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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]

The South American tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a newly introduced invasive destructive pest that poses a major threat to tomato production in China. Chemical control is a predominantly measure for controlling this pest. Monitoring of insecticide efficacy is the basic tool for proactive evidence-based resistance management. As a new invasive species, the insecticide susceptibility of T. absoluta to main insecticides has been uncertainty so far in China. Here, we investigated the insecticide susceptibilities of seven populations (Yunnan, Guizhou, Sichuan, Gansu, Inner Mongolia, Shanxi and Xinjiang) of T. absoluta across China. The response of these populations was evaluated through laboratory bioassays with the main insecticides used for T. absoluta control: chlorantraniliprole, chlorpyrifos, indoxacarb, emamectin benzoate, spinosad and Bacillus thuringiensis. Analysis of the results showed the largest LC 50 values for chlorpyriphos were generated in populations from Shanxi and Yunnan, resulting in 22.59-fold and 11-fold differences, respectively, compared with the values generated in the most susceptible population (Inner Mongolia). The LC 50 values observed for chlorantraniliprole in Shanxi and Gansu were 24.66-fold and 20.83-fold greater, respectively, than the LC 50 value observed in the most susceptible population (Guizhou). However, almost all populations of T. absoluta presented low resistance levels to indoxacarb, emamectin benzoate, spinosad and B. thuringiensis. Our study sheds light on most insecticides can provide sufficient control of T. absoluta in China, however, scientific selection and use of insecticides, such as rotational use of insecticides of different modes of action classes, also need to adopt as soon as possible, because a moderate level of resistance has already been observed somewhere on chlorantraniliprole and chlorpyrifos. • Tuta absoluta is a newly introduced invasive destructive pest that poses a major threat to tomato production in China. • As a new invasive species, the susceptibilities of seven Chinese populations of T. absoluta collected from seven provinces to six types of insecticide were tested for the first time. • The results provides a foundation for designing management strategies to control and monitor this important pest in China. [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.

Staphylococcus aureus has to cope with oxidative and electrophile stress during host-pathogen interactions. The TetR-family repressor GbaA was shown to sense electrophiles, such as N-ethylmaleimide (NEM) via monothiol mechanisms of the two conserved Cys55 or Cys104 residues in vitro. In this study, we further investigated the regulation and function of the GbaA repressor and its Cys residues in S. aureus COL. The GbaA-controlled gbaAB-SACOL2595-97 and SACOL2592-nmrA-2590 operons were shown to respond only weakly 3-10-fold to oxidants, electrophiles or antibiotics in S. aureus COL, but are 57-734-fold derepressed in the gbaA deletion mutant, indicating that the physiological inducer is still unknown. Moreover, the gbaA mutant remained responsive to disulfide and electrophile stress, pointing to additional redox control mechanisms of both operons. Thiol-stress induction of the GbaA regulon was strongly diminished in both single Cys mutants, supporting that both Cys residues are required for redox-sensing in vivo. While GbaA and the single Cys mutants are reversible oxidized under diamide and allicin stress, these thiol switches did not affect the DNA binding activity. The repressor activity of GbaA could be only partially inhibited with NEM in vitro. Survival assays revealed that the gbaA mutant confers resistance under diamide, allicin, NEM and methylglyoxal stress, which was mediated by the SACOL2592-90 operon encoding for a putative glyoxalase and oxidoreductase. Altogether, our results support that the GbaA repressor functions in the defense against oxidative and electrophile stress in S. aureus. GbaA represents a 2-Cys-type redox sensor, which requires another redox-sensing regulator and an unknown thiol-reactive ligand for full derepression of the GbaA regulon genes. [Display omitted] • The TetR repressor GbaA is not fully inactivated by oxidants and electrophiles in S. aureus. • The GbaA regulon is induced by thiol stress in the gbaA mutant, indicating additional mechanisms of redox regulation. • Cys55 and Cys104 are both involved in redox-sensing of GbaA in S. aureus. • The GbaA regulon functions in the defense against diamide, allicin, NEM and methylglyoxal. [ABSTRACT FROM AUTHOR]

