pHs. The most reactive compound was THC, with a rate constant of 400 ± 43 M−1 s−1 at pH 8 (the optimum pH considering the predominance of the most reactive species (HFeO4−) and the decreasing self-decomposition of Fe(VI) with pH), followed by CLO (10.7 ± 1.7 M−1 s−1), THM (9.7 ± 0.7 M−1 s−1), and IMI (2.5 ± 0.6 M−1 s−1). ACE did not significantly react with Fe(VI). The oxidation of the selected pollutants in secondary effluents by Fe(VI) was rather slow, and only THC could be efficiently removed. The presence of natural organic matter (NOM) exerted a negative influence on the removal of the neonicotinoids of moderate reactivity with Fe(VI) (CLO, THM, and IMI). The additional presence of peroxymonosulfate (Fe(VI)/PMS system) slightly increased the removal of neonicotinoids due to the formation of hydroxyl and sulfate radicals. Finally, the application of the Fe(VI)/sulfite system considerably increased the oxidation rate of the selected pollutants, with enhanced formation of hydroxyl and, especially, sulfate radicals. Overall, these results suggest that the Fe(VI)/sulfite system has significant potential to address environmental and health concerns associated with neonicotinoids in water sources with low NOM content. [ABSTRACT FROM AUTHOR]

The insecticide known as neonicotinoid has negative impacts on the ecosystem, human health, and the environment; specifically, its effects on the relationship between crop yields and the death rate of natural pollinators, such as bees, affect food security. The active ingredients in neonicotinoids include imidacloprid, clothianidin, thiamethoxam, acetamiprid, sulfoxaflor, and thiacloprid, which are sold under various trade names. For many of the components of these toxic insecticides, patents have been expired; however, farmers and consumers who continue to use these chemicals are unaware of the products' toxicity and the environmental effects they have. Thus, agricultural industries are required to consider diverse methods to minimize neonicotinoid use in farming operations and move away from the current prevailing methods. In this short review, the negative effects of neonicotinoid use; the toxic components, health effects, and environmental regulations of neonicotinoids; and sustainable methods to minimize their use are examined. [ABSTRACT FROM AUTHOR]

Pesticide exposure patterns tested in laboratory bioassays often do not match real-world pesticide exposure profiles in edge-of-field waterbodies. Toxicokinetic–toxicodynamic (TKTD) models are therefore increasingly used, as they allow for predictions of the toxic effects under actual time-variable field exposures. The TKTD models from the General Unified Threshold models of Survival (GUTS), for example, are considered ready for use by regulators for calculating the survival rates for any time-variable exposure profile. However, questions remain regarding their predictive power for compounds showing increased toxicity over time, such as neonicotinoid insecticides. The aim of the present study was therefore to compare the GUTS-predicted 28 d toxicity values of three neonicotinoids (imidacloprid, clothianidin, and thiamethoxam) for the common New Zealand mayfly genus Deleatidium spp. with those observed in a previously published study. Overall, the GUTS modeling results underestimated the toxicity values derived experimentally. From the three neonicotinoids, clothianidin showed the best fit between the estimated and observed 28 d LC50 (median-lethal-concentration) values. Shortcomings of the modeling exercise, future research needs, and implications for the application of GUTS models in regulatory risk assessment are discussed. [ABSTRACT FROM AUTHOR]

The application of perovskite lanthanum ferrite (LaFeO3) as a photocatalyst has shown significant potential in the removal of persistent organic and inorganic contaminants. In the present research, LaFeO3 and various composites consisting of LaFeO3 and TiO2 were prepared. The photocatalytic efficiency of the produced catalysts was assessed by measuring their effectiveness in degrading thiamethoxam, a pesticide belonging to the second generation of neonicotinoids. Experimental investigations were carried out to examine the impact of various factors on the degradation process, including variables like concentration of thiamethoxam, catalyst amount, and pH level. The produced catalysts were characterized by various techniques, including field emission scanning electron microscopy (FESEM), Brunauer–Emmett–Teller (BET) analysis, X-ray diffraction (XRD), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS). The highest degradation rates were observed when using the synthesized catalyst, 1% LaFeO3/TiO2 (LFTO1), under both UV-C and direct sunlight conditions. This performance outperformed TiO2 and bare LaFeO3. When exposed to ultraviolet (UV-C) radiation at an intensity of 15 W m−2 and under neutral pH conditions, LFTO1 achieved approximately 97% degradation, while under direct sunlight, the LFTO1 photocatalyst exhibited a degradation rate of 79% within a 120-min reaction period. The enhanced activity of LFTO1 could be attributed to its increased surface area, reduced bandgap, and lower electron–hole recombination. The investigation of reaction kinetics showed that the degradation of thiamethoxam followed a pseudo-first-order rate law. Furthermore, LFTO1 can be employed up to 5 times without experiencing any loss in its catalytic activity, thus confirming its long-term utility. [ABSTRACT FROM AUTHOR]

