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Most spectral–spatial classification methods for hyperspectral images (HSIs) can achieve satisfactory classification results. However, the common problem faced with these approaches is the need for a long training time and sufficient training samples. To address this issue, this study proposes an effective spectral–spatial HSI classification method based on superpixel merging, superpixel smoothing and broad learning system (SMS‐BLS). The newly introduced parameter‐free superpixel merging technique based on local modularity not only enhances the role of local spatial information in classification, but also maintains class boundary information as much as possible. In addition, the spectral and spatial information of HSIs is further fused during the superpixel smoothing process. As a result, with limited training samples, using merged and smoothed superpixels instead of pixels as input to the broad learning system significantly improves its classification performance. Moreover, the merged superpixels weaken the dependence of the classification results on the superpixel segmentation scale. The effectiveness of the proposed method was validated on three HSI benchmarks, namely Indian Pines, Pavia University and Salinas. Experimental and comparative results show the superiority of the method to other state‐of‐the‐art approaches in terms of overall accuracy and running time. [ABSTRACT FROM AUTHOR]

Adaptive evolution following colonization can affect the impact of invasive species. The fall webworm (FWW) invaded China 40 years ago through a single introduction event involving a severe bottleneck and subsequently diverged into two genetic groups. The well‐recorded invasion history of FWW, coupled with a clear pattern of genetic divergence, provides an opportunity to investigate whether there is any sign of adaptive evolution following the invasion. Based on genome‐wide SNPs, we identified genetically separated western and eastern groups of FWW and correlated spatial variation in SNPs with geographical and climatic factors. Geographical factors explained a similar proportion of the genetic variation across all populations compared with climatic factors. However, when the two population groups were analysed separately, environmental factors explained more variation than geographical factors. SNP outliers in populations of the western group had relatively stronger response to precipitation than temperature‐related variables. Functional annotation of SNP outliers identified genes associated with insect cuticle protein potentially related to desiccation adaptation in the western group and genes associated with lipase biosynthesis potentially related to temperature adaptation in the eastern group. Our study suggests that invasive species may maintain the evolutionary potential to adapt to heterogeneous environments despite a single invasion event. The molecular data suggest that quantitative trait comparisons across environments would be worthwhile. [ABSTRACT FROM AUTHOR]

