With climate change, global temperatures are expected to rise, posing a pervasive and growing threat to biodiversity and ecosystem stability. As ectotherms, insects are completely dependent on environmental temperature to grow, develop, and regulate various physiological functions. Therefore, global warming is likely to have direct or indirect effects on insect individuals, populations, and their associated communities and food webs. However, many studies have suggested that the species at higher trophic levels seem to be more sensitive to changes in environmental factors, meaning that predators and parasitoids may face more severe challenges than their prey or hosts. In this paper, we analyzed the effects of temperature changes on the development, reproduction, predation and parasitism of insect natural enemies based on existing studies, compared the responses of the same species (different natural enemy species) and different trophic level species (natural enemy and its host or prey) to temperature increase, and summarized the synchronicity changes between natural enemies and pests caused by global warming. Understanding the response of insect predators and parasitoids to temperature rise is of great significance for biological control and ecological governance of agricultural pests in a warming climate.

Cucumber green mottle mosaic virus (CGMMV) is widely distributed in the world. It mainly infects cucurbitaceous crops, causing serious damage and incalculable economic loss to the commercial planting and production of cucurbitaceous crops. This paper analyzed the main factors affecting the rapid spread and epidemic of CGMMV, summarized the prevention and control strategies of CGMMV in epidemic areas focusing on seed disinfection and non-epidemic areas focusing on prevention of transmission, introduced the main detection methods of CGMMV, such as serology and molecular biology, compared the advantages and disadvantages of various existing control methods, and looked forward to the application prospect of new antiviral agents and genetic engineering technologies in the control of CGMMV.

Soil moisture is a sensitive factor for crop phenological growth, climate and environment changes, and it plays an important role in the land surface water and atmospheric circulation. In this paper, the soil moisture retrieval algorithms based on active microwave remote sensing, passive microwave remote sensing and Global Navigation Satellite System Reflectometry (GNSS-R) technology were firstly sorted, including: 1) active microwave remote sensing-based empirical model, semiempirical model, physical scattering model for bare ground surface, and water cloud model (WCM), Michigan microwave canopy scattering (MIMICS) model for vegetation coverage; 2) passive microwave remote sensing-based Q/H, H_p, Q_p roughness models for bare ground surface and \tau-\omega model for vegetation coverage; 3) spaceborne and ground-based GNSS-R soil moisture retrieval algorithms. Secondly, the research and development of soil moisture retrieval from microwave remote sensing in recent decades were reviewed. It was proposed that the key to improve the accuracy of soil moisture retrieval was to quantify accurately the spatial and temporal variability of soil moisture retrieval factors such as vegetation and surface roughness, especially the uncertainty of vegetation growth process and the resulting electromagnetic wave radiation transmission mechanism. Finally, the application outlook of soil moisture in agricultural production and land-surface moisture circulation was prospected, and it was pointed out that the response and feedback mechanism of soil moisture on global scale to climate change would be a research hotspot in the future.

In order to evaluate systematically the biological functions of outer membrane proteins (OMPs) under environmental stresses, we selected Aeromonas hydrophila ATCC 7966 as the research object, and constructed 33 OMP deletion strains to determine their growth status under the stress conditions of osmotic pressure, metal ions, H₂O₂ and pH. The results showed that the AHA_0461 and AHA_4275 (encoding TonB protein family) knockout strains grew better than the wild type strain under the osmotic pressure stress. The AHA_2282 (encoding an unknown functional protein) knockout strain grew weakly under the metal ion stresses, while ΔAHA_0904 strain grew better under the osmotic pressure stress. The AHA_2145 (encoding long-chain fatty acid transporter) knockout strain grew weakly under the H₂O₂ and metal ion stresses. The growth of AHA_1279, AHA_1281 (encoding OmpA family protein)and pilQ, AHA_0569 (encoding secretin family protein) knockout strains was weaker than the wild type strain under the H₂O₂ stress. It was suggested that these OMPs may play important roles in response to environmental stresses. These results may highlight a comprehensive understanding of the physiological functions of bacterial OMPs under different environmental stresses in the future, and provide possible targets for the prevention and control of this pathogen.

