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1.
Article in English | MEDLINE | ID: mdl-35845577

ABSTRACT

Jian-Gan-Xiao-Zhi decoction (JGXZ) has demonstrated beneficial effects on nonalcoholic fatty liver disease (NAFLD). However, the mechanisms by which JGXZ improve NAFLD are still unclear. Methods. In this study, we first used a high-fat diet (HFD) to establish a NAFLD rat model to clarify the therapeutic effect of JGXZ on NAFLD. Secondly, we used network pharmacology to predict the potential targets of JGXZ on NAFLD, and then the key targets obtained from network pharmacology were verified. Finally, we used untargeted metabolomics to study the metabolic regulatory mechanism of JGXZ. Results. JGXZ treatment could decrease body weight and ameliorate dyslipidemia in NAFLD model rats. H&E and oil red O staining indicated that JGXZ reduced steatosis and infiltration of inflammatory cells in the liver. In addition, network pharmacology research found that the potential targets of JGXZ on NAFLD pathway were mainly associated with improving oxidative stress, apoptosis, inflammation, lipid metabolism disorders, and insulin resistance. Further experimental verification confirmed that JGXZ could inhibit inflammation and improve oxidative stress, insulin resistance, and lipid metabolism disorders. Serum untargeted metabolomics analyses indicated that the JGXZ in the treatment of NAFLD may work through the linoleic acid metabolism, alpha-linolenic acid metabolism, tryptophan metabolism, and glycerophospholipid metabolism pathways. Conclusions. In conclusion, this study found that JGXZ has an ameliorative effect on NAFLD, and JGXZ alleviates the inflammatory response and oxidative stress and lipid metabolism disorders in NAFLD rats. The mechanism of action of JGXZ in the treatment of NAFLD may be related to the regulation of linoleic acid metabolism, tryptophan metabolism, alpha-linolenic acid metabolism, and glycerophospholipid metabolism.

2.
J Agric Food Chem ; 69(50): 15097-15107, 2021 Dec 22.
Article in English | MEDLINE | ID: mdl-34902254

ABSTRACT

In aphids, hormesis and symbiotic bacteria are the drivers for the development of pesticide resistance. However, the related mechanism remains unclear. Here, we evaluated the sublethal and transgenerational effects of the extensively used pyrethroid pesticide deltamethrin (DMT) on the population dynamics in Aphis gossypii and tested its influence on symbiotic bacterial communities. The leaf-dip bioassay revealed that DMT was highly toxic to A. gossypii, and at a low lethal concentration of DMT, the intrinsic (r) and finite rates of increase (λ) of the initially exposed aphids (G0) significantly decreased. Intriguingly, the r, λ, and net reproductive rate (R0) of G1 and G2 significantly increased, but the r and λ decreased in G3. The adult and total preoviposition period increased in G3 but decreased in G4. Additionally, the diversity of the bacterial community decreased, while the abundance values of Buchnera, Pseudomonadaceae, and Burkholderiaceae increased after 24 h of exposure to LC30 DMT in G0 aphids, and the latter two decreased in G1 but increased in G2. In summary, sublethal DMT has intergenerational hormesis effect on cotton aphids in G1-G2 and remarkably altered their symbiotic bacterial community and abundance. These results broaden our understanding of the relationship of hormesis and symbiotic bacteria in aphids under insecticide exposure.


Subject(s)
Aphids , Insecticides , Pyrethrins , Animals , Bacteria/genetics , Insecticides/toxicity , Nitriles , Pyrethrins/toxicity , Reproduction
3.
Pest Manag Sci ; 77(7): 3406-3418, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33786972

