Development of an on-site diagnostic LAMP assay for rapid differentiation of the invasive pest Phthorimaea absoluta (Meyrick) using insect tissues.

BACKGROUND: The tomato leafminer, Phthorimaea absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a destructive invasive pest that originated in South America and has spread within China since 2017. A rapid method for on-site identification of P. absoluta is urgently needed for interception of this pest across China. RESULTS: We developed a loop-mediated isothermal amplification (LAMP) technique to differentiate P. absoluta from Liriomyza sativae, Chromatomyia horticola, and Phthorimaea operculella using extracted genomic DNA, which was then refined to create an on-site LAMP diagnostic method that can be performed under field conditions without the need for laboratory equipment. CONCLUSION: In the present research, we developed an on-site diagnostic method for rapid differentiation of P. absoluta from other insects with similar morphology or damage characteristics in China. © 2024 Society of Chemical Industry.

FgGmtB Plays an Important Role in Growth, Reproduction, Virulence and Deoxynivalenol Biosynthesis of Fusarium graminearum.

GDP-mannose transporters (GMTs) have been implicated in the virulence of some important pathogenic fungi, and guanosine diphosphate (GDP) mannose transporters transport GDP-mannose from the cytosol to the Golgi lumen prior to mannosylation, where mannose attaches to the modified protein. GMTs could be potential targets for new antifungal drugs, as disruption of any step in GDP-mannose biosynthesis can affect fungal viability, growth, or virulence. To date, the GDP-mannose transporter has been extensively studied in yeast, but its biological function in fungi, particularly F. graminearum, is still unclear. In this experimental study, the role of the GDP-mannose transporter in F. graminearum was investigated by analysing the VRG4 gene. FgGmtA and FgGmtB were blastp-derived from their Scvrg4 protein sequences and proved to be their functional homologues. The mutant and complementary strains of FgGmtA, FgGmtB and FgGmtA&B genes were generated and used to evaluate the effect of the two GMTs genes on mycelial growth, asexual reproduction, sexual reproduction, cell wall sensitivity, glyphosate synthesis and drug susceptibility. Only in the FgGmtB and FgGmtA&B mutants was the rate of mycelial growth slowed, conidium production increased, sexual reproduction impaired, cell wall sensitivity increased, glycemic content decreased, and drug sensitivity reduced. The results of the pathogenicity assessment of GMTs showed that only FgGmtB affects the patogenicity of F. graminearum. At the same time, the effect of GMTs on the ability of rhinoceros to synthesise DON toxins was investigated and the results showed that the ability of ΔFgGmtB and ΔFgGmtA&B mutants to produce the DON toxin was significantly reduced, and the expression of toxin-related genes was also reduced.

Life Table Parameters of the Tomato Leaf Miner Tuta absoluta (Lepidoptera: Gelechiidae) on Five Tomato Cultivars in China.

Tomato is the most preferred host plant for Tuta absoluta, a newly emerged devastating invasive pest in China. However, no study has evaluated the damage risk of T. absoluta on processed tomato worldwide. In the current study, the life table parameters of T. absoluta were systematically investigated on five tomato cultivars (one fresh tomato cultivar, four processed tomato cultivars) to determine their susceptibility to T. absoluta infestation. T. absoluta had a better population growth ability on the fresh tomato, "Dafen", showing shorter duration of the preadult stage, higher lifetime fecundity, and a higher intrinsic rate of increase compared to four processed tomato cultivars. Meanwhile, the life table parameters of T. absoluta among different processed tomato cultivars also showed significant differences. Th9 was the most susceptible to T. absoluta attack, while Th1902, Heinz1015, and Dimen2272 were the least suitable ones for its development and reproduction. In summary, these tomato cultivars are the most recommended for commercial tomato production to reduce the damage caused by T. absoluta and improve the integrated pest management strategy.

Opsin mutants alter host plant selection by color vision in the nocturnal invasive pest Tuta absoluta.