This study attempted to explore the effects of maize plant type and row width on the light environment, chlorophyll content, photosynthetic performance, growth characteristics and yield of ginger under the maize/ginger intercropping mode. A total of eight treatments were set, including two plant types of maize cultivars [expanded cultivar ‘Zhenghong 311’ (ZH 311), and compact cultivar ‘Zhenghong 2’ (ZH 2)], three row widths (2, 3, and 4 m), and two controls (sole cropping of ginger under shading, CK₁; sole cropping of ginger without shading, CK₂). The results indicated that shading could increase the chlorophyll content of leaves, maintain a low chlorophyll (Chl) a/b ratio, improve the photosynthetic performance of ginger leaves, so as to promote the growth of plant height, stem diameter and branching number, and obtain a high yield. The plant height, stem diameter, branching number, yield, contents of Chl a, Chl b, total chlorophyll and carotenoid, total chlorophyll/carotenoid ratio, net photosynthetic rate, stomatal conductance, and transpiration rate of ginger under the maize/ginger intercropping mode were higher than those of CK₂, while the light transmittance of ginger canopy and bottom, Chl a/b ratio, and intercellular CO₂ concentration were lower than those of CK₂. In summary, the shading effects of maize/ginger intercropping on ginger are significantly different in maize plant type and row width. The expanded maize cultivar with 2 m row width has the best shading effect on ginger.

The objective of this study was to establish the optimum enzymolysis technology for Portunus trituberculatus seasoning based on the cooking liquor. Taking the flavor amino acid contents as evaluation indicators, a two-step enzymolysis technology with alcalase and flavorzyme was determined by response surface optimization methodology, and volatile flavor compounds in the secondary enzymolysis liquor were qualitatively and quantitatively analyzed by headspace-solid phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS). The results indicated that the optimum technological conditions of the primary enzymolysis were alcalase of 6 825 U/g, primary hydrolysis pH 8.45, hydrolysis time of 2.50 h, and the content of flavor amino acid in the hydrolysate was (7.18±0.09) mg/mL. The optimum technological conditions of the secondary enzymolysis were flavorzyme of 3 750 U/g, primary hydrolysis pH 6.81, hydrolysis time of 3.33 h, and the content of flavor amino acid in flavor precursors of P. trituberculatus seasoning was (10.49±0.12) mg/mL, which was 135.2% higher than that of P. trituberculatus cooking liquor. There were 62 volatile flavor compounds in the secondary hydrolysate; among them, hexanal, benzaldehyde and unsaturated alcohol were the main flavor components.The results provide a theoretical basis for the research of seasoning products of cooking liquor and high value utilization of P. trituberculatus.

A method for simultaneous extraction, purification, and determination of persistent organic pollutants (POPs) in soil, such as polychlorinated biphenyls, polybrominated diphenyl ethers, and polycyclic aromatic hydrocarbons, was developed in this study. The optimum conditions for extraction and purification were as follows: Soil samples were extracted ultrasonically three times with acetone/n-hexane (1∶?1, by volume), followed by purification with Florisil solid-phase extraction column, and eluted by 12 mL of n-hexane/dichloromethane (9∶1, by volume) mixture solution. The eluant was concentrated by gentle N₂ streams and finally quantified by gas chromatography-mass spectrometry (GC-MS) with PCB209 as the internal standard. Except for 2, 2′, 3, 3′, 4, 4′, 5, 5′, 6, 6′-decabromodiphenyl ether (BDE209), the other 41 POPs were efficiently separated within 23.83 min. Excellent linearity was observed in the concentration range of 20-1 000 μg/L for all POPs with the coefficients of determination (R²) of 0.997 5-0.999 9. The detection limits of 42 POPs were 0.04-1.19 ng/g, and the spiked recoveries ranged from 71.04% to 120.89% with relative standard deviations of 0.88%-6.29%, and intra- and inter-day reproducibility variations were less than 11%. In conclusion, this method greatly reduces time and workload and is characterized by simple operation, good accuracy, and high sensitivity. It can be widely applied to the determination and analysis of POPs in soil, such as e-waste disposal site soil, which will facilitate further studies on the fate and risk assessment of POPs.