ABSTRACT

BACKGROUND: Aphis gossypii, a polyphagous and recurrent pest induced by pesticides, causes tremendous loss crop yields each year. Previous studies on the mechanism of pesticide-induced sublethal effects mainly focus on the gene level. The symbiotic bacteria are also important participants of this mechanism, but their roles in hormesis are still unclear. RESULTS: In this study, life table parameters and 16S rRNA sequencing were applied to evaluate the sublethal and transgenerational effects of sulfoxaflor on adult A. gossypii after 24-h LC20 (6.96 mg L-1 ) concentration exposure. The results indicated that the LC20 of sulfoxaflor significantly reduced the finite rate of increase (λ) and net reproductive rate (R0 ) of parent generation (G0), and significantly increased mean generation time (T) of G1 and G2, but not of G3 and G4. Both reproductive period and fecundity of G1 and G2 were significantly higher than those of the control. Furthermore, our sequencing data revealed that more than 95% bacterial communities were dominated by the phylum Proteobacteria, in which the maximum proportion genus was the primary symbiont Buchnera and the facultative symbiont Arsenophonus. Compared to those of the control, the abundance and composition of symbiotic bacteria of A. gossypii for three successive generations (G0-G2) were changed after G0 A. gossypii was exposed to sulfoxaflor: the diversity of the bacterial community was decreased, but the abundance of Buchnera was increased (G0), while the abundance of Arsenophonus was decreased. Contrary to G0, G1 and G2 cotton aphid exhibited an increased relative abundance of Arsenophonus in the sublethal treatment group. CONCLUSION: Taken together, our results provide an insight into the interactions among pesticide resistance, aphids, and symbionts, which will eventually help to better manage the resurgence of A. gossypii. © 2021 Society of Chemical Industry.


Subject(s)
Aphids , Animals , Aphids/genetics , Humans , Life Tables , Pyridines , RNA, Ribosomal, 16S/genetics , Sulfur Compounds/toxicity
4.
Am J Trop Med Hyg ; 100(3): 532-539, 2019 03.
Article in English | MEDLINE | ID: mdl-30526730

ABSTRACT

Scrub typhus is caused by the intracellular bacterium Orientia tsutsugamushi. The 56-kDa type-specific antigen (TSA) displays a significant antigenic variation across different O. tsutsugamushi strains. To minimize the influence of the antigenic diversity of TSA on assay sensitivity, we developed a mixed-TSA enzyme-linked immunosorbent assay (mixed-TSA ELISA) using a mixture of recombinant TSAs of prototype (Karp, Gilliam, and Kato) and local (TW-1, TW-10, TW-19, and TW-22) O. tsutsugamushi strains as antigens to detect immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies against O. tsutsugamushi. These four local strains covered a major part of the total genetic diversity of TSA gene of O. tsutsugamushi in Taiwan. A total of 109 acute-phase serum samples from O. tsutsugamushi polymerase chain reaction-positive, scrub typhus patients, and 82 negative control serum samples from non-scrub typhus cases were used for evaluation of the recombinant TSA-based ELISA. We compared the performance of the mixed-TSA ELISA with immunofluorescence assay (IFA), which is considered the gold standard method for the serological diagnosis of scrub typhus. The results indicated that the sensitivity of IgM mixed-TSA ELISA (80.7%) was significantly higher than that of IgM IFA (68.8%). We demonstrated that the mixed-TSA ELISA had a high sensitivity and specificity and can be used for screening of scrub typhus patient in the early phase of the disease.


Subject(s)
Antigens, Bacterial/genetics , Enzyme-Linked Immunosorbent Assay/methods , Orientia tsutsugamushi/immunology , Recombinant Proteins , Scrub Typhus/microbiology , Antibodies, Bacterial/blood , Antibodies, Bacterial/immunology , Antigens, Bacterial/immunology , Gene Expression Regulation, Bacterial , Humans , Orientia tsutsugamushi/genetics , Phylogeny , Real-Time Polymerase Chain Reaction
5.
J Insect Physiol ; 111: 25-31, 2018.
Article in English | MEDLINE | ID: mdl-30336148

ABSTRACT

Chrysoperla sinica is an important natural predator of many notorious agricultural pests. Understanding its olfactory mechanism can help enhance the effectiveness of C. sinica in biological control. In the present study, we investigated the tissue expression patterns of 12 odorant-binding protein (OBP) genes from C. sinica (CsinOBPs). The results of quantitative real-time polymerase chain reaction (qPCR) showed that CsinOBP1, CsinOBP2, CsinOBP3, CsinOBP4, CsinOBP6, CsinOBP7, CsinOBP9, CsinOBP10, and CsinOBP12 were predominantly expressed in the antennae of both sexes, indicating their roles in olfaction. Additionally, the qPCR analysis revealed that the 12 CsinOBP genes had distinct expression patterns, while the motif-pattern investigation suggested that the OBPs had different ligands. The ligand-binding assay showed that CsinOBP1 and CsinOBP10 had broader binding spectra than did the other OBPs. Thus, CsinOBP1 was able to bind not only plant volatiles (such as farnesol, cis-3-hexenyl hexanoate, geranylacetone, ß-ionone, 2-tridecanone, and trans-nerolidol) but also the aphid alarm pheromone (E)-ß-farnesene. On the other hand, CsinOBP2 and CsinOBP6 exhibited relatively narrow binding spectra, only binding ethyl benzoate. The study also identified several compounds that can potentially be used to develop slow-release agents attracting C. sinica and to improve search strategies for insect pest control.


