[Bacterial community diversity in human Demodex mites]

OBJECTIVE

To investigate the bacterial community diversity in human Demodex mites, so as to provide insights into unraveling the role of human Demodex mites in them caused infectious diseases.

METHODS

From June to July 2023, Demodex mites were collected from the faces of college students in a university in Wuhu City using the adhesive tape method, and the V4 region of 16S ribosomal RNA (16S rRNA) gene and the internal transcribed spacer (ITS) gene of nuclear ribosomal DNA were amplified on an Illumina PE250 high-throughput sequencing platform. Sequencing data were spliced according to the overlapping relations and filtered to yield effective sequences, and operational taxonomic units (OTUs) was clustered. The diversity index of obtained OUTs was analyzed, and the structure of the bacterial community was analyzed at various taxonomic levels.

RESULTS

A total of 57 483 valid sequences were obtained using 16S rRNA gene sequencing, and 159 OUTs were classified according to similarity. Then, OUTs at a 97% similarity were included for taxonomic analyses, and the bacteria in Demodex mites belonged to 14 phyla, 20 classes, 51 orders, 72 families, and 94 genera. Proteobacteria was the dominant phylum, and Vibrio, Bradyrhizobium and Variovorax were dominant genera. A total of 56 362 valid sequences were obtained using ITS gene sequencing, and 147 OTUs were obtained, which belonged to 5 phyla, 17 classes, 34 orders, 68 families, and 93 genera and were annotated to Ascomycota, Basidiomycota and Chytridiomycota, with Ascomycota as the dominant phylum, and Alternaria alternata, Epicoccum, Penicillium, and Sarocladium as dominant genera.

CONCLUSIONS

There is a high diversity in the composition of bacterial communities in human Demodex mites, with multiple types of microorganisms and high species abundance.

Effects of propofol intravenous general anesthesia and inhalational anesthesia on T-lymphocyte activity after breast cancer surgery: A meta-analysis

Background

Breast cancer is one of the most common cancers in women. General anesthesia is a commonly used anesthesia method for breast cancer surgery, and studies have confirmed that general anesthesia can induce immunosuppression in breast cancer patients and increase the metastasis rate of tumors. However, the difference between the effects of intravenous general anesthesia and inhalation anesthesia on the function of T-lymphocytes is still controversial, and it is necessary to explore reasonable anesthesia methods to reduce immunosuppression caused by surgery and anesthesia.

Materials and Methods

Databases (Embase, PubMed, Cochrane Library, CBM, CNKI, and Wanfang) were searched (up to October 2022) for randomized controlled trials (RCTs) comparing intraoperative inhalation anesthesia and propofol intravenous anesthesia in breast cancer patients, with the outcome of T-lymphocyte subsets. The meta-analysis was performed by STATA 14.0.

Results

Six RCTs with 352 patients were included in the study. Compared with inhalation anesthesia, there was no difference in T-lymphocyte subsets between the two groups immediately after surgery, but the activities of CD4+ T cells in patients with propofol anesthesia were higher (standard mean difference [SMD] = 0.234, 95% confidence interval [CI]: 0.003-0.466, P = 0.047, I2 = 44.1%) than those under inhalation anesthesia 1 day after surgery, and CD4+/CD8+ activities in patients with propofol anesthesia were higher (SMD = 304, 95% CI: 0.072-0.537, P = 0.010, I2 = 48.0%) than those under inhalation anesthesia 1 day after surgery.

Conclusion

There were no differences in the effects of propofol and inhalation anesthetics on T-lymphocytes immediately after surgery, but the inhibitory effects of inhalation anesthetics on CD4+ and CD4+/CD8+ cells were stronger 1 day after surgery.

Social media unveils the hidden but high magnitude of human-mediated biological invasions in China

Humans are responsible for the release of many non-native animals into the wild. However, these releases occur randomly and are difficult to monitor. Here, using two of the worst invasive herpetofauna as model taxa, we applied an iEcology approach and found a high magnitude of human-mediated releases in China, suggesting this approach can be used to monitor introductions and advise management bodies in a timely manner.

