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This review systematically elucidates the mechanisms of action of forward genetics screening methods, including ultraviolet mutagenesis, chemical mutagenesis, Agrobacterium tumefaciensmediated transformation, and transposon-mediated random insertion mutagenesis, and specifically summarizes their applications in gene function analysis of animal pathogenic fungi, mycotoxin degrada‑tion, and strain improvement. By comparing the advantages and limitations of different techniques, this review reveals the current shortcomings in mutagenesis efficiency, controllability of mutation loci, high-throughput screening systems, as well as the coverage and representativeness of mutant libraries. Future research should focus on developing efficient and targeted mutagenesis techniques, precise screening strategies, and deepend the integration of multi-omics technologies in the phenotypic analy‑sis of mutants. These researches will advance the systematic elucidation of gene functions, enhance the efficient degradation of mycotoxins, and provide robust technical foundation for controlling animal fungal diseases and optimizing industrial and agricultural fungal strains.
【Objective】Verical distribution characteristics and its environmental drivers of the leafeating pest damage in Quercus variabilis forest was investigated in order to provide theoretical reference for developing effective long-term ecological control strategy against forest pest. 【Method】This study selected pure Q. variabilis forests and Q. variabilis-Platycladus orientalis mixed forests in the Qingli‑ang Temple forest area of Dengfeng Forest Farm, Henan Province, as research subjects. Structural equation modeling(SEM) was employed to explore the effects of stand characteristics, understory veg‑etation diversity, and surface features on the damage severity of leaf-eating pests across different forest layers. 【Result】1) The damage severity of leaf-eating pests was significantly higher in mixed forests than in pure forests, with the lower canopy layer exhibiting significantly greater damage than the upper canopy and seedling layers. 2) Pest damage in the upper canopy was primarily regulated by stand char‑acteristics, while the influence of understory plant diversity and surface features gradually increased with the decreasing of the forest layer. 3) Q. variabilis forests with higher biomass provided abundant food resources, favoring the feeding activities of leaf-eating pests. 4) Rich herbaceous plant diversity significantly suppressed the damage caused by Q. variabilis leaf-eating pests. 【Conclusion】In the pre‑vention and control of Q. variabilis leaf-eating pests, enhancing herbaceous layer species diversity and improving the stability and natural defense capacity of Q. variabilis forests are critical strategies for achieving sustainable management of Q. variabilis plantations.
This review summarizes the physicochemical properties, application status, and hazards of quinclorac, and outlines the research progress on microbial degradation of quinclorac, including degrading strains types, degradation mechanisms, key influencing factors, and optimization strate‑gies. Furthermore, the deficiencies in the practical application of microbial degradation of quinclorac are discussed, and the limitations of current research are analyzed in depth. Finally future develop‑ment directions are envisioned to provide a scientific basis for the theoretical exploration and technical practice of bioremediation for quinclorac pollution.
【Objective】To address the low metering accuracy and poor application uniformity of tradi‑tional fluted-wheel fertilizer metering devices, a cell-wheel precision fertilizer meter with dual-variable regulation was proposed.【Method】The device achieves wide-range precision fertilization through the synergistic adjustment of graded cellular number and continuous rotational speed control.The Discrete Element Method was employed to simulate the fertilizer discharge process, with the coefficient of varia‑tion(CV) of fertilizer uniformity as the evaluation index.A three-factor, three-level experiment was conducted for parameter optimization, followed by bench and field tests under the optimal parameter combination.【Result】Simulation and experimental results indicated that the factors influencing fertilizer discharge uniformity ranked, in descending order of significance, as cellular arc radius, cellular volume, and cellular wheel rotational speed.When the cellular volume was 700 mm3, the arc radius was 6.50 mm, and the rotational speed was 47.33 r·min-1, the optimal uniformity CV reached 4.78%.The bench test yielded a CV of 3.11%, confirming the reliability of the optimized parameters.Field experiments showed that the fertilizer rate error ranged from 3.54% to 4.47%, and the uniformity CV ranged from 3.85% to 5.84%, both meeting the national standard requirements(fertilizer rate error ≤5%, and CV ≤7.8%).【Conclusion】The device achieves dynamic and precise control of the fertilizer discharge process through dual-variable regulation, providing a new design approach for structural optimization and intelligent control of precision fertilization equipment.