Subject(s)
Insect Proteins/genetics , Insecta/genetics , Pheromones/metabolism , Receptors, Odorant/genetics , Volatile Organic Compounds/metabolism , Amino Acid Sequence , Animals , Female , Gene Expression Profiling , Insect Proteins/metabolism , Male , Predatory Behavior , Protein Binding , Receptors, Odorant/metabolism
6.
PLoS One ; 13(9): e0198570, 2018.
Article in English | MEDLINE | ID: mdl-30216338

ABSTRACT

Saline-alkali soil is an arable land resource on which transgenic Bacillus thuringiensis (Bt) cotton has been planted on a large scale in accordance with food security strategies. There are, however, concerns about the insecticidal effects of Bt cotton on target insect pests. In this study, a Bt cotton variety, GK19, and its nontransgenic parent variety, Simian-3, were used as experimental models for investigating the effect of the expression of exogenous insecticidal proteins in Bt cotton under NaCl stress on the feeding behavior and nutritional parameters of Helicoverpa armigera. The results showed that the expression of exogenous insecticidal proteins in GK19 was significantly inhibited under NaCl stress. However, the feeding, crawling, resting and spinning down behavior of the 5th instar H. armigera larvae on GK19 Bt cotton, as well as the amount of food consumed and feces produced by these larvae, did not markedly differ under different NaCl concentrations. In contrast, the mean relative growth rate (MRGR), relative growth rate (RGR), approximate digestibility (AD), efficiency of conversion of ingested food (ECI) and efficiency of conversion of digested food (ECD) of the larvae markedly decreased in response to NaCl stress. Under the same concentration of NaCl, the nutritional parameters of the bollworm larvae on GK19 Bt cotton or Simian-3 nontransgenic cotton were different. However, the interaction between salt stress and cotton variety had no significant effect on the feeding behavior or nutritional parameters of H. armigera larvae. These results may provide a scientific basis for determining the effect of exogenous insecticidal protein expression in Bt cotton under NaCl stress on H. armigera and can therefore be useful for the effective application of Bt cotton in saline-alkali soils to prevent and control H. armigera.


Subject(s)
Bacillus thuringiensis/genetics , Gossypium/genetics , Herbivory , Moths/physiology , Plants, Genetically Modified/genetics , Salt Stress , Animals , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Gossypium/parasitology , Gossypium/physiology , Insecticides/metabolism , Pest Control, Biological , Plants, Genetically Modified/parasitology , Plants, Genetically Modified/physiology , Sodium Chloride/metabolism
7.
PLoS One ; 12(11): e0188477, 2017.
Article in English | MEDLINE | ID: mdl-29190301

ABSTRACT

Reference genes have been utilized in estimating gene expression levels using quantitative reverse transcriptase-quantitative polymerase chain reaction (qRT-PCR) analysis. Aphidius gifuensis Ashmaed is one of the most widely used biological control agents for aphids. The biological properties of this species have been studied in detail, and current investigations are focused on elucidating the regulatory mechanisms in its host However, the appropriate reference genes for target gene expression studies have not been identified. In this study, the expression profiles of 12 candidate reference genes were evaluated under different experimental conditions(development stage, sex, tissue type, diet) by using dedicated algorithms, including geNorm, Normfinder, BestKeeper, and ΔCt. In addition, RefFinder was used to rank the overall stability of the candidate genes. Finally, we recommend three optimal reference genes for the normalization of qRT-PCR data in the presence of specific variables, which include ACTB, RPL13, and PPI for different developmental stages; RPS18, ACTB, and RPL13 for sexes; RPL13, PRII3, and RPS18 in different tissue types; and RPL13, RPL27, and ACTB in diverse diets. The present study has identified optimal reference genes that could be used in estimating the expression levels of specific genes under these conditions following the Minimum Information for publication of Quantitative real-time PCR Experiments (MIQE) guidelines, which would facilitate in advancements in functional genomics research on A. gifuensis.