To understand the relationship between the structure and function of compounds for the extraction of Pd(II) from HCl solution, we investigated the Pd(II) extraction properties using three sulfide-containing diamides with the same N-substituents, N,Nʹ-dimethyl-N,Nʹ-diphenyl: thiodiglycolamide (mptdga), 3,3ʹ-thiodipropionamide (mptdpa), and 1,2-ethylene-bis(thioglycolamide) (mpebtga) diluted in chloroform. All of the diamides extract Pd(II) from 3.0 M HCl solution much faster than the conventional sulfide extractant, di-n-hexyl sulfide, and the extraction efficiency decreases in the order mpebtga > mptdpa > mptdga. The apparent stoichiometry of the Pd(II)−extractant complex extracted in the organic phase is 1:1 for mpebtga and 1:2 for mptdga and mptdpa. The FT-IR measurements show that the amide oxygen atoms in the diamides do not directly coordinate to Pd(II). These results indicate that the dominant complexes for the three diamides are [PdCl2(mptdga)2], [PdCl2(mptdpa)2], and [PdCl2(mpebtga)] with the sulfide coordinating to Pd(II). [ABSTRACT FROM AUTHOR]

The molecular structure of the title bis-pyridyl substituted diamide hydrate, C14H14N4O2·H2O, features a central C2N2O2 residue (r.m.s. deviation = 0.0205 Å) linked at each end to 3-pyridyl rings through methylene groups. The pyridyl rings lie to the same side of the plane, i.e. have a syn-periplanar relationship, and form dihedral angles of 59.71 (6) and 68.42 (6)° with the central plane. An almost orthogonal relationship between the pyridyl rings is indicated by the dihedral angle between them [87.86 (5)°]. Owing to an anti disposition between the carbonyl-O atoms in the core, two intramolecular amide-N—H...O(carbonyl) hydrogen bonds are formed, each closing an S(5) loop. Supramolecular tapes are formed in the crystal via amide-N—H...O(carbonyl) hydrogen bonds and ten-membered {...HNC2O}2 synthons. Two symmetry-related tapes are linked by a helical chain of hydrogen-bonded water molecules via water-O—H...N(pyridyl) hydrogen bonds. The resulting aggregate is parallel to the b-axis direction. Links between these, via methylene-C—H...O(water) and methylene-C—H...π(pyridyl) interactions, give rise to a layer parallel to (10\overline{1}); the layers stack without directional interactions between them. The analysis of the Hirshfeld surfaces point to the importance of the specified hydrogen-bonding interactions, and to the significant influence of the water molecule of crystallization upon the molecular packing. The analysis also indicates the contribution of methylene-C—H...O(carbonyl) and pyridyl-C—H...C(carbonyl) contacts to the stability of the inter-layer region. The calculated interaction energies are consistent with importance of significant electrostatic attractions in the crystal.

The tobacco budworm, Chloridea (Heliothis) virescens (F.), has evolved resistance to numerous insecticides in the field. In tobacco, chlorantraniliprole can be applied as either a preventative systemic soil application at or near transplant, or a foliar application timed to current treatment thresholds. With a novel mode of action chlorantraniliprole provides an option for rotation with other insecticides to reduce the probability of insecticide resistance development. However, specific usage patterns in tobacco have the potential to increase the risk of resistance development to this insecticide. In particular, soil applied treatments may expose C. virescens to sublethal concentrations of the insecticide. We studied chlorantraniliprole susceptibility in nine field populations and one laboratory strain of C. virescens using a diet incorporation bioassay. Mortality was measured at 7, 10, and 14 d after exposure. Our results demonstrated that bioassays should be evaluated at 14 d after exposure to optimize interpretation of the dose–response due to the antifeeding properties of chlorantraniliprole. We observed low variation within field-collected populations. Field populations were as susceptible as the laboratory strain; the resistance ratio at the 14-d evaluation for field-collected populations ranged from 1.01 to 1.05. A discriminating dose of 0.117, 0.080, and 0.070 μg a.i./g diet could be used at 7, 10, and 14 d, respectively. Larval growth varied between field populations. Two field populations continued growing on diet containing chlorantraniliprole and differed in size from the laboratory and other populations. Further evaluation of growth inhibition will be necessary. [ABSTRACT FROM AUTHOR]

