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The diamondback moth (DBM), Plutella xylostella (L.), is responsible for extensive losses in brassicas' production, with its control heavily relying on the use of insecticides. The imbricated brassica's leaves on the stem provide a suitable habitat for the ring‐legged earwig, Euborellia annulipes (Lucas), to attack DBM larvae and pupae. The study focused on the combination of the earwig with indoxacarb and cyantraniliprole against DBM, as these insecticides target chewing and sucking sap pests infesting Brassica crops, respectively. These insecticides were tested against adult earwigs, 5th instar nymphs and predation upon DBM. When exposed to the recommended rates, the survival rates for nymphs were 74%, 100% and 96% in the cyantraniliprole, indoxacarb and control groups, respectively, and over 90% for adults. When 5th instar earwig nymphs were exposed to cyantraniliprole, they took 16.3 days to develop compared to indoxacarb (3.4 days) or the control group (3.2 days). Furthermore, females exposed to cyantraniliprole required more time to initiate oviposition and produced fewer eggs in the first egg batch. Despite that, the egg‐hatching rate was greater than 80% in all treatments. Female earwigs confined to indoxacarb‐ or cyantraniliprole‐treated or untreated leaves and DBM larvae maintained similar survival but lower consumption of DBM larvae when exposed to cyantraniliprole. The findings revealed that cyantraniliprole weakened the potential of the ring‐legged earwig to control DBM. On the other hand, indoxacarb was harmless to the earwig and showed additive mortality for the pest. Therefore, indoxacarb seems compatible with E. annulipes, while cyantraniliprole has a sublethal effect that slows down development and reproduction. [ABSTRACT FROM AUTHOR]

The diamondback moth, Plutella xylostella (Linnaeus), is one of the most important insect pests of Brassica crops worldwide. In October 2016, outbreaks of an invasive P. xylostella population and unexpected control failures occurred on broccoli and cauliflower crops throughout all vegetable-growing regions in Arizona. Nineteen populations of Plutella xylostella were collected from 2016 to 2021 from various commercial cauliflower fields in Yuma and Scottsdale, Arizona, and from experimental broccoli plots at the University of Arizona, Yuma Agricultural Center (UAYAC), Yuma, Arizona. Populations collected from the commercial cauliflower fields had been transplanted with seedlings produced in a local Yuma nursery in 2016 and Salinas, CA in 2017 to 2018, whereas experimental broccoli plots were direct seeded. These populations were evaluated for their susceptibility to chlorantraniliprole, spinetoram, emamectin benzoate, and cyantraniliprole. In this study, field rate laboratory bioassays, serial dilution laboratory bioassays, and field efficacy spray experiments were performed. The field rate laboratory bioassay results showed that spinetoram, emamectin benzoate, and cyantraniliprole remained effective at controlling P. xylostella, but chlorantraniliprole did not control P. xylostella at the field rate. Additionally, serial dilution bioassays confirmed significant levels of cyantraniliprole and chlorantraniliprole resistance in the P. xylostella populations collected from transplanted cauliflower fields. However, the results of the multiyear/growing-seasons study monitoring the susceptibility of P. xylostella populations collected from direct-seeded broccoli and field efficacy trials conducted at the UAYAC indicated that the resistance to diamide insecticides was neither uniform nor persistent following the 2016 outbreak. Nevertheless, the risk for P. xylostella resistance in Arizona vegetable-growing regions exists, particularly in Brassica transplants. Therefore, we recommend that Arizona Brassica growers remain vigilant and practice rigorous insecticide resistance management to offset the development of resistance. [ABSTRACT FROM AUTHOR]

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]

Reaction of lithium 1,3‐diamidopropane Li2(TripNCN) (TripNCN=[{(Trip)NCH2}2CH2]2−, Trip=2,4,6‐triisopropylphenyl) with BeBr2(OEt2)2 gave the diamido beryllium complex, [(TripNCN)Be(OEt2)]. Deprotonation reactions between the bulkier 1,3‐diaminopropane (TCHPNCN)H2 (TCHPNCN=[{(TCHP)NCH2}2CH2]2−, TCHP=2,4,6‐tricyclohexylphenyl) and magnesium alkyls afforded the adduct complexes [(TCHPNCN)Mg(OEt2)] and [(TCHPNCN)Mg(THF)2], depending on the reaction conditions employed. Treating [(TCHPNCN)Mg(THF)2] with the N‐heterocyclic carbene :C{(MeNCMe)2} (TMC) gave [(TCHPNCN)Mg(TMC)2] via substitution of the THF ligands. Reactions of (ArNCN)H2 (Ar=Trip or TCHP) with Mg{CH2(SiMe3)}2, in the absence of Lewis bases, yielded the N‐bridged dimers [{(ArNCN)Mg}2]. Salt metathesis reactions between alkali metal salts M2(TCHPNCN) (M=Li or K) and CaI2 or SrI2 led to the THF adduct compounds [(TCHPNCN)Ca(THF)3] and [(TCHPNCN)Sr(THF)4], the differing number of THF ligands in which is a result of the different sizes of the metals involved. The described complexes hold potential as precursors to kinetically protected, low oxidation state group 2 metal species. [ABSTRACT FROM AUTHOR]