Background: Several agricultural fungicides are known to affect insect pests directly and these effects may be transgenerational and mediated through impacts on endosymbionts, providing opportunities for pest control. The cotton aphid Aphis gossypii is a polyphagous pest that can cause large crop yield losses. Here, we tested the effects of three fungicides, pyraclostrobin, trifloxystrobin and chlorothalonil, on the fitness and Buchnera endosymbiont of A. gossypii. Results: The formulations of trifloxystrobin and pyraclostrobin, and the active ingredient of pyraclostrobin produced dose‐dependent mortality in A. gossypii, whereas there was no dose‐dependent mortality for chlorothalonil. The formulations of trifloxystrobin and pyraclostrobin significantly reduced the lifespan and fecundity of A. gossypii, and increased the density of Buchnera in the parental generation but not the (unexposed) F1. When the active ingredient of pyraclostrobin was tested, the lifespan of the F0 generation was also reduced, but the density of Buchnera was not, indicating that non‐insecticidal chemicals in the fungicide formulation may affect the density of the endosymbiont of A. gossypii. There was no transgenerational effect of the active ingredient of pyraclostrobin on the lifespan and Buchnera of (unexposed) F1. Conclusions: Our results suggest that formulations of two strobilurin fungicides have immediate impacts on the fitness of A. gossypii, and chemicals in the formulation impact the density of the primary Buchnera endosymbiont. Our study highlights the potential effects of non‐insecticidal chemicals of fungicides on aphid pests and their primary endosymbionts but direct connections between fitness and Buchnera densities remain unclear. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Field control of pest thrips mainly relies on insecticides, but the toxicity of insecticides can vary among thrips species and populations. In this study, we examined the susceptibility of multiple field populations of two thrips pests, Frankliniella occidentalis, and Thrips palmi, that often co‐occur on vegetables, to nine insecticides belonging to seven subgroups. RESULTS: The highest level of variation in susceptibility among F. occidentalis populations was for spinetoram (73.92 fold difference between most resistant and most susceptible population), followed by three neonicotinoids (8.06–15.99 fold), while among T. palmi populations, it was also for spinetoram (257.19 fold), followed by emamectin benzoate, sulfoxaflor, and acetamiprid (23.64–45.50 fold). These findings suggest evolved resistance to these insecticides in some populations of the two thrips. One population of F. occidentalis had a particularly high level of resistance overall, being the most resistant for five of the nine insecticides tested. Likewise, a population of T. palmi had high resistance to all nine insecticides, again suggesting the evolution of resistance to multiple chemicals. For F. occidentalis, the LC95 values of most populations were higher than the field‐recommended dosage for all insecticides except chlorfenapyr and emamectin benzoate. For several T. palmi populations, the LC95 values also tended to be higher than recommended dosages, except in the case of emamectin benzoate and spinetoram. CONCLUSIONS: Our study found interspecific and intraspecific variations in the susceptibility of two thrips to nine insecticides and multiple resistance in some populations, highlighting the need for ongoing monitoring and resistance management. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pesticide resistance is a long‐standing and growing problem in the chemical control of invertebrate pests. Molecular diagnostic methods can facilitate pesticide resistance management by accurately and efficiently detecting resistant mutations and their frequency. In this study, the kompetitive allele specific PCR (KASP) approach, a technology for high‐throughput single nucleotide polymorphism (SNP) genotyping, is validated as a useful method for characterizing genotypes at a pesticide‐resistance locus for the first time. We focus on the spinetoram resistance mutation of G275E in the nicotinic acetylcholine receptor alpha 6 (nAChR α6) subunit gene of Thrips palmi. RESULTS: Of the 341 individuals of Thrips palmi tested, 98.24% were successfully genotyped, with 100% concordance with Sanger sequencing results. We then quantitatively mixed genomic DNA of known genotypes to establish 21 DNA mixtures with a resistant allele frequency ranging from 0 to 100% at steps of 5%. The linear discriminant analysis (LDA) showed that 75.8% of original grouped cases were correctly classified; six groups had no overlap in membership (resistant allele frequency: 0%, 5%, 10–75%, 80–85%, 90–95%, and 100%). When we chose 11 pooled samples with 10% steps for LDA, 84.4% of original grouped cases were correctly classified; seven groups had no overlap in membership (0%, 10%, 20–30%, 40–70%, 80%, 90%, 100%). The results indicated that KASP applied to pooled samples may provide a semi‐quantitative estimate of resistance. CONCLUSIONS: Our study points to the suitability of KASP for high‐throughput genotyping of genotypes affecting pesticide resistance and semi‐quantitative assessments of resistance allele frequencies in populations. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: The two‐spotted spider mite (TSSM), Tetranychus urticae (Acari: Tetranychidae), is a cosmopolitan phytophagous pest in agriculture and horticulture. It has developed resistance to many acaricides by target‐site mutations. Understanding the status and evolution of resistant mutations in the field is essential for resistance management. Here, we applied a high‐throughput Kompetitive allele‐specific polymerase chain reaction (KASP) method for detecting six mutations conferring resistance to four acaricides of the TSSM. We genotyped 3274 female adults of TSSM from 43 populations collected across China in 2017, 2020, and 2021. Results: The KASP genotyping of 24 testing individuals showed 99% agreement with Sanger sequencing results. KASP assays showed that most populations had a high frequency of mutations conferring avermectin (G314D and G326E) and pyridaben (H92R) resistance. The frequency of mutation conferring bifenazate (A269V and G126S) and etoxazole (I1017F) resistance was relatively low. Multiple mutations were common in the TSSM, with 70.2% and 24.6% of individuals having 2–6 and 7–10 of 10 possible resistant alleles, respectively. No loci were linked in most populations among the six mutations, indicating the development of multiple resistance is mainly by independent selection. However, G314D and I1017F on the nuclear genome deviated from Hardy–Weinberg equilibrium in most populations, indicating significant selective pressure on TSSM populations by acaricides or fitness cost of the mutations in the absence of acaricide selection. Conclusion: Our study revealed that the high frequency of TSSMs evolved multiple resistant mutations in population and individual levels by independent selection across China, alarming for managing multiple‐acaricides resistance. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Laser technology has been widely used in the treatment of hypertrophic scar (HPS). Due to the lack of effective quantitative relationship between laser doses and thermal effect of lesion tissue, the selection of laser doses in clinical laser treatment of HPS is blind, which cannot guarantee the best treatment effect. Materials and methods: The photothermal model of HPS was established by using finite element method. The effects of laser dose parameters such as laser energy density, pulse width, and spot diameter on the thermal effects of laser treatment were analyzed. According to tissue temperature threshold and thermal damage degree of the simulation results, the optimal laser doses of HPS were selected for the laser treatment experiments of rabbit ear HPSs to verify the rationality of the quantitative photothermal model. Results: The temperature rise and thermal damage degree of HPS following laser treatment were directly correlated to the laser doses, which grew with the increase of energy density and laser pulse width. For the different spot diameters, the temperature rise decreased with the increase of spot diameter, whereas the thermal damage degree worsened with the increase of spot diameter. Both simulation and experimental results show that the optimal treatment parameters of HPS were as follows: The laser energy density was 7.5 J/cm3, the pulse width was 4 ms, and the spot diameter was 7 mm. Conclusion: The laser dose parameters optimized by the photothermal model have achieved good therapeutic effects in the rabbit ear HPS, indicating that the model can be used for quantitative evaluation of laser doses before clinical treatment. [ABSTRACT FROM AUTHOR]