Subject(s)
Gene Expression Profiling , Hymenoptera/genetics , Animals , Female , Male , Reverse Transcriptase Polymerase Chain Reaction
8.
Gene ; 637: 211-218, 2017 Dec 30.
Article in English | MEDLINE | ID: mdl-28964897

ABSTRACT

Lysiphlebia japonica (Ashmead) is a predominant parasitoid of cotton-melon aphids in the fields of northern China with a proven ability to effectively control cotton aphid populations in early summer. For accurate normalization of gene expression in L. japonica using quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR), reference genes with stable gene expression patterns are essential. However, no appropriate reference genes is L. japonica have been investigated to date. In the present study, 12 selected housekeeping genes from L. japonica were cloned. We evaluated the stability of these genes under various experimental treatments by RT-qPCR using four independent (geNorm, NormFinder, BestKeeper and Delta Ct) and one comparative (RefFinder) algorithm. We identified genes showing the most stable levels of expression: DIMT, 18S rRNA, and RPL13 during different stages; AK, RPL13, and TBP among sexes; EF1A, PPI, and RPL27 in different tissues, and EF1A, RPL13, and PPI in adults fed on different diets. Moreover, the expression profile of a target gene (odorant receptor 1, OR1) studied during the developmental stages confirms the reliability of the chosen selected reference genes. This study provides for the first time a comprehensive list of suitable reference genes for gene expression studies in L. japonica and will benefit subsequent genomics and functional genomics research on this natural enemy.


Subject(s)
Gene Expression Profiling/standards , Hymenoptera/genetics , Insect Proteins/genetics , Real-Time Polymerase Chain Reaction/methods , Algorithms , Animals , Reference Standards
9.
PLoS One ; 12(5): e0177981, 2017.
Article in English | MEDLINE | ID: mdl-28545139

ABSTRACT

The host plant expansion of host-specialized Aphis gossypii (Glover) has been well studied in the laboratory; however, this phenomenon is poorly understood in the field. Here, we provide a series of laboratory and field experiments to assess the role of zucchini in the host plant expansion of cotton-specialized aphids. We observed that cotton-specialized aphids possessed the ability to expand on a new host plant (cucumber), with individuals first recorded on June 12 and consequently increasing exponentially in number in a field cage. A bioassay experiment showed that aphids from both cotton and cucumber preferred their natal host, but clones from zucchini have a stronger preference for cucumber than cotton or zucchini. A total of 1512 individuals were collected from a cotton field (mixed cotton and cucurbit plot), cotton farmland (cotton alone) and a field cage and sequenced to identify their biotypes. The results for apterous individuals from the cotton field showed that more cucurbit-specialized biotypes occurred on cucumber and more cotton-specialized biotypes occurred on cotton and zucchini. A majority (> 97.0%) of aphids from both the field cage and cotton farmland were cotton-specialized individuals. Consequently, eliminating intermediate host plants may be an effective measure to suppress A. gossypii outbreaks, because cotton and cucumber are often grown together in fields and greenhouses.


Subject(s)
Aphids/physiology , Cucumis sativus/parasitology , Cucurbita/parasitology , Gossypium/parasitology , Agriculture/methods , Animals , Host Specificity , Host-Parasite Interactions , Population Dynamics
10.
PLoS One ; 12(4): e0174712, 2017.
Article in English | MEDLINE | ID: mdl-28369108

ABSTRACT

Lygus pratensis (L.) is an important cotton pest in China, especially in the northwest region. Nymphs and adults cause serious quality and yield losses. However, the genetic structure and geographic distribution of L. pratensis is not well known. We analyzed genetic diversity, geographical structure, gene flow, and population dynamics of L. pratensis in northwest China using mitochondrial and nuclear sequence datasets to study phylogeographical patterns and demographic history. L. pratensis (n = 286) were collected at sites across an area spanning 2,180,000 km2, including the Xinjiang and Gansu-Ningxia regions. Populations in the two regions could be distinguished based on mitochondrial criteria but the overall genetic structure was weak. The nuclear dataset revealed a lack of diagnostic genetic structure across sample areas. Phylogenetic analysis indicated a lack of population level monophyly that may have been caused by incomplete lineage sorting. The Mantel test showed a significant correlation between genetic and geographic distances among the populations based on the mtDNA data. However the nuclear dataset did not show significant correlation. A high level of gene flow among populations was indicated by migration analysis; human activities may have also facilitated insect movement. The availability of irrigation water and ample cotton hosts makes the Xinjiang region well suited for L. pratensis reproduction. Bayesian skyline plot analysis, star-shaped network, and neutrality tests all indicated that L. pratensis has experienced recent population expansion. Climatic changes and extensive areas occupied by host plants have led to population expansion of L. pratensis. In conclusion, the present distribution and phylogeographic pattern of L. pratensis was influenced by climate, human activities, and availability of plant hosts.