Lymnaea stagnalis is an ecologically important, stress‐sensitive, freshwater mollusk that is at risk for exposure to insecticides via agricultural practices. We provide insight into the impact insecticides have on L. stagnalis by comparing specific behaviors including feeding, locomotion, shell regeneration, and cognition between snails collected at two different sites: one contaminated by insecticides and one not. We hypothesized that each of the behaviors would be altered in the insecticide‐exposed snails and that similar alterations would be induced when control snails were exposed to the contaminated environment. We found no significant differences in locomotion, feeding, and shell regeneration of insecticide‐exposed L. stagnalis compared with nonexposed individuals. Significant changes in feeding and shell repair were observed in nonexposed snails inhabiting insecticide‐contaminated pond water. Most importantly, snails maintained and trained in insecticide‐contaminated pond water did not form configural learning, but this cognitive deficit was reversed when these snails were maintained in insecticide‐free pond water. Our findings conclude that insecticides have a primarily negative impact on this higher form of cognition in L. stagnalis. Environ Toxicol Chem 2023;42:2466–2477. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

ABSTRACT The bacterium Bacillus subtilis is of high importance both as a model organism for Gram-positive bacteria and as an industrial workhorse in the production of biomolecules. In recent years, advancements have been made to engineer the bacterium even further toward industrial applications. In this study, we present a novel screening method for mutant libraries using diamide, an oxidizing agent that binds free thiols and creates disulfide bonds between them, thereby causing a so-called “disulfide stress” in bacteria. The method shows promise to selectively identify phenotypes in B. subtilis with improved tolerance toward oxidative and disulfide-associated stress. Phenotypes initially identified by transposon mutagenesis were recreated through targeted gene deletions. Among the resulting deletion mutants, the largest difference in diamide tolerance compared to the parental strain was observed for pfkA and ribT deletion strains. A proteomics analysis showed that diamide tolerance can be achieved through different routes involving increased expression of stress management proteins and reduced availability or activity of the RNA degradosome. We conclude that our screening method allows the facile identification of Bacillus strains with improved oxidative stress tolerance phenotypes. IMPORTANCE During their life cycle, bacteria are exposed to a range of different stresses that need to be managed appropriately in order to ensure their growth and viability. This applies not only to bacteria in their natural habitats but also to bacteria employed in biotechnological production processes. Oxidative stress is one of these stresses that may originate either from bacterial metabolism or external factors. In biotechnological settings, it is of critical importance that production strains are resistant to oxidative stresses. Accordingly, this also applies to the major industrial cell factory Bacillus subtilis. In the present study, we, therefore, developed a screen for B. subtilis strains with enhanced oxidative stress tolerance. The results show that our approach is feasible and time-, space-, and resource-efficient. We, therefore, anticipate that it will enhance the development of more robust industrial production strains with improved robustness under conditions of oxidative stress.

We tested the hypothesis that systemic insecticides should be effective against sap-sucking insects which acquire toxicants from the tissues of treated plants whereas their natural enemies should be unaffected. Under this hypothesis, the suppression of early-season cotton insect infestations and the interaction with predatory insects of different feeding habits were investigated using the systemic insecticides cyantraniliprole and thiamethoxam through foliar application (FA) and seed treatment (ST). Insecticide residues on ST plants were quantified at 12, 22, and 32 days after emergence (DAE) to assess the survival of the zoophytophagous (Orius insidiosus) and chewing (Eriopis connexa), both predators of early-season cotton pests, when confined on treated plant material. Residues of both insecticides were detected on ST plants, but the level was significantly reduced between 12 and 22 DAE and not detected at 32 DAE. Both insecticides offered aphid suppression but with a more prolonged effect of thiamethoxam, and both were ineffective against high thrips infestation. Whitefly densities were at or below economic threshold in all treatments after the expected control provided through ST. Cyantraniliprole was compatible with both predators (> 92% survival) through FA and ST. Thiamethoxam was highly toxic to O. insidiosus through FA (0.5% survival) and diminished through ST (27.6% survival). At 22 DAE, O. insidiosus still showed lower survival with FA than ST with thiamethoxam (51.4% vs. 90.7%). Regardless of the insecticide used in ST, supplementary FA was required against early-season pests. The results show that ecological selectivity through seed treatment depends on the feeding habit of the predator and the insecticide applied. [ABSTRACT FROM AUTHOR]

Blood flow in the microcirculatory system is crucially affected by intrinsic red blood cell (RBC) properties, such as their deformability. In the smallest vessels of this network, RBCs adapt their shapes to the flow conditions. Although it is known that the age of RBCs modifies their physical properties, such as increased cytosol viscosity and altered viscoelastic membrane properties, the evolution of their shape-adapting abilities during senescence remains unclear. In this study, we investigated the effect of RBC properties on the microcapillary in vitro flow behavior and their characteristic shapes in microfluidic channels. For this, we fractioned RBCs from healthy donors according to their age. Moreover, the membranes of fresh RBCs were chemically rigidified using diamide to study the effect of isolated graded-membrane rigidity. Our results show that a fraction of stable, asymmetric, off-centered slipper-like cells at high velocities decreases with increasing age or diamide concentration. However, while old cells form an enhanced number of stable symmetric croissants at the channel centerline, this shape class is suppressed for purely rigidified cells with diamide. Our study provides further knowledge about the distinct effects of age-related changes of intrinsic cell properties on the single-cell flow behavior of RBCs in confined flows due to inter-cellular age-related cell heterogeneity. [ABSTRACT FROM AUTHOR]