The separation of lanthanides from trivalent actinides is a challenging topic at the back end of nuclear fuel cycle. Soft donor ligands have been proposed for the effective separation of lanthanide from trivalent actinides. However, many soft donor ligands are not found very effective while some others have shown great promise. In this connection, donor atom softness ligand stereochemistry, donor atom size, rigidity of rings, etc. have been quite important in deciding the selectivity. The present work deals with the density functional theoretical calculations on the complexation of Am3+ and Eu3+ with a series of tridentate diamide derivatives having the central coordinating atom as 'O', 'N' and 'S' with varying structural rigidity. The results indicated shorter 'M−N' and 'M−S' bond distances in the Am3+ complexes as compared to those in the respective Eu3+ complexes of the ligands where the structural rigidity is minimum. However, overall the selectivity is the combined effect of the interaction of two lateral amidic oxygen atoms and the central donor atom, which is significantly affected depending upon the structure of the ligands with same donor centres. Gibb's free energy values were calculated for the complexation with all the ligands which was used to predict the selectivity. One of the ligand having 'S' as the central donor atom found to be most selective for Am3+ over Eu3+. [ABSTRACT FROM AUTHOR]

The house fly, Musca domestica L. is an important mechanical vector of different pathogens of medical and veterinary importance. It is an organism well-known for its ability to develop insecticide resistance. In the current study, we investigated the genetic basis and mechanism of chlorantraniliprole resistance in a field strain of house fly by selecting it artificially in the laboratory with a commercial formulation of chlorantraniliprole (CTPR-SEL). After seven generations of consecutive selection with chlorantraniliprole, CTPR-SEL strain developed a 644-fold resistance compared with the Susceptible strain and a 3-fold resistance compared with the field strain. Reciprocal crossing between the CTPR-SEL and Susceptible homozygous strains revealed an autosomal and incomplete dominant mode of resistance to chlorantraniliprole. A direct test using a monogenic inheritance model based on chi-square analysis revealed that the resistance was governed by more than one gene. Bioassays with synergists indicated that esterases might be involved in the resistance of house fly to chlorantraniliprole. These findings may be helpful to the development of an improved strategy for chlorantraniliprole resistance management in house fly. [ABSTRACT FROM AUTHOR]

We investigated the efficacy of various insecticides, including diamide, on the oriental tea tortrix, Homona magnanima Diakonoff (Lepidoptera: Tortricidae), a major pest of tea (Camellia cinensis), in Kagoshima Prefecture, Japan. The results showed that diamide insecticides had low efficacy against the oriental tea tortrix in the southern part of the prefecture (Nansatsu region; Makurazaki City, Minamikyushu City). The LC50 values ranged from 28.26 to 267.62 ppm(Resistance Ratio(RR): 41.0–387.9)for flubendiamide, 40.60 to 67.75 ppm(RR: 24.9–41.6)for chlorantraniliprole, and 40.33 to 107.49 ppm (RR: 93.8–250.0) for cyantraniliprole, indicating that the oriental tea tortrix has developed resistance to diamide insecticides. The insecticides other than diamide and benzoylurea IGR were highly effective. However, in other areas of the prefecture, all insecticides(including diamide)tested showed high efficiency. Furthermore, crossbreeding experiments showed that diamide resistance is autosomal, incompletely recessive. In the future, it is necessary to monitor the recovery of susceptibility against diamide insecticides in the Nansatsu region while avoiding the expansion of resistance development. [ABSTRACT FROM AUTHOR]