In insects, vision is crucial in finding host plants, but its role in nocturnal insects is largely unknown. Vision involves responses to specific spectra of photon wavelengths and opsins plays an important role in this process. Long-wavelength sensitive opsin (LW opsin) and blue-sensitive opsin (BL opsin) are main visual opsin proteins and play important in behavior regulation.We used CRISPR/Cas9 technology to mutate the long-wavelength-sensitive and blue wavelength-sensitive genes and explored the role of vision in the nocturnal invasive pest Tuta absoluta. Light wave experiments revealed that LW2(-/-) and BL(-/-) mutants showed abnormal wavelength tropism. Both LW2 and BL mutations affected the preference of T. absoluta for the green environment. Mutations in LW2 and BL are necessary to inhibit visual attraction. The elimination of LW2 and BL affected the preference of leaf moths for green plants, and mutations in both induced a preference in moths for white plants. Behavioral changes resulting from LW2(-/-) and BL(-/-) mutants were not affected by sense of smell, further supporting the regulatory role of vision in insect behavior. To the best of our knowledge, this is the first study to reveal that vision, not smell, plays an important role in the host-seeking behavior of nocturnal insects at night, of which LW2 and BL opsins are key regulatory factors. These study findings will drive the development of the "vision-ecology" theory.

Prevalence and risk factors of elder abuse in survivors of stroke: A cross-sectional study.

Background and Aims: The understanding of the prevalence and risk factors associated with elder abuse in stroke survivors is currently lacking. Therefore, the objective of this study is to ascertain the prevalence and potential risk factors of elder abuse in stroke survivors, while also examining its correlation with insomnia. Methods: In this cross-sectional study, a total of 485 stroke survivors aged 65 years and older, who received treatment at the Emergency department of Shunde Hospital, Southern Medical University, were subjected to face-to-face interviews using the questionnaire on elder abuse from the Third Survey on Chinese Women's Social Status. A logistic regression analysis was employed to examine the association between risk factors and elder abuse among stroke survivors. Results: 62.27% of the participants reported experiencing elder abuse, with 14.85% of them indicating suffering from more than two subtypes of abuse. Factors such as residing in nursing homes, lower income, and smoking were found to increase the likelihood of experiencing elder abuse and all four subtypes of abuse. Additionally, advancing age was associated with a higher risk of experiencing all four subtypes of abuse, although it did not affect the occurrence of overall abuse. It is worth noting that the self-reported prevalence of the four types of abuse by the elderly themselves was higher compared to the reports provided by caregivers. Conclusion: Elder abuse is prevalent among stroke survivors, especially those who are residing in nursing homes, with lower income, and smokers. Elder abuse significantly increased the prevalence of insomnia in stroke survivors. Further research is needed to better explore effective measures to reduce the prevalence of elder abuse of stroke survivors.

A two-stage intrusion detection method based on light gradient boosting machine and autoencoder.

Intrusion detection systems can detect potential attacks and raise alerts on time. However, dimensionality curses and zero-day attacks pose challenges to intrusion detection systems. From a data perspective, the dimensionality curse leads to the low efficiency of intrusion detection systems. From the attack perspective, the increasing number of zero-day attacks overwhelms the intrusion detection system. To address these problems, this paper proposes a novel detection framework based on light gradient boosting machine (LightGBM) and autoencoder. The recursive feature elimination (RFE) method is first used for dimensionality reduction in this framework. Then a focal loss (FL) function is introduced into the LightGBM classifier to boost the learning of difficult samples. Finally, a two-stage prediction step with LightGBM and autoencoder is performed. In the first stage, pre-decision is conducted with LightGBM. In the second stage, a residual is used to make a secondary decision for samples with a normal class. The experiments were performed on the NSL-KDD and UNSWNB15 datasets, and compared with the classical method. It was found that the proposed method is superior to other methods and reduces the time overhead. In addition, the existing advanced methods were also compared in this study, and the results show that the proposed method is above 90% for accuracy, recall, and F1 score on both datasets. It is further concluded that our method is valid when compared with other advanced techniques.