Circular dichroism (CD) spectroscopy is a powerful technique employed to study the structure of biomolecules. More accurate calculation of CD from first principles will aid both computational and experimental studies of protein structure and dynamics. We apply a diabatisation scheme to improve the description of nearest neighbour interactions between two electronic transitions (nπ* and πnbπ*) localised on each individual peptide bond (amide group) in a protein. These interactions are incorporated into DichroCalc, an exciton-based computational method to calculate CD, and yield improvements over the standard DichroCalc parameter set, particularly for calculation of CD for important secondary structural elements such as an α helix. [ABSTRACT FROM AUTHOR]

Coccinella septempunctata (ladybird) is an extremely important natural predator that feeds on aphids. An assessment of the toxicity of pesticides on environmental organisms is an essential component of Integrated Pest Management (IPM) strategies. This study evaluated diamide insecticides' toxicity at lethal and 30% lethal doses (LR30) against C. septempunctata larvae. The pre-imaginal median lethal doses (LR50) of chlorantraniliprole 10% SC, tetrachlorantraniliprole 10% SC, and broflanilide 10% SC were calculated to be 42.078, 289.516, and 0.0943 g active ingredient (a.i.)/ha, respectively. The mortality tests demonstrated that chlorantraniliprole and tetrachlorantraniliprole are comparatively less toxic to C. septempunctata than broflanilide, which were detected to be highly toxic to C. septempunctata. The mortality rates of the groups treated with the three diamide insecticides tended to stabilize after 96 h, extending to the pre-imaginal stage. Furthermore, when compared to broflanilide, which had a much higher potential risk, the hazard quotient (HQ) values indicated that chlorantraniliprole and tetrachlorantraniliprole have a lower risk potential for C. septempunctata in farmland and off farmland. The LR30 dose induces abnormalities in the development phase 4th-instar larvae weight, pupal weight, and adult weight of treated C. septempunctata. The study emphasizes the importance of assessing the adverse effects of diamide insecticides on natural predator species that serve as biological control agents in agricultural IPM strategies. [ABSTRACT FROM AUTHOR]

The corn earworm, Helicoverpa zea (Boddie), is a major pest of row crops in the Southern United States. Control of this insect is dependent on preventative insecticidal transgenic crops and synthetic insecticide applications when damaging populations are encountered in the field. Recently, the use of chemicals from the diamide class of insecticides, particularly chlorantraniliprole, has been used to control unacceptable populations. Due to the increased importance of this active ingredient for control of corn earworms, populations of this insect from the Mississippi Delta have been monitored for susceptibilities annually since 2016. Overall, 58 populations of H. zea were examined for their susceptibility to chlorantraniliprole through diet-incorporated bioassays from 2016 to 2021. Based on probit analysis, there was only a 4-fold difference between the highest and lowest LC50 estimates for all populations tested. Through weights of 2nd and 3rd instar larvae, there appears to be a substantial fitness cost associated with surviving caterpillars that fed on various concentrations of chlorantraniliprole in bioassays, which is not captured through the yes or no response of typical survival analysis. Overall, there was not a detectable trend of reduced susceptibility to chlorantraniliprole over the course of the six-year study. [ABSTRACT FROM AUTHOR]

For over a decade, diamide insecticides have been effective against lepidopteran pests like beet armyworm, Spodoptera exigua (Hübner, 1808). However, the evolution of resistance poses a challenge to their sustainable use. We identified an I4790 M mutation in the S. exigua ryanodine receptor (RyR) gene, but its correlation with resistance varied across the field-collected Korean populations of S. exigua. RNA sequencing and differential gene expression analysis were performed to investigate other resistance mechanisms. Diamide-resistant and susceptible strains and F1 hybrids were compared by mapping RNA-seq reads to the S. exigua reference genome. CYP9A40 was identified as a critical gene in diamide resistance due to its high expression in the resistant strains. Synergist bioassays with piperonyl butoxide supported the role of P450s in diamide metabolic resistance in S. exigua. A strong positive correlation between CYP9A40 over-expression levels (up to 80-fold) and diamide LC 50 values was obtained for field-collected populations uniformly showing a 100% frequency of the RyR I4790 M target-site resistance allele. To validate the function of CYP9A40 in diamide detoxification, we recombinantly expressed the gene and tested its ability to bind and degrade chlorantraniliprole as a substrate. The results confirmed its catalytic role in diamide metabolism. CYP9A40 has been identified and validated to confer metabolic resistance in Korean S. exigua populations. It works alongside the RyR target-site I4790 M mutation to enhance diamide resistance. These mechanisms offer insights for resistance monitoring and support insecticide resistance management programs to improve control strategies for S. exigua. [Display omitted] • Explored alternative chlorantraniliprole resistance mechanisms beyond the I4790 M mutation in S. exigua. • Identified increased transcript levels of CYP9A40 in chlorantraniliprole-resistant strains. • Chlorantraniliprole is degraded by recombinantly expressed CYP9A40. • Established a correlation between CYP9A40 levels and chlorantraniliprole resistance. • Findings inform resistance monitoring and management in pest control strategies. [ABSTRACT FROM AUTHOR]