【Objective】Aiming at the problems of low segmentation accuracy and misjudgment of diseases in potato leaf disease and pest images under complex agricultural production environments, a group normalization-residual Swin Transformer parallel Unet(GSTP-Unet) method was constructed to improve the segmentation accuracy of disease and pest images.【Method】A parallel dual-branch up/downsampling module composed of Swin Transformer modules and improved ResNet modules was designed to obtain the local information extraction capability of convolution and the global information modeling capability of Transformer; A new feature fusion method was proposed to reduce the feature distribution mismatch caused by different normalization methods during dual-branch feature fusion; A multi-scale feature output strategy was introduced to enhance the model's ability to characterize the details of diseases and pests, which can improve the segmentation effect of disease and pest images.【Result】In terms of the two key metrics, mean intersection over union and Dice coefficient, GSTPUnet achieved 83.17% and 90.43%, respectively.Compared with U-Net, Swin-Unet, and Deep‑LabV3(ResNet50), GSTP-Unet improved the mIoU by 6.30%, 6.48%, and 5.24%, respectively, and also maintained a leading position in other metrics.【Conclusion】GSTP-Unet performs better in the segmentation of potato leaf disease and pest images.
【Objective】This study aims to address the problems of low accuracy, computational com‑plexity, and susceptibility to missed and false detection of the existing corn horn detection algorithm model.【Method】A lightweight corn detection model with global feature information fusion is proposed by using YOLOv8n as the baseline.First, the gather and distribute-scale sequence feature fusion(GDS) feature extraction mechanism is introduced to replace the path aggregation network-feature pyramid network structure(PAN-FPN) of the original model neck network.Through the gathering and distributing(GD) module and the scale sequence feature fusion(SSFF) module, the capability of the neck network in extracting and fusing feature information is further enhanced, which can successfully address the issue of feature information attenuation in the traditional PAN-FPN architecture while main‑taining computational efficiency.Second, the C2f module is replaced with the enhanced C2f-RVBEMA composite structure, which is formed by fusing the reparameterized visual transformers feature extraction block(RVB) and the efficient multi-scale attention mechanism(EMA).Through the EMA attention mechanism, pixel-level attention allocation is achieved, which enhances the perception of key regions to improve the detection accuracy of occluded targets, meanwhile, it improves the ability to extract target features, which retains more features of small targets and thus enhances detection accuracy.Finally, the fused Focaler-ShapeIOU is used as a loss function to optimize the localization accuracy and recognition ability to improve the detection performance.【Result】This algorithm improves the mAP@0.5, Precision and Recall on the corn horn datasets by 4.3%, 2.1% and 7.7%, respectively.The amount of parameters is reduced by 3.8×106, and the model volume is compressed to 4.5 MB.【Conclusion】Through the optimization of network structure and loss function, the algo‑rithm improves the detection accuracy while realizing the model lightweight, which provides an effi‑cient visual support for accurate spraying of corn horn.
【Objective】To overcome the poor water solubility of the veterinary drug rafoxanide(RFN), and to enhance its application effectiveness and operational convenience in intensive farming systems.【Method】First, novel rafoxanide nanoparticles(RFN-NPs) were prepared using monomethoxy polyeth‑ylene glycol-polylactic acid-glycolic acid copolymer(mPEG-PLGA) as the carrier.Using particle size, polydispersity index(PDI), encapsulation efficiency, and drug loading capacity as evaluation indicators, the effects of the organic solvent volume ratio(acetone/dichloromethane), polyvinyl alco‑hol(PVA) mass fraction, oil-to-water phase volume ratio, carrier mass fraction, and RFN mass on RFN-NPs preparation were investigated through single-factor experiments.Combined with response surface methodology, the preparation process of the novel RFN-NPs was optimized.Subsequently, lyophilization technology was applied to convert the nanoparticles into a nano lyophilized powder(here‑inafter referred to as the lyophilized powder) and the safety of lyophilized powder was characterized and evaluated.Morphological and structural characterization was performed using transmission elec‑tron microscopy(TEM), Fourier transform infrared spectroscopy(FTIR), and X-ray diffraction(XRD).Stability was characterized through in vitro release tests and stability studies.Safety evalua‑tion was conducted both in vitro and in vivo, including biochemical parameter analysis, histopathologi‑cal examination, and hemolysis assays.【Result】 The optimized preparation process is as follows: organic solvent volume ratio of 1∶2, polyvinyl alcohol mass fraction of 1%, oil-to-water phase volume ratio of 2∶3, carrier mass fraction of 3%, RFN mass of 20 mg, and ultrasonication time of 5 min, and RFN-NPs had a particle size of 256.6 nm, a polydispersity index of 0.082, an encapsulation effi‑ciency of 96.48%, and a drug loading capacity of 17.07%.After lyophilization, the reconstituted lyophilized powder exhibited high dispersion and a distinct Tyndall effect.The prepared lyophilized powder appeared fluffy with a granular texture.Transmission electron microscopy(TEM) revealed that the particles of the lyophilized powder displayed a relatively regular spherical structure with smooth edges and no significant agglomeration.Fourier transform infrared spectroscopy(FTIR) and X-ray dif‑fraction(XRD) confirmed that RFN was successfully encapsulated into the carrier and integrated with the carrier material.in vitro, the lyophilized powder released the drug slowly under different pH condi‑tions.The fastest release rate was observed in a medium with a pH of 6.8, where the cumulative release reached 44.17% at 72 hours.After storage at 4 or 25 ℃ for 30 days, the reconstituted lyophi‑lized powder showed no significant changes in particle size or PDI, indicating good stability.The lyophilized powder was administered intraperitoneally to mice at doses of 20, 40, and 80 mg·kg-1 once daily for 7 consecutive days.Necropsy results showed that the morphological structures and histopatho‑logical sections of organs such as the heart, liver, spleen, lungs, and kidneys in all dose groups showed no significant differences compared with the negative control group.Biochemical indicators fur‑ther confirmed no significant alterations in liver or kidney function.Additionally, the lyophilized powder did not induce hemolysis of red blood cells.【Conclusion】The novel RFN-NPs lyophilized powder was successfully prepared.This lyophilized powder exhibits uniform particle size, high stability, no hemolytic effect on red blood cells, and excellent safety.