BACKGROUND: The diamondback moth (DBM) Plutella xylostella has developed resistance to almost all insecticides used to control it. Populations of DBM in temperate regions mainly migrate from annual breeding areas. However, the distribution pattern of insecticide resistance of DBM within the context of long-distance migration remains unclear. RESULTS: In this study, we examined the frequency of 14 resistance mutations for 52 populations of DBM collected in 2010, 2011, 2017 and 2018 across China using a high-throughput KASP genotyping method. Mutations L1041F and T929I conferring pyrethroid resistance, and mutations G4946E and E1338D conferring chlorantraniliprole resistance were near fixation in most populations, whereas resistant alleles of F1020S, M918I, A309V and F1845Y were uncommon or absent in most populations. Resistance allele frequencies were relatively stable among different years, although the frequency of two mutations decreased. Principal component analysis based on resistant allele frequencies separated a southern population as an outlier, whereas the immigrants clustered with other populations, congruent with the migration pattern of northern immigrants coming from the Sichuan area of southwestern China. Most resistant mutations deviated from Hardy–Weinberg equilibrium due to a lower than expected frequency of heterozygotes. The deviation index of heterozygosity for resistant alleles was significantly higher than the index obtained from single nucleotide polymorphisms across the genome. These findings suggest heterogeneous selection pressures on resistant mutations. CONCLUSION: Our results provide a picture of resistant mutation patterns in DBM shaped by insecticide usage and migration of this pest, and highlight the widespread distribution of resistance alleles in DBM. [ABSTRACT FROM AUTHOR]