Thirty novel diamide compounds combining pyrazolyl and polyfluoro-substituted phenyl groups into alanine or 2-aminobutyric acid skeletons were designed and synthesized with pyflubumide as the lead compound to develop potent and environmentally friendly pesticides. The preliminary bioassay results indicated that the new compounds containing the para-hexa/heptafluoroisopropylphenyl moiety exhibit fungicidal, insecticidal, and acaricidal activities. This is the first time that the para-hexa/heptafluoroisopropylphenyl group is a key fragment of the fungicidal activity of new N-phenyl amide compounds. Most of the target compounds exhibited moderate to good insecticidal activity against Aphis craccivora at a concentration of 400 μg/mL, and some showed moderate activity at a concentration of 200 μg/mL; in particular, compounds I-4, II-a-10, and III-26 displayed higher than 78% lethal rates at 200 μg/mL. Compound II-a-14 exhibited a 61.1% inhibition at 200 μg/mL for Tetranychus cinnabarinus. In addition, some of the target compounds exhibited good insecticidal activities against Plutella xylostella at a concentration of 200 μg/mL; the mortalities of compounds I-1, and II-a-15 were 76.7% and 70.0%, respectively. Preliminary analysis of the structure–activity relationship (SAR) indicated that the insecticidal and acaricidal activities varied significantly depending on the type of substituent and substitution pattern. The fungicidal activity results showed that compounds I-1, II-a-10, II-a-17, and III-26 exhibited good antifungal effects. Enzymatic activity experiments and in vivo efficacy of compound II-a-10 were conducted and discussed. [ABSTRACT FROM AUTHOR]

The egg parasitoid Trichogramma japonicum (Hymenoptera: Trichogrammatidae) is used for biological control of lepidopteran pests, and it could be used for optimizing Integrated Pest Management (IPM) in rice crop. Chlorantraniliprole is a diamide insecticide broadly applied for pest control in rice cropping systems and it has been generally considered harmless to egg parasitoids. However, the impact of sublethal or low lethal concentrations of chlorantraniliprole on T. japonicum remains unclear. In this context, under laboratory conditions we assessed the acute toxicity of chlorantraniliprole on T. japonicum as well as sublethal effects of a low lethal concentration (LC10) on key biological traits of the parasitoid. In addition, we also evaluated the impact of chlorantraniliprole on the biocontrol service provided by T. japonicum on the pest Chilo suppressalis (Lepidoptera: Crambidae) under field conditions. The LC10 of chlorantraniliprole on adult parasitoids through exposure with residues was 0.110 mg/L, and this LC10 induced hormesis in exposed individuals; locomotory activity, respiratory metabolism and mass reproduction of T. japonicum were enhanced. Under field conditions, chlorantraniliprole led to increased biocontrol service provided by T. japonicum (reduced pest damage). These results can be useful for optimizing further the use of Trichogramma parasitoids into IPM in rice crops. It also hints the importance of carrying out careful risk-assessment of pesticide non-lethal effects under field conditions when developing IPM. [ABSTRACT FROM AUTHOR]

Broflanilide, a negative allosteric modulator of γ-aminobutyric acid (GABA)-gated chloride channel, is a novel diamide insecticide. It was mainly used for the control of lepidoptera and coleopteran pests at present, and it also exhibited high insecticidal activity against termites and flies. In this paper, the structure type, research process, mechanism of action, insecticidal activities, safety, and metabolic residue of broflanilide were mainly reviewed. Moreover, its development and application trends were also prospected. [ABSTRACT FROM AUTHOR]

A group of novel trimethoxyphenyl (TMP)-based analogues were synthesized by varying the azalactone ring of 2-(3,4-dimethoxyphenyl)-4-(3,4,5-trimethoxybenzylidene)oxazolone 1 and characterized using NMR spectral data as well as elemental microanalyses. All synthesized compounds were screened for their cytotoxic activity utilizing the hepatocellular carcinoma (HepG2) cell line. Compounds 9, 10 and 11 exhibited good cytotoxic potency with IC50 values ranging from 1.38 to 3.21 μM compared to podophyllotoxin (podo) as a reference compound. In addition, compounds 9, 10 and 11 exhibited potent inhibition of β-tubulin polymerization. DNA flow cytometry analysis of compound 9 shows cell cycle disturbance at the G2/M phase and a significant increase in Annexin-V-positive cells compared with the untreated control. Compound 9 was further studied regarding its apoptotic potential in HepG2 cells; it decreased the level of MMP and Bcl-2 as well as boosted the level of p53 and Bax compared with the control HepG2 cells. [ABSTRACT FROM AUTHOR]

The cotton bollworm Helicoverpa armigera (Lepidoptera: Noctuidae) is a significant pest in the world and it was identified in Brazil in 2013, causing severe economic losses. Recent studies showed a significant decrease in the susceptibility of H. armigera to diamide insecticides in Brazil. Understanding the genetic basis and mechanisms of the resistance are essential to develop proactive resistance management strategies. A laboratory strain of H. armigera resistant to the phthalic acid diamide flubendiamide (Flub-R) was selected from a field-collected population to characterize the resistance. The resistance ratio of the Flub-R strain was >50,000-fold. The inheritance pattern of the resistance was characterized as an autosomal dominant trait. Flub-R showed no cross-resistance to the anthranilic diamides chlorantraniliprole, cyantraniliprole or cyclaniliprole. Susceptible strain larvae that fed on flubendiamide-treated soybean leaves at field-recommended rates were killed while heterozygotes and Flub-R larvae showed a high survival and no reduction in the leaf consumption, confirming the functional dominance of the resistance. No indication of metabolic resistance was detected. The partial sequencing of ryanodine receptor (RyR) genes covering the transmembrane II to VI did not show any amino acid mutations, indicating the presence of a non-common resistance mechanism to diamide insecticides in the Flub-R strain. [ABSTRACT FROM AUTHOR]