Climate match is key to predict range expansion of the world's worst invasive terrestrial vertebrates

Understanding the determinants of the range expansion of invasive alien species is crucial for developing effective prevention and control strategies. Nevertheless, we still lack a global picture of the potential factors influencing the invaded range expansion across taxonomic groups, especially for the world's worst invaders with high ecological and economic impacts. Here, by extensively collecting data on 363 distributional ranges of 19 of world's worst invasive terrestrial vertebrates across 135 invaded administrative jurisdictions, we observed remarkable variations in the range expansion across species and taxonomic groups. After controlling for taxonomic and geographic pseudoreplicates, model averaging analyses based on generalized additive mixed-effect models showed that species in invaded regions having climates more similar to those of their native ranges tended to undergo a larger range expansion. In addition, as proxies of propagule pressure and human-assisted transportation, the number of introduction events and the road network density were also important predictors facilitating the range expansion. Further variance partitioning analyses validated the predominant role of climate match in explaining the range expansion. Our study demonstrated that regions with similar climates to their native ranges could still be prioritized to prevent the spread of invasive species under the sustained global change.

Meta-analysis reveals less sensitivity of non-native animals than natives to extreme weather worldwide

Extreme weather events (EWEs; for example, heatwaves, cold spells, storms, floods and droughts) and non-native species invasions are two major threats to global biodiversity and are increasing in both frequency and consequences. Here we synthesize 443 studies and apply multilevel mixed-effects metaregression analyses to compare the responses of 187 non-native and 1,852 native animal species across terrestrial, freshwater and marine ecosystems to different types of EWE. Our results show that marine animals, regardless of whether they are non-native or native, are overall insensitive to EWEs, except for negative effects of heatwaves on native mollusks, corals and anemone. By contrast, terrestrial and freshwater non-native animals are only adversely affected by heatwaves and storms, respectively, whereas native animals negatively respond to heatwaves, cold spells and droughts in terrestrial ecosystems and are vulnerable to most EWEs except cold spells in freshwater ecosystems. On average, non-native animals displayed low abundance in terrestrial ecosystems, and decreased body condition and life history traits in freshwater ecosystems, whereas native animals displayed declines in body condition, life history traits, abundance, distribution and recovery in terrestrial ecosystems, and community structure in freshwater ecosystems. By identifying areas with high overlap between EWEs and EWE-tolerant non-native species, we also provide locations where native biodiversity might be adversely affected by their joint effects and where EWEs might facilitate the establishment and/or spread of non-native species under continuing global change.

Search for Λ[over ¯]-Λ Baryon-Number-Violating Oscillations in the Decay J/ψ→pK^{-}Λ[over ¯]+c.c

We report on the first search for Λ[over ¯]-Λ oscillations in the decay J/ψ→pK^{-}Λ[over ¯]+c.c. by analyzing 1.31×10^{9}  J/ψ events accumulated with the BESIII detector at the BEPCII collider. The J/ψ events are produced using e^{+}e^{-} collisions at a center of mass energy sqrt[s]=3.097  GeV. No evidence for hyperon oscillations is observed. The upper limit for the oscillation rate of Λ[over ¯] to Λ hyperons is determined to be P(Λ)=[B(J/ψ→pK^{-}Λ+c.c.)/B(J/ψ→pK^{-}Λ[over ¯]+c.c.)]<4.4×10^{-6} corresponding to an oscillation parameter δm_{ΛΛ[over ¯]} of less than 3.8×10^{-18}  GeV at the 90% confidence level.

Intestinal microenvironment-mediated allergic dynamic phenotypes and endotypes in the development of gluten allergy

This study aimed to investigate the dynamic changes in intestinal microenvironment factors in the development of gluten-induced allergy (GA). Our results showed that GA provoked increasingly severe allergic phenotypes such as allergic and diarrheal symptoms with the gluten sensitization frequency, which was accompanied by dynamically rising levels of gluten-specific immunoglobulin (Ig) E, IgG2a and IgA, serum histamine, T cell-related inflammatory cytokines, and intestinal indexes. An increase in luminal pH was more significant in the large intestine versus the small intestine, which was due to a dynamic decline in colonic short-chain fatty acid levels. Both antioxidant capacity and intestinal permeability in the large intestine varied with the GA severity, as evidenced by a dynamic increase in the malondialdehyde content and a decrease in the superoxide dismutase activity and total antioxidant capacity. Moreover, we demonstrated that intestinal microenvironment dysbiosis occurred before a true allergy reaction began. Spearman correlation analysis suggested that the characteristic bacterial cluster, namely Alistipes, Desulfovibrio, Ileibacterium, Parabacteroides, and Ruminococcus torques group, are essential in the association between GA and intestinal microenvironment homeostasis.