Background: Thrips pests cause increasing damage to crops around the world. Widespread usage of some insecticides against thrips has now led to the evolution of resistance to several active ingredients, and new insecticides are required. This study examined the toxicity of the novel insecticide broflanilide to multiple populations of several thrips pests. Results: Bioassays showed that thrips populations had LC50 values ranging from 0.5 to almost 300 mg·L−1. A population of Frankliniella occidentalis had the highest LC50 value at 290.63 mg·L−1, while a population of Echinothrips americanus had the lowest LC50 value at 0.51 mg L−1. LC50 values among seven populations of Thrips palmi ranged from 2.5689 to 23.6754 mg·L−1, indicating intraspecific variation in toxicity. In this species, the toxicity of broflanilide was relatively higher in adults than in larvae. More than 90% of eggs of T. palmi could not develop into larvae when treated with 5–50 mg L−1 broflanilide. Compared to five commonly used insecticides, broflanilide showed relatively high toxicity to T. palmi. Field control tests with T. palmi showed that control efficacy (from 90.44% to 93.14%) was maintained from day three to day 14 after treatment with 22.5 and 45 ga.i hm−1 broflanilide. Conclusion: Broflanilide is potentially a useful insecticide for controlling Thrips hawaiiensis, Frankliniella intonsa, Megalurothrips usitatus. E. americanus, and some populations of T. palmi. However, the variation in toxicity of this insecticide to different species, populations, and developmental stages indicates that target species and life stages may need to be carefully considered. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Increasing damage of pests in agriculture and forestry can arise both as a consequence of changes in local species and through the introduction of alien species. In this study, we used population genetics approaches to examine population processes of two pests of the tree‐of‐heaven trunk weevil (TTW), Eucryptorrhynchus brandti (Harold) and the tree‐of‐heaven root weevil (TRW), E. scrobiculatus (Motschulsky) on the tree‐of‐heaven across their native range of China. We analyzed the population genetics of the two weevils based on ten highly polymorphic microsatellite markers. Population genetic diversity analysis showed strong population differentiation among populations of each species, with FST ranges from 0.0197 to 0.6650 and from −0.0724 to 0.6845, respectively. Populations from the same geographic areas can be divided into different genetic clusters, and the same genetic cluster contained populations from different geographic populations, pointing to dispersal of the weevils possibly being human‐mediated. Redundancy analysis showed that the independent effects of environment and geography could account for 93.94% and 29.70% of the explained genetic variance in TTW, and 41.90% and 55.73% of the explained genetic variance in TRW, respectively, indicating possible impacts of local climates on population genetic differentiation. Our study helps to uncover population genetic processes of these local pest species with relevance to control methods. [ABSTRACT FROM AUTHOR]

Invasive species pose increasing threats to global biodiversity and ecosystems. While previous studies have characterized successful invaders based on ecological traits, characteristics related to evolutionary processes have rarely been investigated. Here we compared gene flow and local adaptation using demographic analyses and outlier tests in two co‐occurring moth pests across their common native range of China, one of which (the peach fruit moth, Carposina sasakii) has maintained its native distribution, while the other (the oriental fruit moth, Grapholita molesta) has expanded its range globally during the past century. We found that both species showed a pattern of genetic differentiation and an evolutionary history consistent with a common southwestern origin and northward expansion in their native range. However, for the noninvasive species, genetic differentiation was closely aligned with the environment, and there was a relatively low level of gene flow, whereas in the invasive species, genetic differentiation was associated with geography. Genome scans indicated stronger patterns of climate‐associated loci in the noninvasive species. While strong local adaptation and reduced gene flow across its native range may have decreased the invasiveness of C. sasakii, this requires further validation with additional comparisons of invasive and noninvasive species across their native range. [ABSTRACT FROM AUTHOR]

Receptor activator of NF-κB ligand (RANKL) is essential for osteoclast formation and bone remodeling. Nevertheless, the cellular source of RANKL for osteoclastogenesis has not been fully uncovered. Different from peripheral adipose tissue, bone marrow (BM) adipose lineage cells originate from bone marrow mesenchymal stromal cells (BMSCs). Here, we demonstrate that adiponectin promoter-driven Cre expression (AdipoqCre) can target bone marrow adipose lineage cells. We cross the AdipoqCre mice with ranklfl/fl mice to conditionally delete RANKL from BM adipose lineage cells. Conditional deletion of RANKL increases cancellous bone mass of long bones in mice by reducing the formation of trabecular osteoclasts and inhibiting bone resorption but does not affect cortical bone thickness or resorption of calcified cartilage. AdipoqCre; ranklfl/fl mice exhibit resistance to estrogen deficiency and rosiglitazone (ROS)-induced trabecular bone loss but show bone loss induced by unloading. BM adipose lineage cells therefore represent an essential source of RANKL for the formation of trabecula osteoclasts and resorption of cancellous bone during remodeling under physiological and pathological conditions. Targeting bone marrow adiposity is a promising way of preventing pathological bone loss. [ABSTRACT FROM AUTHOR]