A novel series of amides based TMP moiety was designed, synthesized and evaluated for their antiproliferative as well as enzyme inhibition activity. Compounds 6a and 6b showed remarkable cytotoxic activity against HepG2 cells with IC50 values 0.65 and 0.92 μM, respectively compared with SAHA and CA-4 as reference compounds. In addition, compound 6a demonstrated good HDAC-tubulin dual inhibition activity as it showed better HDAC activity as well as anti-tubulin activity. Moreover, compound 6a exhibited G2/M phase arrest and pre-G1 apoptosis as demonstrated by cell cycle analysis and Annexin V assays. Further apoptosis studies demonstrated that compound 6a boosted the level of caspase 3/7. Caspase 3/7 activation and apoptosis induction were evidenced by decrease in mitochondrial permeability suggesting that activation of caspase 3/7 may occur via mitochondrial apoptotic pathway. [ABSTRACT FROM AUTHOR]

The diamides, chlorantraniliprole (CHL) and cyantraniliprole (CYA), have been used as seed treatment agents against the fall armyworm (FAW), Spodoptera frugiperda in China. However, large-scale application of these two insecticides is prohibited because of their high cost. The neonicotinoid insecticides, clothianidin (CLO) and thiamethoxam (THI), are cheaper and widely used. In this study, we tested the efficacy of CHL + CLO and CYA + THI as seed treatment agents against FAW larvae both in laboratory and field conditions. Laboratory experiments showed that the two binary mixtures (both 240 g.a.i.100 kg−1 corn seeds) caused FAW mortality exceeded 84.00% at 14 days after seedling emergence (DAE). The mortality of the binary mixtures were similar to either CHL (300 g.a.i.100 kg−1corn seeds) or CYA (144 g a.i.100 kg−1corn seeds), but higher than CLO (120 g.a.i.100 Kg−1corn seeds) or THI (180 g a.i.100 kg−1corn seeds). Two independent field experiments showed that both binary mixtures resulted in above 68.00% control efficacy at 14 DAE, suggesting that these insecticidal combinations could effectively control FAW over a relative long period. In addition, both binary mixtures showed no negative effects on the growth and development of corn seedlings. The residues of binary mixtures in corn leave were also lower at 28 DAE as compared to residues in CHL or CYA alone. Most importantly, the costs of CHL + CLO were reduced up to 50% and CYA + THI up to 20% when compared to singly used chemical. Totally, our results indicated that CHL + CLO and CYA + THI had the same control efficacy as CHL or CYA alone, but with much lower cost.

In order to discover insecticide leads with novel structures, a variety of cyclopropanecarboxylic acid-containing active fragments were introduced into diamide insecticides. 21 novel diamide derivatives were designed and synthesized. Their structures were characterized by nuclear magnetic resonance spectroscopy (NMR) and high resolution mass spectrometry (HRMS). And their biological activities against Aphis craccivora, Mythimna separate, Fusarium graminearum and Blumeria graminis were evaluated. The results suggestted that most of our anthranilic diamides had low fungicidal activities on the two fungi and good insecticidal activities against the two insect targets. And at the concentration of 500 mg/L, 10h exhibited a mortality rate of 90% against A. craccivora, while 10k possessed a rate of 100% against M. separate. Both two derivatives could be further optimized as potential insecticide leads. [ABSTRACT FROM AUTHOR]

Chlorantraniliprole susceptibility was determined in diet-incorporation bioassays for six fall armyworm, Spodoptera frugiperda (J. E. Smith), populations feeding on sweet corn, Zea mays L., in southern Florida between 2017 and 2019. The LC50 and LC90 values of these populations estimated using probit analyses ranged from 0.022 to 0.084 ppm and 0.112 to 0.471 ppm, respectively. Thus, susceptibility levels among the six field populations varied, but to a relatively small extent, with approximately fourfold differences in LC50 and LC90 values between the most and least susceptible populations. These field populations were all less susceptible than a reference population maintained in the laboratory without prior exposure to chlorantraniliprole, with RR50 values between 5.3 and 20.1 and RR90 values between 14.3 and 60.3. These results suggest reduced chlorantraniliprole susceptibility in S. frugiperda populations collected in Florida sweet corn relative to a reference laboratory population. However, field experiments in 2017 and 2019 showed that foliar applications of chlorantraniliprole reduced S. frugiperda injury and infestations to levels comparable to or lower than applications of indoxacarb, novaluron, or spinetoram. This study does not provide evidence of practical resistance to chlorantraniliprole in S. frugiperda infesting Florida sweet corn fields. [ABSTRACT FROM AUTHOR]