To study the degradation of hexachlorobenzene (HCB) in contaminated soil by dielectric barrier discharge (DBD), a fluidized-bed DBD reactor was used to degrade HCB in contaminated soil. The results showed that a discharge current pulse could be generated with a 20 μs pulse width. When the air flow rate was 4.0 L/min, the soil reached a fully fluidized state. The energy density of reactor increased with the increase of discharge voltage, which promoted HCB degradation, but increasing heating led to lower energy utilization. The HCB degradation rate reached 97.3% after 32 min while the energy density was 172.5 J/L at a discharge voltage of 16 kV. The neutral or alkaline condition was more beneficial to HCB degradation than the acidic condition. With the increase in the initial HCB concentration, the degradation rate of HCB decreased, but the absolute degradation amount increased. The degradation of HCB conformed to first-order kinetic equation. During the discharge process, the C—Cl bond was attacked by active substances, and low-substituted chlorobenzene and small molecular organic acids and other byproducts were generated, which indicated that the degradation of HCB in contaminated soil was mainly a dechlorination process. The research results have important practical significance for the remediation of actual contaminated soil.

In the case of soil cadmium (Cd) pollution becoming more and more serious, the modified in-situ fixation method is widely used as one of the remediation methods of soil heavy metal pollution. To explore the remediation effects of mixed amendment M (the mass ratio of lime, zeolite, calcium-magnesia phosphate fertilizer and biochar was 71:23∶5∶1) on Cd-contaminated farmland soil, a two-year field experiment was conducted to study the effects of applying 0.1% (MR1), 0.2% (MR2), 0.5% (MR3) of the mixed amendment and 0.5% lime (LM) on the soil and crops, taking no application of the mixed amendment as a control (CK). The results showed that the mixed amendment reduced the bioavailability of Cd in soil mainly by increasing soil pH. Three kinds of addition of the mixed amendment (MR1, MR2, MR3) could maintain or increase the yield of crops and significantly reduce the content of Cd in rice straw and grain. Compared with the CK, the Cd content in rice straw treated by MR1, MR2, MR3 and LM decreased by 11.9%, 10.7%, 20.5% and 19.5%, respectively; and the Cd content in rice grains decreased by 42.9%, 57.1%, 71.4% and 72.1%, respectively. The Cd contents in rice grains under the all treatments were lower than 0.2 mg/kg, which met the food safety standard. Moreover, the mixed amendment could reduce the Cd uptake and transport capacity and grain bioaccumulation coefficient of rice. The results of phospholipid fatty acid analysis showed that the different application levels of mix amendment could increase the soil bacteria amount and the soil microbial community diversity. Compared with the LM, the number of bacteria in the MR2 treatment increased by 43.6%, and the number of Gram-positive bacteria in the MR3 treatment increased significantly to 56.5 nmol/g. In general, compared with the single application of lime, 0.2% of mixed amendment has few effects on soil physical and chemical properties, and increases the number and diversity of soil microbial communities, indicating that it can be used for the remediation of farmland soil Cd pollution while maintaining soil ecological health.

Atrazine (ATZ) is one of the most popular herbicides, and the pollution of atrazine to surface water and groundwater has aroused people’s concern, which is urgent to research and develop water purification technology to deal with it. Boron-doped diamond (BDD) electrode has the advantage of highly efficient production of ·OH, but the degradation of organic pollutant is seriously limited because the ·OH is trapped on the surface of the electrode. In this study, BDD electrode modified by polytetrafluoroethylene (PTFE) improved the degradation efficiency of ATZ. In NaCl solution, after modification with 5.0%, 8.6% and 20.0% PTFE dispersions, the quasi-first order kinetic constants of ATZ degradation reaction were improved by 98.9%, 88.2% and 78.6%, respectively. In NaHCO₃ and Na₂SO₄ solutions, after modification with 8.6% PTFE dispersion, the quasi-first order kinetic constants of ATZ degradation reaction were improved by 49.2% and 127.0%. The PTFE was coated on the surface of BDD electrode in the form of film, which was beneficial to the improvement of the current. Meanwhile, the bubbles that adhered to the surface of BDD were conducive to the formation of ·OH and diffusion of ·OH into the homogeneous solution. The concentration of ·OH in the solution bulk increased by 17.73, 19.89 and 18.81 times after the modification of 5.0%, 8.6% and 20.0 % PTFEs, respectively, and the degradation efficiency of ATZ and removal effect were significantly enhanced. The main ways of ATZ degradation by PTFE modified BDD electrode were dealkylation, dechlorination-hydroxylation and alkyl oxidation reactions.