The peach fruit moth (PFM), Carposina sasakii Matsumura, is a major phytophagous orchard pest widely distributed across Northeast Asia. Here, we report the chromosome‐level genome for the PFM, representing the first genome for the family Carposinidae, from the lepidopteran superfamily Copromorphoidea. The genome was assembled into 404.83 Mb sequences using PacBio long‐read and Illumina short‐read sequences, including 275 contigs, with a contig N50 length of 2.62 Mb. All contigs were assembled into 31 linkage groups assisted by the Hi‐C technique, including 30 autosomes and a Z chromosome. BUSCO analysis showed that 98.3% of genes were complete and 0.4% of genes were fragmented, while 1.3% of genes were missing in the assembled genome. In total, 21,697 protein‐coding genes were predicted, of which 84.80% were functionally annotated. Because of the importance of diapause triggered by photoperiod in PFM, five circadian genes in the PFM as well as in the other related species were annotated, and potential genes related to diapause and photoperiodic reaction were also identified from transcriptome sequencing. In addition, manual annotation of detoxification gene families was undertaken and showed a higher number of glutathione S‐transferase (GST) gene in PFM than in most other lepidopterans, in contrast to a lower number of uridine diphosphate (UDP)‐glycosyltransferase (UGT) gene, carboxyl/cholinesterases (CCE) gene and cytochrome P450 monooxygenase (P450) gene, suggesting different detoxication pathways in this moth. The high‐quality genome provides a resource for comparative evolutionary studies of this moth and its relatives within the context of radiations across Lepidoptera. [ABSTRACT FROM AUTHOR]

BACKGROUND: The diamondback moth (DBM), Plutella xylostella (Lepidoptera: Plutellidae), is a notorious pest of cruciferous plants. In temperate areas, annual populations of DBM originate from adult migrants. However, the source populations and migration trajectories of immigrants remain unclear. Here, we investigated migration trajectories of DBM in China using genome-wide single nucleotide polymorphisms (SNPs) genotyped using double-digest RAD (ddRAD) sequencing. We first analyzed patterns of spatial and temporal genetic structure among southern source and northern recipient populations, then inferred migration trajectories into northern regions using discriminant analysis of principal components (DAPC), assignment tests, and spatial kinship patterns. RESULTS: Temporal genetic differentiation among populations was low, indicating that sources of recipient populations and migration trajectories are stable. Spatial genetic structure indicated three genetic clusters in the southern source populations. Assignment tests linked northern populations to the Sichuan cluster, and central–eastern populations to the southern and Yunnan clusters, indicating that Sichuan populations are sources of northern immigrants and southern and Yunnan populations are sources of central–eastern populations. First-order (full-sib) and second-order (half-sib) kin pairs were always found within populations, but ∼ 35–40% of third-order (cousin) pairs were found in different populations. Closely related individuals in different populations were found at distances of 900–1500 km in ∼ 35–40% of cases, while some were separated by > 2000 km. CONCLUSION: This study unravels seasonal migration patterns in the DBM. We demonstrate how careful sampling and population genomic analyses can be combined to help understand cryptic migration patterns in insects. [ABSTRACT FROM AUTHOR]