Coccinella septempunctata (ladybird) is an extremely important natural predator that feeds on aphids. An assessment of the toxicity of pesticides on environmental organisms is an essential component of Integrated Pest Management (IPM) strategies. This study evaluated diamide insecticides’ toxicity at lethal and 30% lethal doses (LR30) against C. septempunctata larvae. The pre-imaginal median lethal doses (LR50) of chlorantraniliprole 10% SC, tetrachlorantraniliprole 10% SC, and broflanilide 10% SC were calculated to be 42.078, 289.516, and 0.0943 g active ingredient (a.i.)/ha, respectively. The mortality tests demonstrated that chlorantraniliprole and tetrachlorantraniliprole are comparatively less toxic to C. septempunctata than broflanilide, which were detected to be highly toxic to C. septempunctata. The mortality rates of the groups treated with the three diamide insecticides tended to stabilize after 96 h, extending to the pre-imaginal stage. Furthermore, when compared to broflanilide, which had a much higher potential risk, the hazard quotient (HQ) values indicated that chlorantraniliprole and tetrachlorantraniliprole have a lower risk potential for C. septempunctata in farmland and off farmland. The LR30 dose induces abnormalities in the development phase 4th-instar larvae weight, pupal weight, and adult weight of treated C. septempunctata. The study emphasizes the importance of assessing the adverse effects of diamide insecticides on natural predator species that serve as biological control agents in agricultural IPM strategies.

[Display omitted] • Safeguarding young maize plants from infestation by fall armyworm is of utmost importance. • Seed treatment with diamides was effective on early and mid-age caterpillars. • It is possible to protect the crop up to one month from emergence of seedlings through seed dressing with diamides. • Seed treatment may provide a more efficient and cost-effective alternative to foliar spray. The fall armyworm, Spodoptera frugiperda (J. E. Smith) is one of the major pests of maize worldwide. Farmers apply multiple rounds of pesticides within a single cropping season to control the fall armyworm. This leads to increased costs for plant protection and accelerates the selection pressure for evolution of resistance to various insecticide molecules in a short period. Hence, it is crucial to minimize the frequency of insecticide sprays on the crop. In this study we assessed the efficacy of seed treatment chemicals viz.- cyantraniliprole 19.8 % + thiamethoxam 19.8 % FS, chlorantraniliprole 62.5 % FS, and thiamethoxam 70 % WS against neonates and third instar larvae of S. frugiperda. Lab bioassays using leaves from seed treated plants were conducted. Results showed that thiamethoxam 70 % WS was completely ineffective. It was thus presumed that only cyantraniliprole contributed to the observed larval mortality in the combination chemical tested here. Although both cyantraniliprole and chlorantraniliprole were effective for up to a month, the latter consistently recorded greater larval mortality. As seed treatment is easy to practice, poses lower risk and economical, we recommend this application method, especially using chlorantraniliprole 62.5 % FS, as a part of the integrated pest management strategy to combat the fall armyworm in maize. [ABSTRACT FROM AUTHOR]

• Dytiscids are important top predators in many agricultural wetlands. • λ-cyhalothrin exhibited high toxicity to the dytiscid below field concentrations. • Chlorantraniliprole and thiamethoxam were safer to the dytiscid. • The dytiscid inclined to exit chlorantraniliprole-contaminated water once possible. Predaceous diving beetles (dytiscids) are important top insect predators in various natural, agricultural, and artificial water bodies. How they respond to human disturbances such as insecticide contamination to their habitats has been understudied. In this study, we investigated the lethal effects of lambda-cyhalothrin, chlorantraniliprole, and thiamethoxam at nominal field concentrations in 3 cm-deep water in a hypothetical paddy field (C i , 3) on adult Dytiscus sinensis Feng (Coleoptera: Dytiscidae). Lambda-cyhalothrin exhibited significant lethal effects on D. sinensis adults with its C i , 3 exceeding the 95 % confidence interval lower limits for 24, 48, 72, and 96 h- LC 99. Chlorantraniliprole and thiamethoxam showed no significant lethal effects on D. sinensis adults at their respective C i , 3 at 24, 48, or 72 h. Additionally, we assessed the temporal propensity of D. sinensis adults to exit water contaminated with chlorantraniliprole and thiamethoxam, respectively. There were significantly more individuals that temporally exited the chlorantraniliprole-contaminated water than clean water 30 min after placing a tile island in the test arena. Meanwhile, thiamethoxam-contaminated water did not repel significantly more individuals than clean water when observed at 10, 30, or 60 min. The study highlights the availability and importance of selecting safer insecticides for dytiscid conservation in agricultural and adjacent habitats, considering the potential of these water bodies becoming ecological traps that keep attracting and killing aquatic beneficials. The water-exiting behavior found indicates the capability of some wildlife to effectively avoid further exposure to toxicants. [ABSTRACT FROM AUTHOR]