Subject(s)
DNA, Mitochondrial/genetics , Genetics, Population , Heteroptera/genetics , Mitochondria/genetics , Animals , China , DNA, Intergenic/genetics , DNA, Ribosomal/genetics , Gene Flow , Genetic Variation , Gossypium/parasitology , Phylogeography , Population Dynamics , Sequence Analysis, DNA
11.
PLoS One ; 12(1): e0170379, 2017.
Article in English | MEDLINE | ID: mdl-28099508

ABSTRACT

An increasing area of transgenic Bacillus thuringiensis (Bt) cotton is being planted in saline-alkaline soil in China. The Bt protein level in transgenic cotton plants and its control efficiency can be affected by abiotic stress, including high temperature, water deficiency and other factors. However, how soil salinity affects the expression of Bt protein, thus influencing the control efficiency of Bt cotton against the cotton bollworm (CBW) Helicoverpa armigera (Hübner) in the field, is poorly understood. Our objective in the present study was to investigate the effects of soil salinity on the expression of Bt toxin (Cry1Ac) and the control efficiency of Helicoverpa armigera in field-grown transgenic Bt cotton using three natural saline levels (1.15 dS m-1 [low soil-salinity], 6.00 dS m-1 [medium soil-salinity] and 11.46 dS m-1 [high soil-salinity]). We found that the Bt protein content in the transgenic Bt cotton leaves and the insecticidal activity of Bt cotton against CBW decreased with the increasing soil salinity in laboratory experiments during the growing season. The Bt protein content of Bt cotton leaves in the laboratory were negatively correlated with the salinity level. The CBW populations were highest on the Bt cotton grown in medium-salinity soil instead of the high-salinity soil in field conditions. A possible mechanism may be that the relatively high-salinity soil changed the plant nutritional quality or other plant defensive traits. The results from this study may help to identify more appropriate practices to control CBW in Bt cotton fields with different soil salinity levels.


Subject(s)
Bacterial Proteins/biosynthesis , Endotoxins/biosynthesis , Gossypium/genetics , Gossypium/metabolism , Hemolysin Proteins/biosynthesis , Moths/drug effects , Plants, Genetically Modified/genetics , Salinity , Soil/chemistry , Animals , Bacillus thuringiensis/genetics , Bacillus thuringiensis Toxins , Insecticide Resistance/physiology , Insecticides/metabolism , Larva/drug effects , Seasons
12.
Sci Rep ; 6: 22958, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-27079679

ABSTRACT

Aphids are infected with a wide variety of endosymbionts that can confer ecologically relevant traits. However, the bacterial communities of most aphid species are still poorly characterized. This study investigated the bacterial diversity of the cotton aphid Aphis gossypii associated with Bt cotton in northern China by targeting the V4 region of the 16S rDNA using the Illumina MiSeq platform. Our sequencing data revealed that bacterial communities of A. gossypii were generally dominated by the primary symbiont Buchnera, together with the facultative symbionts Arsenophonus and Hamiltonella. To our knowledge, this is the first report documenting the facultative symbiont Hamiltonella in A. gossypii. Moreover, the bacterial community structure was similar within aphids from the same province, but distinct among those from different provinces. The taxonomic diversity of the bacterial community is greater in Hebei Province compared with in samples from Henan and Shandong Provinces. The selection pressure exerted by the different geographical locations could explain the differences found among the various provinces. These findings broaden our understanding of the interactions among aphids, endosymbionts and their environments, and provide clues to develop potential biocontrol techniques against this cotton aphid.