The melon thrips, Thrips palmi, is an increasingly important pest of vegetables in northern China. Some populations have developed resistance in the field to the insecticide spinetoram. Understanding the origin and dispersal of insecticide‐resistant populations can shed light on resistance management strategies. In this study, we tested susceptibility of seven greenhouse populations of T. palmi to spinetoram collected from a small area of about 300 km2 in Shandong Province and examined population genetic structure across the area based on a segment of mitochondrial cox1 gene and 22 microsatellite loci to infer the possible origin and dispersal of insecticide resistance. Levels of resistance to spinetoram differed among seven populations, which included one population with high resistance (LC50 = 759.34 mg/L), three populations with medium resistance (LC50 ranged from 28.69 to 34.79 mg/L), and three populations with low resistance (LC50 ranged from 7.61 to 8.97 mg/L). The populations were genetically differentiated into two groups unrelated to both levels of resistance and geographic distance. The molecular data indicated high levels of gene flow between populations with different levels of resistance to spinetoram and low gene flow among populations with the same level of resistance, pointing to a likely separate history of resistance evolution. Resistance levels of two tested populations to spinetoram decreased 23 and 4.6 times after five generations without any exposure to the pesticide. We therefore suspect that resistance of T. palmi most likely evolved in response to local applications of the insecticide. Our study suggests that the development of resistance could be avoided or resistance even reversed by reducing usage of spinetoram. [ABSTRACT FROM AUTHOR]

Thrips are tiny insects from the order Thysanoptera (Hexapoda: Condylognatha), including many sap‐sucking pests that are causing increasing damage to crops worldwide. In contrast to their closest relatives of Hemiptera (Hexapoda: Condylognatha), including numerous sap‐sucking species, there are few genomic resources available for thrips. In this study, we assembled the first thrips genome at the chromosomal level from the melon thrips, Thrips palmi, a notorious pest in agriculture, using PacBio long‐read and Illumina short‐read sequences. The assembled genome was 237.85 Mb in size, with 1,324 contigs and a contig N50 of 567 kb. All contigs were assembled into 16 linkage groups assisted by the Hi‐C technique. In total, 16,333 protein‐coding genes were predicted, of which 88.13% were functionally annotated. Among sap‐sucking insects, polyphagous species (e.g., T. palmi and Bemisia tabaci) usually possess more detoxification genes than oligophagous species (e.g., Diaphorina citri). The polyphagous thrips genomes characterized so far have relatively more detoxification genes in the GST and CCE families than polyphagous aphids, but they have fewer UGTs. HSP genes, especially from the Hsp70s group, have expanded in thrips compared to other hemipterans. These differences point to different genetic mechanisms associated with detoxification and stress responses in these two groups of sap‐sucking insects. The expansion of these gene families may contribute to the rapid development of pesticide resistance in thrips, as supported by a transcriptome comparison of resistant and sensitive populations of T. palmi. The high‐quality genome developed here provides an invaluable resource for understanding the ecology, genetics, and evolution of thrips as well as their relatives more generally. [ABSTRACT FROM AUTHOR]

Aim: A growing number of studies suggest that adaptation of invasive species plays key roles in their successful establishment in novel environments. However, adaptation of invasive species to climatic conditions remains poorly characterized. This study aimed to understand the population genetic structure produced by the cotton mealybug Phenacoccus solenopsis invasion and to identify preliminary signals of selection during its range expansion. Location: China. Methods: We examined genetic structure of 11 populations across China using SNPs, microsatellites and a segment of mitochondrial cox1 gene. ADMIXTURE, STRUCTURE and DAPC were used to infer population genetic structure; the dispersal routes were reconstructed by the DIYABC; SNPs potentially related to climate adaptation were identified by using four populations differentiation methods and three environmental association methods. Results: Strong genetic differentiation was found among populations with FST values ranging from 0.097 to 0.640 based on SNPs. Populations located at the northern expansion edge exhibited the highest genetic differentiation and the lowest genetic diversity. Demographic analyses indicated that all populations were introduced from a single source population with small effective size and low recent gene flow. RDA analysis showed that climatic variables explained a higher proportion of genetic variance (43%) compared to population structure variables (15%). The top climatic variables associated with genetic differentiation were precipitation of the mean temperature of warmest quarter, mean temperature of driest quarter and isothermality. Genes related to climate candidate SNPs were mainly enriched to pathways of development, energy and xenobiotic metabolisms. Main conclusions: We found that extremely rapid and strong population genetic differentiation among populations appears to have developed after introduction in the cotton mealybug. Our study points to rapid neutral evolution and suggests possible climatic adaptation despite low genetic diversity in this invasive species. [ABSTRACT FROM AUTHOR]