Phthorimaea absoluta is an invasive solanaceous plant pest with highly devastating effects on tomato plant. Heavy reliance on insecticide use to tackle the pest has been linked to insecticide resistance selection in P. absoluta populations. To underline insights on P. absoluta insecticide resistance mechanisms to diamides and avermectins, we evaluated the transcriptomic profile of parental (field-collected) and F8 (lab-reared) populations. Furthermore, to screen for the presence of organophosphate and pyrethroid resistance, we assessed the gene expression levels of acetylcholinesterase (ace1) and para-type voltage-gated sodium channel (VGSG) genes in the F1 to F8 lab-reared progeny of diamide and avermectin exposed P. absoluta field-collected populations. The VGSG gene showed up-regulation in 12.5% and down-regulation in 87.5% of the screened populations, while ace1 gene showed up-regulation in 37.5% and down-regulation in 62.5% of the screened populations. Gene ontology of the differentially expressed genes from both parental and eighth generations of diamide-sprayed P. absoluta populations revealed three genes involved in the metabolic detoxification of diamides in P. absoluta. Therefore, our study showed that the detoxification enzymes found could be responsible for P. absoluta diamide-based resistance, while behavioural resistance, which is stimulus-dependent, could be attributed to P. absoluta avermectin resistance., (© 2024. The Author(s).)

This study presents a novel, eco-friendly composite adsorbent material designed for the magnetic solid-phase extraction of diamide insecticides from vegetable samples. The membrane, denoted as Fe-MMm, was incorporated with a cellulose framework embedded with Metal-Organic Frameworks (MOFs) and Multi-Walled Carbon Nanotubes (MWCNTs) magnetized with Fe 3 O 4 . This innovative material streamlined the conventional solid-phase extraction process, simplifying the sample pre-treatment. By combining it with liquid chromatography tandem mass spectrometry (LC-MS/MS), the method achieves significantly enhanced extraction efficiency through systematic optimization of experimental parameters, including adsorbent selection, pH, ionic strength, adsorption time, and elution time. The method had a wide linear range of 0.1-1000 ng/mL and an exceptionally low detection limit ranging from 0.023 to 0.035 ng/mL. The successful identification of diamide insecticides in vegetable samples underscores the potential of Fe-MMm as a robust material for sample pretreatment in analytical applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Efficiently detecting diamide insecticides in environmental water is challenging due to their low concentrations and complex matrix interferences. In this study, we developed ionic liquids (ILs)-incorporated magnetic molecularly imprinted polymers (IL-MMIPs) for the detection of diamide insecticides, capitalizing on the advantages of ILs and quick magnetic separation through surface imprinting. Tetrachlorantraniliprole was used as the template, and a specific IL, 1-vinyl-3-ethylimidazolium hexafluorophosphate ([VEIm][PF 6 ]), was employed as the functional monomer. Various synthesis conditions were investigated to optimize adsorption efficiency. The prepared IL-MMIPs were successfully employed as adsorbents in magnetic solid-phase extraction (MSPE) to selectively extract, separate, and quantify three types of diamide insecticides from water samples using HPLC-UV detection. Under optimal conditions, the analytical method achieved low limits of detection (0.69 ng mL -1 , 0.64 ng mL -1 , 0.59 ng mL -1 for cyantraniliprole, chlorantraniliprole and tetrachlorantraniliprole, respectively). The method also displayed a wide linear range (0.003-10 μg mL -1 for cyantraniliprole and chlorantraniliprole, and 0.004-10 μg mL -1 for tetrachlorantraniliprole, respectively) with satisfactory coefficients (R 2 ≥0.9996), and low relative standard deviation (RSD≤2.55%). Additionally, extraction recoveries fell within the range of 79.4%-109%. The results clearly demonstrate that IL-MMIPs exhibit exceptional recognition and rebinding capabilities. The developed IL-MMIPs-MSPE-HPLC-UV method is straightforward and rapid, making it suitable for the detection and analysis of three kinds of diamide insecticides in environmental water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A set of focused analogues have been generated around a lead indirect adenosine monophosphate-activated kinase (AMPK) activator to improve the rat clearance of the molecule. Analogues were focused on inhibiting amide hydrolysis by the strategic placement of substituents that increased the steric environment about the secondary amide bond between 4-aminopiperidine and pyridine-5-carboxylic acid. It was found that placing substituents at position 3 of the piperidine ring and position 4 of the pyridine could all improve clearance without significantly impacting on-target potency. Notably, trans -3-fluoropiperidine 32 reduced rat clearance from above liver blood flow to 19 mL/min/kg and improved the hERG profile by attenuating the basicity of the piperidine moiety. Oral dosing of 32 activated AMPK in mouse liver and after 2 weeks of dosing improved glucose handling in a db/db mouse model of Type II diabetes as well as lowering fasted glucose and insulin levels.

The nest-scavenging beetle Aethina tumida remains a persistent problem for beekeepers in parts of the Southeast United States, where warm wet soils allow beetle populations to grow rapidly and overwhelm colonies, especially during the summer dearth. Furthermore, small hive beetle infestation prevents beekeepers from easily provisioning colonies with additional pollen or protein feed (patties), preventing holistic management of honey bee health via improved nutrition, and reducing the economic potential of package and nucleus colony rearing in the Southeast. Here, we demonstrate using both in vitro laboratory trials and a small in vivo field trial that the differential specificity of anthranilic diamide insecticides (specifically, chlorantraniliprole) between bees and beetles allows for the control and prevention of small hive beetle infestation in honey bee colonies even when feeding with large patties. Honey bees show orders of magnitude higher tolerance to chlorantraniliprole compared to small hive beetles, opening new avenues for improving bee health including during spring splits and throughout the summer., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America.)