Krüppel-homologue 1 regulates the development of Tuta absoluta and its cascade regulation pattern in the juvenile hormone signalling pathway.

Tomato leaf miner, Tuta absoluta (Meyrick), is one of the most destructive quarantine pests globally. It has been confirmed that Krüppel-homologue 1 (kr-h1) plays a key role in the regulation of juvenile hormone (JH). However, it is unclear how kr-h1 regulates the synthesis of JH and its cascade regulation pattern in tomato leaf miner. Here, we obtained the six JH signalling genes (kr-h1, Methoprene-tolerant, Forkhead box O, Juvenile acid methyltransferase, Juvenile hormone esterase and Fatty acid synthase 2), and applied RNA interference to explore the role of kr-h1 and the seven genes (plus Vitellogenin) regulation relationship in T. absoluta. Bioinformatics analysis revealed the structural characteristics of kr-h1 protein and JH receptor Met, which contained eight C2H2 zinc finger structures and three typical domains of the bHLH-PAS family, respectively. The expression levels of Met and Vg were upregulated after RNAi of kr-h1 gene, while the gene levels of JHAMT and FAS2 were downregulated. Furthermore, topical application of JH analogue to second instar larvae could induce the expression of kr-h1 and inhibit the expression of Met. Our study reveals the mechanism by which kr-h1 regulates JH pathway genes, which could be applied to control the growth of tomato leaf miners.

Climate change has increased the global threats posed by three ragweeds (Ambrosia L.) in the Anthropocene.

Invasive alien plants (IAPs) substantially affect the native biodiversity, agriculture, industry, and human health worldwide. Ambrosia (ragweed) species, which are major IAPs globally, produce a significant impact on human health and the natural environment. In particular, invasion of A. artemisiifolia, A. psilostachya, and A. trifida in non-native continents is more extensive and severe than that of other species. Here, we used biomod2 ensemble model based on environmental and species occurrence data to predict the potential geographical distribution, overlapping geographical distribution areas, and the ecological niche dynamics of these three ragweeds and further explored the environmental variables shaping the observed patterns to assess the impact of these IAPs on the natural environment and public health. The ecological niche has shifted in the invasive area compared with that in the native area, which increased the invasion risk of three Ambrosia species during the invasion process in the world. The potential geographical distribution and overlapping geographical distribution areas of the three Ambrosia species are primarily distributed in Asia, North America, and Europe, and are expected to increase under four representative concentration pathways in the 2050s. The centers of potential geographical distributions of the three Ambrosia species showed a tendency to shift poleward from the current time to the 2050s. Bioclimatic variables and the human influence index were more significant in shaping these patterns than other factors. In brief, climate change has facilitated the expansion of the geographical distribution and overlapping geographical distribution areas of the three Ambrosia species. Ecomanagement and cross-country management strategies are warranted to mitigate the future effects of the expansion of these ragweed species worldwide in the Anthropocene on the natural environment and public health.

Alzheimer's disease and epilepsy: The top 100 cited papers.

Background: Alzheimer's disease (AD) is one of the common neurodegenerative diseases, which often coexists with epilepsy. It is very significant to study the treatment options and the relationship between AD and epilepsy. Aims: The purpose of this study was to analyze the top 100 cited papers about AD and epilepsy using bibliometrics, and to describe the current situation and predict research hot spots. Methods: Top 100 papers were obtained from the Web of Science Core Collection (WoSCC). The WoSCC was used to analyze the author, institution, country, title, keywords, abstract, citation, subject category, publication year, impact factor (IF), and other functions. SPSS25 software was used for statistical analysis and CiteSpace V.5.7.R2 was used to visualize the information through collaborative networks. Results: The number of publications gradually increased from 2000 to 2021. The total citation count for the top 100 papers ranged from 15 to 433(mean = 67.43). The largest number of papers were published in 2016 (n = 11). Meanwhile, USA (centrality: 0.93) and Columbia University (centrality: 0.06) were the most influential research country and institutions, respectively. The top contributing journals was Journal of Alzheimer's Disease (8%). The IF for journals ranged from 1.819 to 53.44. A network analysis of the author's keywords showed that "beta" (centrality: 0.39), "amyloid beta" (centrality: 0.29), "hyperexcitability" (centrality: 0.29) and "disease" (centrality: 0.29) had a high degree of centrality. Conclusion: AD and epilepsy have been intensively studied in the past few years. The relationships, mechanisms and treatment of AD and epilepsy will be subjects of active research hotpots in future. These findings provide valuable information for clinicians and scientists to identify new perspectives with potential collaborators and cooperative countries.