Biological invasions of pests into climatically unsuitable areas can be facilitated by human‐regulated environments, in which case there may be an impact on genetic structure through population processes and/or adaptation. Here, we investigated the population genetic structure of an invasive agricultural pest, Thrips palmi, in China, which has expanded its distribution range through using greenhouses. Early invaded populations showed a relatively higher level of genetic diversity than recently expanded greenhouse populations. Strong population genetic structure corresponded to a pattern of isolation by distance, with no recent gene flow and low historical gene flow among populations, reflecting limited ongoing dispersal. A genetic signature of population expansion was detected in early invaded populations and three northern populations from greenhouses, suggesting that the greenhouse environments facilitated expansion of this species. Redundancy analysis showed that the independent effects of environment and geography could explain 51.68% and 32.06% of the genetic variance, respectively. These findings point to climate‐ and greenhouse‐related spatial expansion, with the potential for adaptation by T. palmi. They emphasize the contribution of human‐regulated environments on the successes of this invasive species, a situation likely to apply to other invasive species that use greenhouse environments. [ABSTRACT FROM AUTHOR]

Pest species are often able to develop resistance to pesticides used to control them, depending on how rapidly resistance can emerge within a population or spread from another resistant population. We examined the evolution of bifenazate resistance in China in the two‐spotted spider mite (TSSM) Tetranychus uticae Koch (Acari: Tetranychidae), one of the most resistant arthropods, by using bioassays, detection of mutations in the target cytb gene, and population genetic structure analysis using microsatellite markers. Bioassays showed variable levels of resistance to bifenazate. The cytb mutation G126S, which confers medium resistance in TSSM to bifenazate, had previously been detected prior to the application of bifenazate and was now widespread, suggesting likely resistance evolution from standing genetic variation. G126S was detected in geographically distant populations across different genetic clusters, pointing to the independent origin of this mutation in different TSSM populations. A novel A269V mutation linked to a low‐level resistance was detected in two southern populations. Widespread resistance associated with a high frequency of the G126S allele was found in four populations from the Beijing area which were not genetically differentiated. In this case, a high level of gene flows likely accelerated the development of resistance within this local region, as well as into an outlying region distant from Beijing. These findings, therefore, suggest patterns consistent with both local evolution of pesticide resistance as well as an impact of migration, helping to inform resistance management strategies in TSSM. Pest species can often evolve resistance to pesticides used to control them. In this study, the authors found the independent origin of resistance mutation in different populations of the two‐spotted spider mite. A high level of gene flow likely accelerated the development of resistance within local region. These findings, therefore, suggest patterns consistent with both local evolution of pesticide resistance as well as an impact of migration, helping to inform resistance management strategies in two‐spotted spider mite. [ABSTRACT FROM AUTHOR]

The direct catalytic asymmetric aldol reaction is an emerging catalytic methodology that provides atom-economical access to functionalized chiral building blocks. Thioamides are useful aldol donors due to their high-fidelity chemoselective enolization and divergent post-aldol transformations. Herein we describe the incorporation of an α-vinyl appendage on a thioamide, which expands the utility of aldol adducts for natural product synthesis. This vinylated thioamide was not accommodated under the previously identified catalyst settings, but the newly developed catalytic conditions furnished aldol products containing the pendant vinyl group. [ABSTRACT FROM AUTHOR]

In this study, the problem of output regulation with passive performance control is investigated for a class of switched stochastic delay systems by using an average dwell time approach. It is assumed that the system under consideration is subject to the existence of time delays in both states and the regulators switching signal which causes asynchronous switching between candidate regulators and subsystems. By construction of a Lyapunov–Krasovskii (L–K) functional, sufficient conditions for the existence of the corresponding regulators are derived from the cases where the states are measurable and unmeasurable, respectively. Then, a switching signal is designed based on the upper bounds of the time delays. Finally, simulation examples are provided to illustrate the feasibility and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