The whitefly, Bemisia tabaci MEAM1 Gennadius causes serious losses to Florida vegetable and ornamental production. In 2019, a maximum dose bioassay was administered to 20 field populations of B. tabaci MEAM1 collected from various economic and weed hosts across south Florida to assess insecticide efficacy. The maximum dose bioassay tests the top labeled rate of the insecticide against B. tabaci adults on treated cotton leaves in a Petri dish over a 72-h period. A susceptible laboratory colony of B. tabaci MEAM1 and a colony of B. tabaci MED were also tested. Survival over 72 h was used to produce an area under the maximum dose curve, which was used to compare insecticide effects on different populations. Overall, imidacloprid demonstrated the poorest efficacy, dinotefuran and flupyradifurone were the most effective, and bifenthrin, cyantraniliprole, and thiamethoxam tended to group together, providing intermediate control. Across populations tested, survival in whitefly adults treated with dinotefuran was 50% lower than whiteflies treated with imidacloprid, about 33% lower than whiteflies treated with thiamethoxam, bifenthrin, and cyantraniliprole, and 10% lower than whiteflies treated with flupyradifurone. Efficacy of bifenthrin was less than imidacloprid on some populations, particularly from the Homestead area. Imidacloprid and thiamethoxam had no effect on mortality of the MED population when it was tested after 22 mo in culture without exposure to insecticides, although 7 mo later, these materials resulted in some mortality for the MED population. [ABSTRACT FROM AUTHOR]

Eukaryotic release factors 1 and 3, encoded by SUP45 and SUP35, respectively, in Saccharomyces cerevisiae, are required for translation termination. Recent studies have shown that, besides these two key factors, several genetic and epigenetic mechanisms modulate the efficiency of translation termination. These mechanisms, through modifying translation termination fidelity, were shown to affect various cellular processes, such as mRNA degradation, and in some cases could confer a beneficial phenotype to the cell. The most studied example of such a mechanism is [PSI+], the prion conformation of Sup35p, which can have pleiotropic effects on growth that vary among different yeast strains. However, genetic loci underlying such readthrough-dependent, background-specific phenotypes have yet to be identified. Here, we used sup35(C653R), a partial loss-of-function allele of the SUP35 previously shown to increase readthrough of stop codons and recapitulate some [PSI+]-dependent phenotypes, to study the genetic basis of phenotypes revealed by increased translational readthrough in two divergent yeast strains: BY4724 (a laboratory strain) and RM11_1a (a wine strain). We first identified growth conditions in which increased readthrough of stop codons by sup35(C653R) resulted in different growth responses between these two strains. We then used a recently developed linkage mapping technique, extreme QTL mapping (X-QTL), to identify readthrough-dependent loci for the observed growth differences. We further showed that variation in SKY1, an SR protein kinase, underlies a readthrough-dependent locus observed for growth on diamide and hydrogen peroxide. We found that the allelic state of SKY1 interacts with readthrough level and the genetic background to determine growth rate in these two conditions.

The extraction and recovery of uranium from low-concentration uranium-bearing liquids has practical and environmental value. The most efficient and economical method is adsorption. In this study, two novel adsorption materials were prepared by grafting malonamide and diglycolamide, functional groups with good chelating uranyl ions, onto the surface of chlorine spheres. The two materials showed good adsorption capacity of U(VI) from dilute solution with low acidity, up to 150 ± 0.5 mg/g and 47 ± 0.5 mg/g, respectively. The adsorption kinetics study showed that the adsorption process was chemical adsorption and endothermic. The adsorption material has a large particle size, is easy to use and recycle, and has good physical and chemical stability. [ABSTRACT FROM AUTHOR]

The whiA (NCgl1527) gene from Corynebacterium glutamicum plays a crucial role during cell growth, and WhiA is recognized as the transcription factor for genes involved in cell division. In this study, we assessed the regulatory role of the gene in cell physiology. Transcription of the gene was specifically downregulated by the thiol-specific oxidant, diamide, and by heat stress. Cells exposed to diamide showed decreased transcription of genes involved in cell division and these effects were more profound in Δ whiA cells. In addition, the Δ whiA cells showed sensitivity to thiol-specific oxidants, DNA-damaging agents, and high temperature. Further, downregulation of sigH (NCgl0733), the central regulator in stress responses, along with master regulatory genes in cell metabolism, was observed in the Δ whiA strain. Moreover, the amount of cAMP in the Δ whiA cells in the early stationary phase was only at 30% level of that for the wild-type strain. Collectively, our data indicate that the role of whiA is to downregulate genes associated with cell division in response to heat or thiol-specific oxidative stress, and may suggest a role for the gene in downshifting cell metabolism by downregulating global regulatory genes when growth condition is not optimal for cells. [ABSTRACT FROM AUTHOR]