Nonreproductive effects are more important than reproductive effects in a host feeding parasitoid.

When female host feeding parasitoids encounter a potential host, they face a complicated trade-off between either laying an egg for investing in current reproduction or feeding on or killing the host for future reproduction. Few studies have measured these behavioral shift patterns in a given host-parasitoid association thus far. We systematically assessed the behavioral shifts and life history traits of a host feeding parasitoid, Necremnus tutae, on different instars of its host Tuta absoluta. N. tutae females, as idiobiont host feeding parasitoids, can act on the 1st-4th instar larvae of T. absoluta by either host feeding, parasitizing or host killing. Moreover, a significant behavioral shift was observed on different instar hosts. N. tutae preferred to feed on the young hosts (1st and 2nd instars), lay eggs on middle-aged hosts (3rd instars) and kill old hosts (4th instars) by ovipositor-mediated stinging. The offspring of N. tutae showed a significant female-biased sex ratio, with the number of instars of T. absoluta larvae that were parasitized increasing. Specifically, nonreproductive host mortality induced by host feeding and host killing accounted for high percentages of the total mortality (ranging from 70% on 3rd instar hosts to 88% on 1st instar and 4th instar hosts). We hypothesize that N. tutae could be not merely a parasitoid but also a predator. Our results shed light on the nonreproductive abilities of a host feeding parasitoid that should be given further attention, especially when evaluating the efficacy of parasitoids.

First Report on CRISPR/Cas9-Based Genome Editing in the Destructive Invasive Pest Tuta Absoluta (Meyrick) (Lepidoptera: Gelechiidae).

The tomato leaf miner Tuta absoluta (Meyrick) is one of the world's most destructive pests of tomato, and because of its severe economic impacts, as well as the development of pesticide resistance, the species has been intensively studied, especially in regard to the identification of targets for T. absoluta control. However, functional genomic studies of T. absoluta have been constrained by a lack of effective genetic tools. Therefore, the aim of the present study was to develop a CRISPR/Cas9 zygote microinjection protocol for generating heritable mutations in T. absoluta, using the ommochrome synthesis gene cinnabar as an easily evaluated target gene. The injection of fertilised eggs with Cas9 protein and four sgRNAs, which targeted cinnabar exon 3, resulted in a mutagenesis rate of 31.9% for eggs reaching adulthood, and cinnabar mutagenesis resulted in either red or mosaic eye colour phenotypes. As such, this study is the first to report a complete and detailed CRISPR/Cas9 workflow for the efficient genome editing of the globally important invasive pest T. absoluta. The application of this robust genome-editing tool to T. absoluta will greatly facilitate the discovery of suitable RNAi control targets and the subsequent development of novel control strategies.

Ecological Niche Shifts Affect the Potential Invasive Risk of Rapistrum rugosum (L.) All. in China.