Diamide insecticides, such as chlorantraniliprole, have been widely used to control insect pests by targeting the insect ryanodine receptor (RyR). Due to the efficacious insecticidal activity of diamides, as well as an increasing number of resistance cases, the molecular structure of RyR has been studied in many economically important insects. However, no research has been conducted on diamide resistance and RyR in the soybean looper, Chrysodeixis includens, a significant crop pest. In this study, we found moderate resistance to chlorantraniliprole in a field population from Puerto Rico and sequenced the full-length cDNA of the C. includens RyR gene, which encodes a 5124 amino acid-long protein. Genomic analysis revealed that the CincRyR gene consists of 113 exons, one of the largest exon numbers reported for RyR. Alternative splicing sites were detected in the cytosolic region. The protein sequence showed high similarity to other noctuid RyRs. Conserved structural features included the selectivity filter motif critical for ryanodine binding and ion conduction, as well as various domains involved in ion transport. Two mutation sites associated with diamide resistance in other insects were screened but not found in the Puerto Rico field populations or in the susceptible lab strain. Gene expression analysis indicated high expression of RyR in the third instar larval stage, particularly in muscle-containing tissues. Furthermore, exposure to a sublethal dose of chlorantraniliprole reduced RyR expression levels after 96 h. This study provides a molecular basis for understanding RyR structure and sheds light on potential mechanisms of diamide resistance in C. includens., (© 2023 Wiley Periodicals LLC.)

Since 2007, diamide insecticides have been widely used in Korea to control various types of lepidopteran pests including Spodoptera exigua. For nearly a decade, diamide resistance in field populations of S. exigua across 18 localities has been monitored using bioassays. Despite their short history of use, resistance to diamide insecticides has emerged. Based on the LC 50 values, some field populations showed a higher level of resistance to chlorantraniliprole, a diamide insecticide, compared to that of the susceptible strain, although regional and temporal variations were observed. To investigate resistance at a molecular level, we examined three mutations (Y4701C, I4790M, and G4946E) in the ryanodine receptor (RyR), which is the primary mechanism underlying diamide insecticide resistance. DNA sequencing showed that only the I4790M mutation was found in most field populations. As resistance levels varied significantly despite the uniform presence of the I4790M mutation, we considered the presence of another resistance factor. Further, the I4790M mutation was also found in S. exigua specimens collected prior to the commercialization of diamide insecticides in Korea as well as in other countries, such as the USA. This finding led us to hypothesize that the I4790M mutation were predisposed in field populations owing to selection factors other than diamide use. For further clarification, we conducted whole-genome sequencing of S. exigua (449.83 Mb) and re-sequencing of 18 individual whole genomes. However, no additional non-synonymous mutations were detected in the RyR-coding region. Therefore, we concluded that the high level of diamide insecticide resistance in Korean S. exigua is not caused by mutations at the target site, RyR, but is attributed to other factors that need to be investigated in future studies. [Display omitted] • The I4790M mutation in the RyR gene was identified in field populations of S. exigua before the introduction of commercial diamide insecticides. • No other non-synonymous mutations were detected in the RyR coding sequences obtained from whole genome re-sequencing. • It is possible that alternative mechanisms, rather than the I4790M mutation, are primarily responsible for diamide resistance in S. exigua. [ABSTRACT FROM AUTHOR]

• Two novel cyclohexyl o-oxydiamides(R-CDA) ligands with different alkyl chain were synthesized. • Their coordination behavior with lanthanide elements has been studied. • Both 1:1 and 1:2 metal/ligand complexes can formed during extraction, in which 1:2 complexes are more stable. • The higher stability of straight chain ligand complexes may be related to the higher coordination numbers. • The coordination through the C O and C O C bonds in the ligands, in which C O bond combindes more tightly. In this work, two cyclohexyl o-oxydiamides ligands: 2,2′-(cyclohexane-1,2-diylbis(oxy))bis(N,N-dioctylacetamide)(L1 : Octy-CDA) and 2,2′-(cyclohexane-1,2-diylbis(oxy))bis(N,N-bis(2-ethylhexyl)acetamide) (L2 : 2-ethylhexyl-CDA) have been synthesized to study the extraction and coordination behaviors with trivalent lanthanides in HNO 3 media. The extractability of ligands increases with the atomic number of lanthanides increasing. The straight alkyl chain demonstrated better extraction ability than the branched chain, which was also most likely caused by the impact of steric hindrance effects. Coordination chemistry studies were evaluated through slope analysis, ultraviolet–visible spectroscopy, nuclear magnetic resonance spectroscopy, electrospray ionization mass spectrometry, Fourier transform infrared spectroscopy and fluorescence, and all the results indicating that lanthanides with the above ligands can form both 1:1 and 1:2 metal/ligand complexes during extraction, and two ligands are tetradentate ligands. Density functional theory (DFT) calculations shed light that the interaction between the carbonyl oxygen atom and Eu(III) in the ligand is much stronger than that of the ether-bonded oxygen atom, and the analysis of the bond-forming properties shows that the stability of the 1:2 complex is stronger than that of the 1:1 complex. This work enriched the coordination study of diamide with lanthanides, which is expected to improve our understanding of the chemical properties of lanthanides during coordination and provide new insight into the design and synthesis of novel ligands. [ABSTRACT FROM AUTHOR]