The purpose of this study was to elucidate how iron-depleted and iron-saturated forms of lactoferrin (Lf) exert its antibacterial activity in vitro. Bacteria were divided into three groups by treated with different forms of porcine Lf: the control group (without addition of Lf), apolactoferrin (Apo-Lf, iron saturation is 6.9%) group and hololactoferrin (Holo-Lf, iron saturation is 100.0%) group. The results showed that: 1) Native Lf and Apo-Lf significantly inhibited the growth of Escherichia coli K88 and Staphylococcus aureus (P＜0.01), which was not observed in Holo-Lf group. 2) Apo-Lf exerted antibacterial effect by chelating iron, and iron supplementation could eliminate the inhibitory effect of Apo-Lf on E. coli K88. 3) Scanning electron microscope (SEM) results revealed that Apo-Lf damaged the surface membranes of E. coli K88 and S. Aureus. However, Holo-Lf showed no effect on all of tested bacteria. 4) Predicted three-dimensional structures showed that the structures of Apo-Lf and Holo-Lf were markedly different, and the active site of Apo-Lf was more likely to directly interact with bacteria. Taken together, Apo-Lf inhibited the growth of E. coli K88 and S. Aureus by chelating iron or destroying the surface of bacteria.

The aim of this study was to investigate the effect of intranasal adjuvant B subunit of heat-labile enterotoxin (LTB) of the recombinant Escherichia coli in combination with ginsenoside Rg1 in mice and evaluate its biological safety profile. Mice were intranasally immunized with saline, inactivated vaccine of porcine reproductive and respiratory syndrome virus (PRRSV), inactivated vaccine of PRRSV admixed with LTB or Rg1 or LTB-Rg1 for three times, respectively. Immunoglobulin M (IgM), IgG and IgA antibody levels in serum and bronchoalveolar mucus were measured by enzyme-linked immunosorbent assay; mRNA expression levels of cytokines from spleen and lung were detected by real-time fluorescent quantitative polymerase chain reation; body mass and serum biochemical indexes of mice were monitored regularly. The results showed that LTB-Rg1 quickly increased the levels of PRRSV-specific IgM, IgG and IgA antibodies in serum and bronchoalveolar mucosa, prolonged antibody functioning time, and remarkably upregulated the expression levels of Th1?- and Th2-type cytokines when compared with the vaccine alone group. LTB-Rg1 had no effects on body mass, hepatic or renal functions. Therefore, LTB-Rg1 is a safe and potential nasal mucosal immune adjuvant that is worthy of further study.

To develop an efficient method for quantifying tobacco plant types in the field, the three-dimensional (3D) point clouds of individual plant of five tobacco cultivars were reconstructed based on multi-view image sequences using the structure from motion method. According to the plant type characteristic indexes commonly used, ten phenotypic parameters such as plant height, top width, bottom width, and maximum width of leaf layer were automatically extracted based on the 3D point cloud of tobacco plant, and the calculation accuracy was evaluated based on the plant height and maximum width of leaf layer measured manually in situ in the field. The results indicated the coefficients of determination (R²) of the plant height and maximum width of leaf layer extracted from the 3D point cloud were all greater than 0.97, and the root mean square errors were 3.0, 3.1 cm, respectively. Meanwhile, the extracted phenotypic parameters of tobacco plants were analyzed by different methods. The results of intergroup correlation analysis showed that 16 pairs of traits were extremely significant positive correlations, while one pair of traits was extremely significant negative correlation. The results of one-way multivariate analysis of variance showed that there were highly significant differences among the plant types. The first three principal components were extracted by principal component analysis, and their cumulative contribution rate to the overall variance was 81.6%. The accuracy of plant type discrimination was 93.7% using Stacking ensemble learning method, which was significantly higher than those using random forest, support vector machine and naive Bayesian. This study can provide a method basis for phenotypic characteristics and plant type recognition of field-grown tobacco plants.