BACKGROUND Pesticide resistance is a growing issue worldwide, and susceptibility of pest populations should be monitored in migratory intersection regions for successful resistance management. We determined the susceptibility of eight noctuid species from the Florida Panhandle to bifenthrin (pyrethroid) and chlorantraniliprole (diamide). Larvae from field and laboratory populations were exposed to commercial insecticide formulations using the leaf‐dip method in concentration–mortality bioassays. RESULTS: The field populations of Helicoverpa zea (Boddie), Spodoptera frugiperda (Smith), S. eridania (Stoll), S. exigua (Hubner) and Chloridea virescens (Fabricius) had reduced susceptibility to bifenthrin compared with the laboratory populations. Resistance ratios to bifenthrin were as high as 10 071‐fold in S. exigua and 436‐fold in S. frugiperda, while there was no reduced susceptibility in Agrotis ipsilon (Hufnagel). The susceptibility to chlorantraniliprole was similar between the field and laboratory populations studied, except for S. exigua that exhibited 630‐fold resistance to the diamide. The probit regression equations indicated that the larval mortality of S. exigua and S. frugiperda populations was <80% with bifenthrin at the concentration equivalent to the label rate. Likewise, the estimated mortality of S. exigua larvae with chlorantraniliprole at the label rate concentration was <80%. CONCLUSIONS: The lepidopteran pest populations tested were variable in susceptibility to bifenthrin by contrast to more consistent susceptibility to chlorantraniliprole. These results help in the choice of effective insecticides for integrated pest management and resistance management in cropping systems colonized by migratory lepidopteran pests from the U.S. Gulf Coast region. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A 4-yr study was conducted comparing the efficacy and value of fungicide-only (FST), neonicotinoid insecticide + fungicide (NST), and diamide insecticide + fungicide (DST) seed treatments for commercial corn Zea mays L. and soybean Glycines max (L.) Merr. production in Ontario, Canada. Plant stand, plant vigor, above- and below-ground insect injury, and yield were assessed on 160 field-scale experiments. Experiments also assessed early-season insect incidence and abundance using newly legislated thresholds for NST use in Ontario and in-season destructive sampling. Wireworms (Coleoptera: Elateridae) and white grubs (Coleoptera: Scarabeidae) were frequently observed at experimental sites; however, thresholds were rarely met and injury levels rarely led to yield loss. Of 129 and 31 corn and soybean sites, 8 and 6%, respectively, had a positive yield response to NST use. Across all sites, yield response of 0.1 and −0.05 Mg ha−1 was observed with NST use in corn and soybean, respectively; however, the costs associated with NST use were recovered at only 48 and 23% of corn and soybean sites, respectively, based on average grain prices and yields during the study. Infrequent incidence of economic injury and the absence of a consistent yield response to NST and DSTs throughout the 4 yr of the study indicate that widespread use of seed-applied insecticides in corn and soybean is unlikely to provide benefit to producers. These data highlight an opportunity for reducing input costs, environmental loading, and nontarget effects without adverse outcomes for Ontario producers. [ABSTRACT FROM AUTHOR]

This study examined changes in the proportions of ryanodine receptor mutations (G4946E and I4790K) for Plutella xylostella populations in the field. Results show that the proportion of G4946E decreased during the survey years without diamide application and that insects with I4790K were observed less frequently during the survey period. This study also examined the biotic performances of diamide-resistant P. xylostella strains. The results show that the diamide-resistant strains exhibited hatchability, larval development, and fecundity equivalent to those of diamide-susceptible strains. [ABSTRACT FROM AUTHOR]

[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.)