Increasing the pressure during high pressure homogenization regulates the starch digestion of the resulting pea starch-gallic acid complexes

The pea starch-gallic acid (PS-GA) complexes were prepared using high pressure homogenization (HPH), then the effect and underlying mechanism of pressure on multi-scale structure and digestibility of complexes were investigated. Results showed that HPH promoted the formation of PS-GA complexes, reaching the maximum complex index of 7.74 % at the pressure of 90 MPa, and the main driving force were hydrophobic interactions and hydrogen bonding. The interaction between PS and GA facilitated the formation of surface reticular structures to encapsulate gallic acid molecules, further entangled into bigger size aggregates. The enhancement of rearrangement and aggregation of starch chains during HPH developed a dense hierarchical structure of PS-GA complexes, including short-range ordered structure, V-type crystal structure, lamellar and fractal structure, thus increasing gelatinization temperature. The digestibility of PS-GA complexes substantially changed in reducing rapidly digestible starch content from 29.67 % to 17.07 %, increasing slowly digestible starch from 53.69 % to 56.25 % and resistant starch from 16.63 % to 26.67 %, respectively. Moreover, the resulting complexes exhibited slower digestion rates compared with native PS. Furthermore, the regulating mechanism of pressure during HPH on starch digestibility was the formation of ordered multi-scale structure and inhibition of GA on digestive enzymes.

The high dose of inulin exacerbated food allergy through the excess accumulation of short-chain fatty acids in a BABL/c mouse model

Inulin dietary supplement is conventionally beneficial to gut health and can potentially prevent food allergy (FA). This study aimed to determine how dietary inulin interventions at different doses affect the OVA-induced FA in a BALB/c mouse model. Although the middle dose of inulin (50 mg per mouse) showed the best therapeutic effect on FA, high-inulin supplementation (80 mg per mouse) provoked severe allergic and intestinal inflammatory responses, which were characterized by elevated serum allergic inflammation-related factor levels, dysfunctional gut barrier, unbalanced luminal pH value, decrease in intestinal antioxidant capacity, and disordered gut microecology. Moreover, profiling of SCFAs indicated that the high-inulin-induced excess accumulation of SCFAs in the colon was responsible for the gut immune disorders. Spearman correlation analysis unraveled that the featured bacterial taxa in the high-inulin-treated mice were Ruminococcaceae and Bifidobacterium, of which the relative abundance was negatively correlated with expression of tight junction proteins and improvement of T cell homeostasis, and positively correlated with levels of allergic inflammation-related indexes. Our work suggested that high-inulin dietary supplementation can be detrimental to allergic individuals and highlighted the importance for personalized use of inulin-type dietary supplements to safely improve human health.

Preferred prey reduce species realized niche shift and improve range expansion prediction

Many studies have detected realized climatic niche shifts during range changes; this is challenging the fundamental theory of the niche conservatism hypothesis (NCH) and the usefulness of the ecological niche model (ENM) for predicting the distributions of species in space and time by tracking environmental change. Biotic factors such as predatory interactions are important components of species realized niches but are generally difficult to quantify during NCH testing and ENM building. Identifying species' preferred prey may provide a unique opportunity to include trophic interactions in assessing the NCH and determine whether more precise ENM predictions are generated. In this study, we focused on a range-expanding predatory bird, the Asian openbill (Anastomus oscitans). The main prey of the Asian openbill include 136 snail species. We observed a realized climatic niche shift during the northward expansion of the Asian openbill by considering only climates; however, niche conservatism was detected after incorporating their preferred prey. ENMs including preferred snails also predicted the distributions of the Asian openbill better than climate-only models and models including nonpreferred snails or only habitat variables. The results of our study suggested the importance of incorporating preferred prey in evaluating the NCH and developing a framework for predicting the range shifts of both native and alien species in response to global climate change.