Subject(s)
Aphids/microbiology , Bacteria/classification , Microbiota , Animals , Bacteria/genetics , Biodiversity , China , Cluster Analysis , Gossypium/parasitology , RNA, Ribosomal, 16S/genetics
13.
PLoS One ; 11(3): e0152103, 2016.
Article in English | MEDLINE | ID: mdl-27002824

ABSTRACT

Aphis gossypii Glover (Hemiptera: Aphididae) is a serious pest of cotton in northern China. A microsatellite analysis was used to characterize the genetic structure of A. gossypii populations from different geographic, host plant, and seasonal populations in 2014. Among 906 individuals, 507 multilocus genotypes were identified, with genotypic richness values of 0.07-1.00 for the populations. We observed moderate levels of genetic differentiation among geographic populations (FST = 0.103; 95% confidence interval: 0.065-0.145) and host plant populations (FST = 0.237; 95% confidence interval: 0.187-0.296). A Mantel test of isolation by distance revealed no significant correlations between Slatkin's linearized FST and the natural logarithm of geographic distance. A Bayesian analysis of population genetic structures identified three clusters. An analysis of molecular variance revealed significant differences among the three clusters (F = 0.26596, P < 0.0001), among seasons (F = 0.04244, P = 0.00381), and among host populations (F = 0.12975, P = 0.0029). Thus, the A. gossypii populations in northern China exhibit considerable genotypic diversity. Additionally, our findings indicated that the 31 analyzed populations could be classified as one of three host biotypes (i.e., cotton, cucumber, and pomegranate biotypes). There were also clear seasonal effects on population genetic structure diversity among aphids collected from Anyang.


Subject(s)
Aphids/genetics , Genetic Variation/genetics , Animals , Bayes Theorem , China , Genetics, Population/methods , Gossypium/genetics , Microsatellite Repeats/genetics , Plants , Seasons
14.
Sci Rep ; 6: 20368, 2016 Feb 01.
Article in English | MEDLINE | ID: mdl-26829252

ABSTRACT

Plant varieties expressing the Bt (Bacillus thuringiensis) insecticidal proteins Cry1Ah and Cry2Ab have potential commercialization prospects in China. However, their potential effects on non-target arthropods (NTAs) remain uncharacterized. The cotton aphid Aphis gossypii is a worldwide pest that damages various important crops. The ladybeetle Propylea japonica is a common and abundant natural enemy in many cropping systems in East Asia. In the present study, the effects of Cry1Ah and Cry2Ab proteins on A. gossypii and P. japonica were assessed from three aspects. First, neither of the Cry proteins affected the growth or developmental characteristics of the two test insects. Second, the expression levels of the detoxification-related genes of the two test insects did not change significantly in either Cry protein treatment. Third, neither of the Cry proteins had a favourable effect on the expression of genes associated with the amino acid metabolism of A. gossypii and the nutrition utilization of P. japonica. In conclusion, the Cry1Ah and Cry2Ab proteins do not appear to affect the cotton aphid A. gossypii or the ladybeetle P. japonica.


Subject(s)
Aphids/drug effects , Aphids/physiology , Bacillus thuringiensis/metabolism , Bacterial Proteins/pharmacology , Coleoptera/drug effects , Coleoptera/physiology , Endotoxins/pharmacology , Hemolysin Proteins/pharmacology , Insect Control , Amino Acids/metabolism , Animals , Bacillus thuringiensis Toxins , Bacterial Proteins/administration & dosage , Endotoxins/administration & dosage , Gene Expression Regulation/drug effects , Genes, Insect , Gossypium/genetics , Gossypium/parasitology , Hemolysin Proteins/administration & dosage , Inactivation, Metabolic/genetics , Plants, Genetically Modified
15.
PLoS One ; 11(1): e0146345, 2016.
Article in English | MEDLINE | ID: mdl-26735973