Background: Rice is one of the most common cereal crops in India, which has been found attacked by several insect pests including hoppers, stem borer, leaf folder, gall midge and ear head bugs. Farmers typically employ insecticides as preventative and curative management which causes needless issues. Although integrated pest management (IPM) has been recommended to nullify the ill effects of chemicals pesticides, farmers are hesitant to employ the IPM's components and mostly rely on pesticides. IPM integrates knowledge-based techniques of biological, cultural, physical, host plant resistance and chemical control strategies in order to limit pest populations considered economically acceptable. Present investigation was conducted to evaluate the effectiveness of IPM strategy improving upon the crop productivity. Methods: An Integrated Pest Management (IPM) module comprising of spacing, introduction of natural enemies, application of botanicals, entomopathogenic fungi, installation of yellow sticky traps and chemical pesticide (Thiamethoxam) was assessed in comparison with Farmers Practice (FP) (usual routine followed by the farmer during the cropping season) in the farmer's fields. Result: The pooled mean data of per cent leaf incidence by Nephotettix virescens ranged between 4.59-6.25% during the two years research in IPM module, while in farmers practices mean leaf damage varied between 8.09-8.61%. Similarly, the leaf damage caused by Nilaparvata lugens ranged between 4.88-7.61% as compared to 8.64-10% in the farmers practices. The BC ration was recorded to be 1: 7.6 and 1:6.85 during 2018 and 2019, respectively. [ABSTRACT FROM AUTHOR]

Foliar application of cyantraniliprole @ 60 g a.i ha− 1 was found most effective and statistically superior to standard checks imidacloprid and thiamethoxam in reducing Diaphorina citri population in kinnow mandarin upto 14 days of treatment. Thus the nature and amounts of active metabolites of cyantraniliprole used in kinnow are set to ensure the safety of the consumers and environment. Hence residue of cyantraniliprole at effective dose i.e. 60 g a.i ha− 1 and double of effective dose i.e. 120 g a.i ha− 1. using 1000 L of water was estimated from kinnow fruits and soil. The average initial deposit of cyantraniliprole in kinnow fruits were 0.254 and 0.415 mg kg− 1 which dissipated to the extent of 95.28 and 95.15% in the respective doses after 10 days and to below detectable limits after 15 days of spray. The residue of cyantraniliprole in soil was found below detectable limits after 10 days of spray. It is concluded that cyantraniliprole can be used in D. citri management programme in kinnow mandarin and the pre-harvest interval recommended for safe consumption of kinnow fruits was observed to be 15 days. [ABSTRACT FROM AUTHOR]

Rapeseed- mustard is an important source of edible oil but vulnerable to attack by various insect pests. More than three dozen insect pests are known to be related with rapeseed mustard crop in India. Among them, mustard aphid, Lipaphis erysimi (Kalt.) is a major pest on rapeseed-mustard. Bio-efficacy of PAU homemade neem extract (PAU HMNE) @ 5.0, 7.5 and 10.0 L ha−1 along with standard check, Actara (thiamethoxam 25 WG) @ 100 g ha−1 was tested against L. erysimi on gobhi sarson under organic farming conditions. All treatments were applied twice, first when aphid population reached at economic threshold level, ETL (50–60 aphids per 10 cm terminal portion of the central shoot of plant) and second after 7 days of first spray. Water spray and untreated control were kept for the comparison purpose. Three replications were kept for all the treatments. Aphid incidence was recorded on 10 cm terminal portion of central shoot from 10 randomly selected tagged plants per plot. On pooled mean basis, Actara 25 WG @ 100 g ha−1 was found to be most effective against mustard aphid offering highest per cent reduction over control (PROC) viz. 85.01- 94.67 and 83.75–89.66% during 2020–21 and 2021–22, respectively, but it also registered highest predators' mortality. In contrast, a locally prepared neem extract, PAU HMNE @ 10.0 L ha−1 was next to record high PROC, i.e., 37.44 to 48.28% and 43.57 to 50.06% in 2020–21 and 2021–22, respectively, and highest predators' population. A highest seed yield of mustard (14.80 and 16.85 q ha−1) was marked in Actara 25 WG @ 10.0 L followed by PAU HMNE @ 10.0 L (13.83 and 16.24 q ha−1) over the untreated control plots with lowest seed yield (11.30 and 14.60 q ha−1) in 2020–21 and 2021–22, respectively. [ABSTRACT FROM AUTHOR]

Plant growth and physiology can be affected by environmental and chemical factors that have the potential to influence yields. Among the factors that influence plant growth, neonicotinoid seed treatments have shown significant effects on plant growth, particularly in cotton. The dual benefits seen from neonicotinoids on plant growth and insect control show promise in improving cotton yields but little is known about how different seed treatments affect seedling physiology. A greenhouse experiment was undertaken to investigate how three neonicotinoid seed treatments (clothianidin, thiamethoxam, and imidacloprid) affect the physiology and growth of cotton seedlings in controlled environmental conditions. A randomized complete block design was used to examine seed treatments and an untreated control. Cotton seeds were treated, grown, and evaluated for physiological changes until the fifth true leaf-stage and measurements were taken at each of these stages. Data were collected on plant height, shoot fresh weight, leaf area, root length, and root biomass. In addition, chlorophyll pigments and nutrient analysis were performed on cotton seedlings. The seedlings of imidacloprid treated seeds had greater height, shoot fresh mass, leaf area, and relative growth rate by the fifth true leaf stage compared to other treated plants; however, clothianidin showed comparative performance at earlier stages in plant development that equilibrated over time. While all neonicotinoid seed treatments showed positive effects, imidacloprid showed the most potential as a bioactivator on plant growth. [ABSTRACT FROM AUTHOR]