Complex origins indicate a potential bridgehead introduction of an emerging amphibian invader (Eleutherodactylus planirostris) in China

Identifying the origins of established alien species is important to prevent new introductions in the future. The greenhouse frog (Eleutherodactylus planirostris), native to Cuba, the Bahamas, and the Cayman Islands, has been widely introduced to the Caribbean, North and Central America, Oceania and Asia. This invasive alien amphibian was recently reported in Shenzhen, China, but the potential introduction sources remain poorly understood. Based on phylogenetic analysis using mitochondrial 16S, COI and CYTB sequences, we detected a complex introduction origin of this species, which may be from Hong Kong, China, the Philippines, Panama and Florida, USA, all pointing to a bridgehead introduction. In addition, the nursery trade between the four countries or regions and mainland China from 2011 to 2020 was also significantly higher than other areas with less likelihood of introductions, which supported the molecular results. Our study provides the first genetic evidence of the potential sources of this emerging amphibian invader in mainland China, which may help develop alien species control strategies in the face of growing trade through globalization.

[Analysis of 42 cases of childhood superior vena cava syndrome associated with mediastinal malignancy]

Objective: To summarize the clinical features, management and outcome of superior vena cava syndrome (SVCS) associated with mediastinal malignancy in children. Methods: Clinical data of 42 children of SVSC associated with mediastinal malignancy in Shanghai Children's Medical Center from January 2015 to December 2021 were collected and analyzed retrospectively. The clinical manifestations, pathological diagnosis, disease diagnosis process, and prognosis were summarized. Results: Among 42 children of SVCS associated with mediastinal malignancy, there were 31 males and 11 females. The age at diagnosis was 8.5 (1.9, 14.9) years. Cough and wheezing (33 cases, 79%), orthopnea (19 cases, 45%) and facial edema (18 cases, 43%) occurred most commonly. T-cell lymphoblastic lymphoma (T-LBL) was the most frequent pathological diagnosis (25 cases, 60%), followed by T-cell acute lymphoblastic leukemia (T-ALL) (7 cases, 17%), anaplastic large cell lymphoma (4 cases, 10%) and diffuse large B-cell lymphoma (2 cases, 5%), peripheral T-lymphoma, Hodgkin lymphoma, Ewing's sarcoma and germ cell tumor (1 case each). Pathological diagnosis was confirmed by bone marrow aspiration or thoracentesis in 14 cases, peripheral lymph node biopsy in 6 cases, and mediastinal biopsy in 22 cases. Twenty-seven cases (64%) had local anesthesia. Respiratory complications due to mediastinal mass developed in 3 of 15 cases who received general anesthesia. Of the 42 cases, 27 cases had sustained remission, 1 case survived with second-line therapy after recurrence, and 14 cases died (2 cases died of perioperative complications and 12 cases died of recurrence or progression of primary disease). The follow-up time was 36.7 (1.2, 76.1) months for 27 cases in continuous complete remission. The 3-year overall survival (OS) and events free survival (EFS) rates of 42 children were 59% (95%CI 44%-79%) and 58% (95%CI 44%-77%) respectively. Conclusions: SVCS associated with mediastinal malignancy in children is a life-threatening tumor emergency with high mortality. The most common primary disease is T-LBL. The most common clinical symptoms and signs are cough, wheezing, orthopnea and facial edema. Clinical management should be based on the premise of stable critical condition and confirm the pathological diagnosis through minimal invasive operation.

Potato starch films by incorporating tea polyphenol and MgO nanoparticles with enhanced physical, functional and preserved properties

Due to the massive environmental pollution caused by synthetic plastic packaging accumulation and contemporary necessities of food packaging materials, the biodegradable and multifunctional bionanocomposite films based on potato starch (PS) incorporating tea polyphenol (TP) and MgO nanoparticles (MgO-NPs) were successfully fabricated by the solution casting method, and their physical and functional properties and application in fruits preservation were systematically investigated. Incorporation of TP and MgO-NPs improved the films' tensile strength, UV light-blocking, hydrophobicity and thermal stability, and decreased their moisture content (from 14.02 % to 11.21 %), water solubility (from 19.57 % to 16.56 %), and water vapor permeability (from 17.32 to 9.07 × 10^-11 g∙m^-1∙s^-1∙Pa^-1). Moreover, the PS/TP/MgO-NPs films exhibited strong antioxidant activity, and remarkable antibacterial activity against Escherichia coli and Staphylococcus aureus with the diameter of inhibition zone of 25.60 mm and 27.50 mm, respectively. SEM, ATR-FTIR and XRD analyses indicated the TP and MgO-NPs were dispersed homogeneously in the PS matrix, and identified the molecular interactions of hydrogen bond, hydrophobic interaction and electrostatic attraction. Biodegradability assessment showed that all the films were rapidly decomposed within ~20 days under simulated environmental conditions. Compared to control, the PS/TP/MgO-NPs film-forming solution coatings were capable of maintaining fruit quality by reducing the change in weight loss, firmness and total soluble solids. Overall, these results suggested that the multifunctional bionanocomposite films could be a potential approach for developing sustainable active food packaging.