Ecological niche is a key concept that links species distributions. Ecological niche shifts are expected to affect the potential invasive risk of alien species. Rapistrum rugosum is an invasive agricultural weed in many countries. Wild populations of R. rugosum have been recorded in China, representing a great threat to the regional crops. Based on distribution records from different regions and relevant environmental variables, the present study predicted the potential distribution and estimated the invasive risk of R. rugosum in China. Ecological niche shifts strongly affected the potential invasive risk of R. rugosum in China. The two most important variables were annual temperature range (Bio7) and mean temperature of the coldest quarter (Bio11). The total suitable habitat for the species covered an area of 287.53 × 104km2 and was mainly distributed in Southwest, Southeast, and Central China. Australia, Canada, Brazil, the United States, and Argentina accounted for over 90% of the inspection records of R. rugosum from Chinese entry ports during 2015-2018. The intercepted R. rugosum was frequently mixed in Glycine max (L.) Merr., Hordeum vulgare L., linseed, Triticum aestivum L., and Sorghum bicolor (L.) Moench. Moreover, 80% interceptions were recorded from Tianjin, Guangdong, Nanjing, and Chengdu customs. Climatic conditions do not limit the establishment capability of R. rugosum in China. Our results provide a theoretical reference for the development of monitoring and control measures for this invasive weed.

Chromatin-Remodelling ATPases ISWI and BRM Are Essential for Reproduction in the Destructive Pest Tuta absoluta.

The tomato leaf miner (Tuta absoluta) is one of the top 20 plant pests worldwide. We cloned and identified the chromatin-remodelling ATPase genes ISWI and BRM by RACE and bioinformatic analysis, respectively; used RT-qPCR to examine their expression patterns during different life cycle stages; and elucidated their roles in insect reproduction using double-stranded RNA injections. The full-length cDNA of TaISWI was 3428 bp and it encoded a 1025-aa polypeptide. The partial-length cDNA of TaBRM was 3457 bp and it encoded a 1030-aa polypeptide. TaISWI and TaBRM were upregulated at the egg stage. Injection of TaISWI or TaBRM dsRNA at the late pupa stage significantly inhibited adult ovary development and reduced fecundity, hatchability, and longevity in the adult females. To the best of our knowledge, the present study was the first to perform molecular characterisations of two chromatin-remodelling ATPase genes and clarify their roles in T. absoluta fecundity. Chromatin-remodelling ATPases are potential RNAi targets for the control of T. absoluta and other insect pests. The present study was also the first to demonstrate the feasibility of reproductive inhibitory RNAi as a putative approach for the suppression of T. absoluta and other Lepidopteran insect populations.

Similar Bacterial Communities among Different Populations of a Newly Emerging Invasive Species, Tuta absoluta (Meyrick).

Microorganisms in the guts of insects enhance the adaptability of their hosts with different lifestyles, or those that live in different habitats. Tuta absoluta is an invasive pest that is a serious threat to tomato production in China. It has quickly spread and colonized Xinjiang, Yunnan and other provinces and regions. We used Illumina HiSeq next generation sequencing of the 16S rRNA gene to study and analyze the composition and diversity of the gut microbiota of three geographical populations of T. absoluta. At the phylum level, the most common bacteria in T. absoluta across all three geographical populations were Proteobacteria and Firmicutes. An uncultured bacterium in the Enterobacteriaceae was the dominant bacterial genus in the T. absoluta gut microbiotas. There were no significant differences in alpha diversity metrics among the Spanish, Yunnan and Xinjiang populations. The structures of the gut microbiota of the three populations were similar based on PCoA and NMDS results. The results confirmed that the microbial structures of T. absoluta from different regions were similar.

Insights into pectin dominated enhancements for elimination of toxic Cd and dye coupled with ethanol production in desirable lignocelluloses.

Pectin is a minor wall polysaccharide with potential applications for bioproducts. Despite the application of specific plants and biomass-based sorbents for environmental remediation, little has been reported about characteristic roles of pectin. Using the natural rice mutant (Osfc16) treated with Cd, this study explored that pectin could predominately enhance Cd accumulation with lignocellulose, mainly due to remarkably raised uronic acids deposition. The Cd-treatment further reduced lignocellulose recalcitrance for significantly enhanced biomass saccharification and bioethanol production along with almost complete Cd release. Using all remaining fermentation rice residues that are of typical ribbon-structure and large surface, this study generated novel biosorbents by optimal chemical oxidation with the pectin extraction from citrus peels, and examined consistently raised Cd and methylene blue (MB) adsorption capacities. Therefore, this work has proposed a mechanism model about multiple pectin enrichment roles for Cd and MB removals in agricultural and industry locations with full lignocellulose utilization towards bioethanol production.