ABSTRACT

BACKGROUND: The cotton-melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is a polyphagous species with a worldwide distribution and a variety of biotypes. North China is a traditional agricultural area with abundant winter and summer hosts of A. gossypii. While the life cycles of A. gossypii on different plants have been well studied, those of the biotypes of North China are still unclear. RESULTS: Host transfer experiments showed that A. gossypii from North China has two host-specialized biotypes: cotton and cucumber. Based on complete mitochondrial sequences, we identified a molecular marker with five single-nucleotide polymorphisms to distinguish the biotypes. Using this marker, a large-scale study of biotypes on primary winter and summer hosts was conducted. All A. gossypii collected from three primary hosts-hibiscus, pomegranate, and Chinese prickly ash-were cotton biotypes, with more cotton-melon aphids found on hibiscus than the other two species. In May, alate cotton and cucumber biotypes coexisted on cotton and cucumber seedlings, but each preferred its natal host. Both biotypes existed on zucchini, although the cucumber biotype was more numerous. Aphids on muskmelon were all cucumber biotypes, whereas most aphids on kidney bean were cotton biotypes. Aphids on seedlings of potato and cowpea belong to other species. In August, aphids on cotton and cucumber were the respective biotypes, with zucchini still hosting both biotypes as before. Thus, the biotypes had different fitnesses on different host plants. CONCLUSIONS: Two host-specialized biotypes (cotton and cucumber) are present in North China. Hibiscus, pomegranate, and Chinese prickly ash can serve as winter hosts for the cotton biotype but not the cucumber biotype in North China. The fitnesses of the two host-specialized biotypes differ on various summer hosts. When alate aphids migrate to summer hosts, they cannot accurately land on the corresponding plant.


Subject(s)
Aphids/genetics , Plant Diseases/parasitology , Animals , Base Sequence , China , Cucumis sativus/parasitology , DNA, Mitochondrial/genetics , Genes, Insect , Gossypium/parasitology , Host Specificity , Host-Parasite Interactions , Molecular Sequence Data , Molecular Typing , Plant Leaves/parasitology , Seasons , Sequence Analysis, DNA
16.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4059-4060, 2016 11.
Article in English | MEDLINE | ID: mdl-25600739

ABSTRACT

The complete mitochondrial genome of the Chrysoperla sinica was sequenced in this study. It is 16,057 bp in length, and contains 22 transfer RNA genes, 13 protein-coding genes (PCGs), 2 rRNA genes and 1 non-coding AT-rich region. But, C. sinica lack long tandem repeats. The Chrysoperla sinica mitogenome displays a very high level of similarity (99.27%) with Chrysoperla nipponensis. The genome base composition is 39.24% A, 39.70% T, 11.98% C, and 9.08% G. Similar to other insects, all PCGs are initiated by a typical ATN codon, except COX1, which starts with TCG. Nine PCGs have the standard, complete stop codon (TAA or TAG), and the other four PCGs end with the incomplete stop codon (TA or T).


Subject(s)
Genome, Insect/genetics , Genome, Mitochondrial/genetics , Insecta/genetics , Animals , Base Composition/genetics , Codon, Initiator/genetics , Codon, Terminator/genetics , DNA, Mitochondrial/genetics , RNA, Ribosomal/genetics , RNA, Transfer/genetics , Sequence Analysis, DNA/methods
17.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 3882-3883, 2016 11.
Article in English | MEDLINE | ID: mdl-25541303

ABSTRACT

The complete mitochondrial genome of the tobacco budworm Helicoverpa assulta was sequenced. It is 15,351 bp in length, and contains 22 transfer RNA genes, 13 protein-coding genes (PCGs), 2 rRNA genes and a non-coding AT-rich region. The H. assulta mitogenome displays a very high level of identity (99.76%) with Helicoverpa armigera. The genome base composition is 40.50% A, 40.40% T, 11.32% C and 7.70% G. Similar to other Lepidoptera insects, all PCGs are initiated by a typical ATN codon, except CO1, which starts with CGA. Nine PCGs have the standard, complete stop codon (TAA), and the other four PCGs end with the incomplete stop codon TA-.