Observation of J/ψ Electromagnetic Dalitz Decays to X(1835), X(2120), and X(2370)

Using a sample of about 10^{10}  J/ψ events collected at a center-of-mass energy sqrt[s]=3.097  GeV with the BESIII detector, the electromagnetic Dalitz decays J/ψ→e^{+}e^{-}π^{+}π^{-}η^{'}, with η^{'}→γπ^{+}π^{-} and η^{'}→π^{+}π^{-}η, have been studied. The decay J/ψ→e^{+}e^{-}X(1835) is observed with a significance of 15σ, and also an e^{+}e^{-} invariant-mass dependent transition form factor of J/ψ→e^{+}e^{-}X(1835) is presented for the first time. The intermediate states X(2120) and X(2370) are also observed in the π^{+}π^{-}η^{'} invariant-mass spectrum with significances of 5.3σ and 7.3σ. The corresponding product branching fractions for J/ψ→e^{+}e^{-}X, X→π^{+}π^{-}η^{'} [X=X(1835), X(2120), and X(2370)] are reported.

Probing CP symmetry and weak phases with entangled double-strange baryons

Though immensely successful, the standard model of particle physics does not offer any explanation as to why our Universe contains so much more matter than antimatter. A key to a dynamically generated matter-antimatter asymmetry is the existence of processes that violate the combined charge conjugation and parity (CP) symmetry1. As such, precision tests of CP symmetry may be used to search for physics beyond the standard model. However, hadrons decay through an interplay of strong and weak processes, quantified in terms of relative phases between the amplitudes. Although previous experiments constructed CP observables that depend on both strong and weak phases, we present an approach where sequential two-body decays of entangled multi-strange baryon-antibaryon pairs provide a separation between these phases. Our method, exploiting spin entanglement between the double-strange Ξ- baryon and its antiparticle2 [Formula: see text], has enabled a direct determination of the weak-phase difference, (ξP - ξS) = (1.2 ± 3.4 ± 0.8) × 10-2 rad. Furthermore, three independent CP observables can be constructed from our measured parameters. The precision in the estimated parameters for a given data sample size is several orders of magnitude greater than achieved with previous methods3. Finally, we provide an independent measurement of the recently debated Λ decay parameter αΛ (refs. 4,5). The [Formula: see text] asymmetry is in agreement with and compatible in precision to the most precise previous measurement4.

Pediococcus acidilactici Strain Alleviates Gluten-Induced Food Allergy and Regulates Gut Microbiota in Mice

Wheat flour, the most important source of food globally, is also one of the most common causative agents of food allergy. Wheat gluten protein, which accounts for 80% of the total wheat protein, is a major determinant of important wheat-related disorders. In this study, the effects of Pediococcus acidilactici XZ31 against gluten-induced allergy were investigated in a mouse model. The oral administration of P. acidilactici XZ31 attenuated clinical and intestinal allergic responses in allergic mice. Further results showed that P. acidilactici XZ31 regulated Th1/Th2 immune balance toward Th1 polarization, which subsequently induced a reduction in gluten-specific IgE production. We also found that P. acidilactici XZ31 modulated gut microbiota homeostasis by balancing the Firmicutes/Bacteroidetes ratio and increasing bacterial diversity and the abundance of butyrate-producing bacteria. Specifically, the abundance of Firmicutes and Erysipelotrichaceae is positively correlated with concentrations of gluten-specific IgE and may act as a fecal biomarker for diagnosis. The evidence for the role of P. acidilactici XZ31 in alleviating gluten-induced allergic responses sheds light on the application of P. acidilactici XZ31 in treating wheat allergy.