The complete mitochondrial genome of invasive insect Leptinotarsa decemlineata Say 1824 (Coleoptera: Chrysomelidae).

Leptinotarsa decemlineata Say 1824, an invasive and globally devastating beetle, inflicts great damage to potato crops worldwide. The complete mitogenome of L. decemlineata is described in this study. It is a 16,741 bp long circular DNA molecule with a high A + T content of 76.9%, containing a typical 37 gene pattern. All PCGs (protein-coding genes) initiate with typical ATN codons. Most PCGs use TAN as a stop codon, whereas ND4 and COX3 use the incomplete codon TA as the stop codon. The lengths of rrnL and rrnS genes are 1,337 bp and 811 bp, respectively. All 22 tRNAs ranged from 62 to 77 bp. Phylogenetic analysis of Chrysomelidae indicated that L. decemlineata clusteres with three other Chrysomelinae species, which is consistent with previous analyses.

Climate Change Increases the Expansion Risk of Helicoverpa zea in China According to Potential Geographical Distribution Estimation.

Helicoverpa zea, a well-documented and endemic pest throughout most of the Americas, affecting more than 100 species of host plants. It is a quarantine pest according to the Asia and Pacific Plant Protection Commission (APPPC) and the catalog of quarantine pests for plants imported to the People's Republic of China. Based on 1781 global distribution records of H. zea and eight bioclimatic variables, the potential geographical distributions (PGDs) of H. zea were predicted by using a calibrated MaxEnt model. The contribution rate of bioclimatic variables and the jackknife method were integrated to assess the significant variables governing the PGDs. The response curves of bioclimatic variables were quantitatively determined to predict the PGDs of H. zea under climate change. The results showed that: (1) four out of the eight variables contributed the most to the model performance, namely, mean diurnal range (bio2), precipitation seasonality (bio15), precipitation of the driest quarter (bio17) and precipitation of the warmest quarter (bio18); (2) PGDs of H. zea under the current climate covered 418.15 × 104 km2, and were large in China; and (3) future climate change will facilitate the expansion of PGDs for H. zea under shared socioeconomic pathways (SSP) 1-2.6, SSP2-4.5, and SSP5-8.5 in both the 2030s and 2050s. The conversion of unsuitable to low suitability habitat and moderately to high suitability habitat increased by 8.43% and 2.35%, respectively. From the present day to the 2030s, under SSP1-2.6, SSP2-4.5 and SSP5-8.5, the centroid of the suitable habitats of H. zea showed a general tendency to move eastward; from 2030s to the 2050s, under SSP1-2.6 and SSP5-8.5, it moved southward, and it moved slightly northward under SSP2-4.5. According to bioclimatic conditions, H. zea has a high capacity for colonization by introduced individuals in China. Customs ports should pay attention to host plants and containers of H. zea and should exchange information to strengthen plant quarantine and pest monitoring, thus enhancing target management.

Managing depression and anxiety in patients with epilepsy in eastern China: A survey of epilepsy health professionals in Zhejiang Province.