18.
Ying Yong Sheng Tai Xue Bao ; 27(11): 3675-3681, 2016 Nov 18.
Article in Chinese | MEDLINE | ID: mdl-29696867

ABSTRACT

The ecological fitness of transgenic cotton and its effects on the insect communities in cotton fields is one of the key aspects of the evaluation of the environmental safety of transgenic cotton. New transgenic GAFP (Gastrodia anti-fungal protein) cotton and its parental varieties were used in this study to explore their ecological fitness and their effects on insect community infield in Anyang, Henan Province in 2013 and 2014. The results showed that there was no significant difference in dry mass for transgenic cotton leaves compared to that of parental cotton. Specific leaf areas of transgenic cotton were lowered obviously at seedling stage, while enhanced significantly at budding, flowering and bolling stages relative to parental cotton. The plant height of transgenic cotton was lowered only at seedling stage, and no significant difference was showed between the two cultivars at budding, flowering and bolling stages. No significant differences were discovered on plant branch numbers, bud numbers and falling numbers between the transgenic cotton and control material in any of the four key stages during the cotton growth. However, the number of bolls per plant for transgenic cotton was lower than that of the control cotton at the bolling stage. In the 2nd, 3rd, and 4th generation of cotton bollworm (Helicoverpa armigera), the mortality rate of cotton bollworm and beet armyworm (Spodoptera exigua) of transgenic cotton had no significant difference with parental cotton. Compared to parental cotton, total individuals of insect community, pest sub-communities and enemy sub-communities in transgenic cotton field didn't show any significant difference. The above results showed that after the GAFP gene was imported into cotton, the cotton growth was enhanced significantly, while the whole yield component traits and the insect community in the field were not significantly changed. Our study on the competition of new transgenic cotton and survival of transgenic cotton insect communities in cotton field would provide the theoretical basis for the evaluation of new transgenic cotton and environmental safety, and accumulate scientific data for environmental safety evaluation of the transgenic cotton.


Subject(s)
Gossypium/growth & development , Insecta , Spodoptera , Animals , Ecology , Ecosystem , Gossypium/genetics , Plant Leaves , Plants, Genetically Modified/growth & development
19.
Yi Chuan ; 37(6): 575-81, 2015 06.
Article in Chinese | MEDLINE | ID: mdl-26351054

ABSTRACT

In this study, we detected and clarified the roles of transgenic Cry1Ac+Cry2Ab cotton "639020" in controlling cotton bollworm (Helicoverpa armigera) during critical periods of bud stage (second generation of bollworm), flowering stage (third generation of bollworm) and bolling stage (fourth generation of bollworm) as well as the influences of 639020 cotton on functional response of the main predators (Chrysopa sinica larvae, Propylaea japonica, Orius and Erigonidium graminicola ) on whitefly using transgenic Cry1Ac cotton "CCRI41" and conventional cotton "CCRI49" as the control. Our results showed that the 639020 cotton well controlled the second and third generation of bollworm, and the level of insect resistance increased by 52.85% and 16.22% separately compared with that of CCRI41, with a significant effect on the second generation of bollworm. Moreover, the number of bollworm eggs in 639020 cotton field was lower than that in CCRI41 and CCRI49 cotton fields (except the second generation of bollworm) during the cotton bud, flowering and bolling stages. Although the number of bollworm larvae in 639020 cotton field was significantly lower than that in CCRI49 field, and both under the controlling index, it has no significant difference compared with that in CCRI41 cotton field. There were also no obvious changes in predator functions of Chrysopa sinica, Propylaea japonica, Orius and Erigonidium graminicola on bemisia tabaci between 639020, CCRI41 and CCRI49 cotton filed. This study evaluated the safety of new transgenic cotton on environment, anti-insect activity of exogenous gene and the safety of production and application prospect.


Subject(s)
Bacterial Proteins/genetics , Endotoxins/genetics , Gossypium/genetics , Hemiptera , Hemolysin Proteins/genetics , Insect Control , Lepidoptera , Plants, Genetically Modified , Animals , Bacillus thuringiensis Toxins , Predatory Behavior
20.
Article in English | MEDLINE | ID: mdl-26072463

ABSTRACT

Chrysoperla sinica is one of the most prominent natural enemies of many agricultural pests. Host seeking in insects is strongly mediated by olfaction. Understanding the sophisticated olfactory system of insect antennae is crucial for studying the physiological bases of olfaction and could also help enhance the effectiveness of C. sinica in biological control. Obtaining olfactory genes is a research priority for investigating the olfactory system in this species. However, no olfaction sequence information is available for C. sinica. Consequently, we sequenced female- and male-antennae transcriptome of C. sinica. Many candidate chemosensory genes were identified, including 12 odorant-binding proteins (OBPs), 19 chemosensory proteins (CSPs), 37 odorant receptors (ORs), and 64 ionotropic receptors from C. sinica. The expression patterns of 12 OBPs, 19 CSPs and 37 ORs were determined by RT-PCR, and demonstrated antennae-dominantly expression of most OBP and OR genes. Our finding provided large scale genes for further investigation on the olfactory system of C. sinica at the molecular level.


Subject(s)
Gene Expression Profiling/methods , Insecta/genetics , Animals , Arthropod Antennae/metabolism , Female , Insect Proteins/genetics , Male
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