First Measurement of Polarizations in the Decay D^{0}→ωφ

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy sqrt[s]=3.773  GeV by the BESIII detector, the decay D^{0}→ωϕ is observed for the first time. The branching fraction is measured to be (6.48±0.96±0.40)×10^{-4} with a significance of 6.3σ, where the first and second uncertainties are statistical and systematic, respectively. An angular analysis reveals that the ϕ and ω mesons from the D^{0}→ωϕ decay are transversely polarized. The 95% confidence level upper limit on longitudinal polarization fraction is set to be less than 0.24, which is inconsistent with current theoretical expectations and challenges our understanding of the underlying dynamics in charm meson decays.

Measurement of the Absolute Branching Fraction of D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}

Using a dataset of 6.32  fb^{-1} of e^{+}e^{-} annihilation data collected with the BESIII detector at center-of-mass energies between 4178 and 4226 MeV, we have measured the absolute branching fraction of the leptonic decay D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}, and find B_{D_{s}^{+}→τ^{+}ν_{τ}}=(5.27±0.10±0.12)×10^{-2}, where the first uncertainty is statistical and the second is systematic. The precision is improved by a factor of 2 compared to the previous best measurement. Combining with f_{D_{s}^{+}} from lattice quantum chromodynamics calculations or the |V_{cs}| from the CKMfitter group, we extract |V_{cs}|=0.978±0.009±0.012 and f_{D_{s}^{+}}=(251.1±2.4±3.0)  MeV, respectively. Combining our result with the world averages of B_{D_{s}^{+}→τ^{+}ν_{τ}} and B_{D_{s}^{+}→μ^{+}ν_{μ}}, we obtain the ratio of the branching fractions B_{D_{s}^{+}→τ^{+}ν_{τ}}/B_{D_{s}^{+}→μ^{+}ν_{μ}}=9.72±0.37, which is consistent with the standard model prediction of lepton flavor universality.

Observation of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e}

Using 2.93  fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at a center-of-mass energy of 3.773 GeV, the observation of the D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} semileptonic decay is presented. The statistical significance of the decay D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is greater than 10σ. The branching fraction of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is measured to be (1.09±0.13_{-0.16}^{+0.09}±0.12)×10^{-3}. Here, the first uncertainty is statistical, the second is systematic, and the third originates from the assumed branching fraction of K_{1}(1270)^{-}→K^{-}π^{+}π^{-}. The fraction of longitudinal polarization in D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is determined for the first time to be 0.50±0.19_{stat}±0.08_{syst}.

Differential Levels of Fatty Acid-Amino Acid Conjugates in the Oral Secretions of Lepidopteran Larvae Account for the Different Profiles of Volatiles

BACKGROUND

Plants have evolved sophisticated defense responses to insect herbivore attack, which often involve elicitors in the insects' oral secretions. The major eliciting compounds in insect oral secretions across different species and their potency in inducing volatile emissions have not yet been fully characterized and compared.

RESULTS

Seven lepidopteran insects with variable duration of association with maize were selected, five species known as pests for a long time (Ostrinia furnacalis, Spodoptera exigua, Spodoptera litura, Mythimna separata, and Helicoverpa armigera) and two newly emerging pests (Athetis lepigone and Athetis dissimilis). Oral secretions of the newly emerging pests have the highest total contents of Fatty Acid-Amino Acid Conjugates (FACs), and their relative composition was well separated from that of the other five species in principal compound analysis. Redundancy analyses suggested that higher quantity of FACs was mainly responsible for the increases in maize volatiles, of which (E)-3,8-dimethyl-1,4,7-nonatriene (DMNT) and (E, E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT) were the most strongly inducible compounds. Adding FACs to the oral secretion of S. litura larvae significantly increased the emissions of TMTT and DMNT, confirming the key role of FACs in inducing volatile emissions in maize plants. Additional experiments with artificial diet spiked with linolenic acid suggested that variation in FACs is due to differences in internal FAC degradation and fatty acid excretion.

CONCLUSION

Compared with two newly emerging pests A. lepigone and A. dissimilis, the long-term pests could diminish the volatile emission by maize through reducing the FAC content in their oral secretions, which may lower the risk of attracting natural enemies.