OBJECTIVE: We aimed to evaluate the assessment and management of epilepsy with anxiety and depression, and their clinical practice based on a survey. METHODS: A cross-sectional survey of epilepsy health professionals was undertaken in Zhejiang Province using the modified International League Against Epilepsy (ILAE) Psychology Task Force questionnaire. We recorded the characteristics of participants and the practice of screening, referral, and treatment for depression and anxiety disorders. A total of 146 participants joined in the survey, of which 76.0% were neurologists, and 69 participants were the member of the Zhejiang Association Against Epilepsy (ZAAE). RESULTS: This survey revealed that almost all participants (87.7%) agreed that screening for depression and anxiety in patients with epilepsy (PWEs) was very important; however, the frequency of screening was very low (41.1% of participants screened less than 10% of patients, and 34.2% participants screened between 10% and 30% of patients). A higher frequency of screening was reported in the member group and compared with that in the non-member group (P = 0.025). The main barrier to screening was the lack of time during clinic visits: 81.5% participants included screening questions as part of their clinical review. When anxiety/depression was diagnosed, the next step should be to refer patients to a psychiatrist (78.1%). No standardized procedures and lack of mental health specialists trained to assess and/or manage PWEs, were the main barriers to follow-up assessment and management. Lack of appropriately trained mental health specialists was also the main barrier to psychological treatment for depression and anxiety. CONCLUSION: This survey highlighted that epilepsy healthcare professionals in Zhejiang province agreed on the importance of screening for psychiatric comorbidities in PWEs; however, the screening and management were actually insufficient. Certain barriers to screening, referral, and treatment were presented and improvements were recommended.

Screening Potential Reference Genes in Tuta absoluta with Real-Time Quantitative PCR Analysis under Different Experimental Conditions.

Tuta absoluta is one of the most significant invasive pests affecting tomato plants worldwide. RT-qPCR has emerged as one of the most sensitive and accurate methods for detecting gene expression data. The screening of stable internal reference genes is the most critical step for studying the molecular mechanisms of environmental adaptability. The stable reference genes expressed in T. absoluta under specific experimental conditions have not yet been clarified. In this study, seven candidate reference genes (RPL27, RPS13, RPS15, EF1-α, TUB, TBP, and ß-actin) and their optimal numbers were evaluated under biotic (developmental stages and adult tissues) and abiotic (insecticide, temperature, and plant VOC) conditions using four software programs. Our results identified the following reference genes and numbers as optimal: three genes (EF1-α, RPS13, and RPL27) for different developmental stages (egg, larva, pupa, unmated adult), two genes (RPS13 and TBP) for adult tissues (antenna, head, thorax, abdomen, leg), two genes (TBP and RPS13) for insecticides (Bacillus thuringiensis, chlorpyrifos, abamectin-aminomethyl, and chlorantraniliprole), two genes (RPL27 and TUB) for temperature-induced stresses (0, 25, and 40 °C), and two genes (RPS13 and TUB) for VOC-induced stresses (nonanal, α-phellandrene, and tomato leaves). Our results provide a reference for selecting appropriate reference genes for further study of the functional genes of T. absoluta under different experimental conditions.

Outbreak of the South American tomato leafminer, Tuta absoluta, in the Chinese mainland: geographic and potential host range expansion.

BACKGROUND: In 2017 Tuta absoluta was identified as an invasive species in China. Due to its rapid geographic expansion and the severe crop damage it causes, T. absoluta poses a serious threat to China's tomato production industry. To determine its geographic distribution and host range, intensive surveys and routine monitoring were conducted across the Chinese mainland between 2018 and 2019. The population colonization coefficient (PCC; ratio of colonized sites and prefectures) and population occurrence index (POI; ratio of infested host species and PCCs) were calculated. RESULTS: In northwestern China, T. absoluta populations established in Xinjiang exhibited a medium PCC value (~0.03). In southwestern China, populations in Yunnan and its five neighboring provinces exhibited high (~0.50 in Yunnan and Guizhou), or low (<0.02 in Guangxi, Sichuan, Hunan, and Chongqing) PCC values. In the Chinese mainland, infestations of four crop plant species (tomato, eggplant, potato, and Chinese lantern) and two wild plant species (black nightshade and Dutch eggplant) were identified; tomatoes were infested in every colonized province. Chinese lantern and Dutch eggplant are potentially novel hosts. Yunnan, Guizhou, and Xinjiang experienced the most serious damage (POI). In southwestern China, observed damage significantly decreased with increased distance from the first discovery site of T. absoluta to the farthest county of an infested province increased. CONCLUSION: T. absoluta populations are well-established and could potentially spread to other regions of China. The present study helps to inform the establishment of better pest management guidelines and strategies in China and tomato-producing regions worldwide. © 2021 Society of Chemical Industry.