BACKGROUND To understand the current status of insecticide resistance of the invasive western flower thrips, Frankliniella occidentalis, in China, the responses of six field populations to six commonly used insecticides, i.e. spinosad, spinetoram, cyantraniliprole, imidacloprid, acetamiprid and pyriproxyfen, were evaluated in comparison with a susceptible laboratory strain. RESULTS Field populations tended to be less susceptible than the laboratory strain. The population from Shouguang, Shandong Province, showed the lowest levels of susceptibility. A 15.64-fold and 17.29-fold resistance to spinosad and spinetoram was detected in the Shouguang population. A 11.74-fold and 13.64-fold resistance to cyantraniliprole was detected in populations from Daxing in the Beijing area and Shouguang. All populations showed a low level of resistance to imidacloprid, acetamiprid and pyriproxyfen, except for the Shouguang population, which was 127.58-fold more resistant to pyriproxyfen. CONCLUSION Variations in resistance to the tested insecticides were observed among the sampled population. Spinosad and spinetoram were the most efficient insecticides and are recommended for use in an integrated management programme. Resistance management strategies should be implemented to reduce the potential for resistance evolving. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Accurately quantifying cropland gross primary production ( GPP) is of great importance to monitor cropland status and carbon budgets. Satellite-based light-use efficiency ( LUE) models and process-based terrestrial biosphere models ( TBMs) have been widely used to quantify cropland GPP at different scales in past decades. However, model estimates of GPP are still subject to large uncertainties, especially for croplands. More recently, space-borne solar-induced chlorophyll fluorescence ( SIF) has shown the ability to monitor photosynthesis from space, providing new insights into actual photosynthesis monitoring. In this study, we examined the potential of SIF data to describe maize phenology and evaluated three GPP modeling approaches (space-borne SIF retrievals, a LUE-based vegetation photosynthesis model [ VPM], and a process-based soil canopy observation of photochemistry and energy flux [ SCOPE] model constrained by SIF) at a maize ( Zea mays L.) site in Mead, Nebraska, USA. The result shows that SIF captured the seasonal variations (particularly during the early and late growing season) of tower-derived GPP ( GPP_ EC) much better than did satellite-based vegetation indices (enhanced vegetation index [ EVI] and land surface water index [ LSWI]). Consequently, SIF was strongly correlated with GPP_ EC than were EVI and LSWI. Evaluation of GPP estimates against GPP_ EC during the growing season demonstrated that all three modeling approaches provided reasonable estimates of maize GPP, with Pearson's correlation coefficients ( r) of 0.97, 0.94, and 0.93 for the SCOPE, VPM, and SIF models, respectively. The SCOPE model provided the best simulation of maize GPP when SIF observations were incorporated through optimizing the key parameter of maximum carboxylation capacity ( Vcmax). Our results illustrate the potential of SIF data to offer an additional way to investigate the seasonality of photosynthetic activity, to constrain process-based models for improving GPP estimates, and to reasonably estimate GPP by integrating SIF and GPP_ EC data without dependency on climate inputs and satellite-based vegetation indices. [ABSTRACT FROM AUTHOR]

The title compound, C31H39NO, was prepared by the condensation of 5- tert-butyl-2-hydroxy-3-(1-phenylethyl)benzaldehyde with 2,6-diisopropylphenylamine in refluxing ethanol. The phenol ring and the phenylimino ring are approximately perpendicular, forming a dihedral angle of 81.5 (3)°. The phenyl ring makes a dihedral angle of 75.2 (2)° with the phenol ring and also makes a dihedral angle of 62.9 (3)° with the phenylimino ring. The molecular structure is stabilized by an intramolecular O—H...N hydrogen bond linking the phenol OH group and the phenylimino N atom. One of the isopropyl groups is disordered over two positions; the site occupancies are 0.55 and 0.45. [ABSTRACT FROM AUTHOR]

In the mol­ecule of the title compound, C18H20N4, the cyclo­hexane ring has a chair conformation. The dihedral angle between the two planar pyridine rings is 68.19 (3)°. [ABSTRACT FROM AUTHOR]