【Objective】This study identified potential RNA silencing suppressors and elucidated their functions in the pathogenicity of Fusarium pseudograminearum, thereby uncovering the molecular mechanisms underlying the interaction between this pathogen and its host. 【Method】Potential RNA silencing suppressors were screened by co-expressing candidate effectors with GFP(green fluorescent protein) in 16C transgenic tobacco. Their protein structures were analyzed using bioinformatics approaches, and the secretory function of their signal peptides was validated through a yeast secretion system. The impact of the RNA silencing suppressor on pathogen infection was assessed by inoculating pathogens onto tobacco leaves expressing the candidate effector. Additionally, the pathogenicity of knockout mutants was determined after deleting the FpPLA gene via homologous recombination. 【Result】First, strong green fluorescence signals were exclusively detected in 16C tobacco leaves coinfiltrated with FpPLA(F. pseudograminearum Phospholipase A) and GFP gene, indicating that FpPLA expression suppresses the plant's RNA silencing pathway. Second, FpPLA protein was experi‑mentally confirmed as a secretory protein, and its expression in plants can inhibit plant pathogen infec‑tion. Finally, knockout of the FpPLA gene did not significantly affect virulence on wheat coleoptiles compared to the wild-type strain WZ-8A. 【Conclusion】During wheat infection by F. pseudograminearum, the effector protein FpPLA is secreted into plant cells, where it inhibits the plant RNA silencing pathway to suppress the pathogen infection process. However, knocking out the single FpPLA gene has no impact on the pathogenicity of F. pseudograminearum.
【Objective】To screen salt-alkali tolerant plant growth-promoting rhizobacteria(PGPR) with growth-promoting capabilities, so as to provide a theoretical basis and bacterial resources for the improvement of saline-alkali soils and the development of microbial fertilizers.【Method】Rhizosphere soil samples of peanut plants were collected from Hami, Xinjiang Uygur Autonomous Region, and bac‑teria were isolated and screened using Luria-Bertani(LB) medium.Based on morphological characteristics, physiological and biochemical properties, and 16S rRNA gene sequence analysis, the target strain was identified.The growth capacity of the target strain was evaluated under varying NaCl concen‑trations(0-200 g·L-1), temperatures(5-55 ℃), and pH levels(4-13) to determine its salt tolerance range, temperature tolerance, and pH tolerance.The multiple functional identification media were used to assess the plant growth-promoting functions, including amylase production, siderophore syn‑thesis, and cellulase production.Additionally, the capacity for amylase production and biofilm forma‑tion was quantitatively determined.Through plate and pot experiments, the growth-promoting effects on tomato and maize seedlings were evaluated, respectively.【Result】A bacterial strain was isolated and identified as Bacillus halotolerans, designated as Bacillus halotolerans ZP-3821.Strain ZP-3821 was capable of growing within a NaCl concentration range of 0-40 g·L-1, a temperature range of 20-50 ℃, and a pH range of 5-10.The strain exhibited the abilities of fixing nitrogen, producing amy‑lase, synthesizing siderophores, secreting cellulase, and forming biofilm.The plate experiment results showed that strain ZP-3821 significantly enhanced the aboveground fresh weight, underground fresh weight, and lateral roots number of tomato seedlings under saline-alkali stress.Under the condi‑tion of pH value 8.0+2.0 mmol·L-1 NaHCO_3+0 mmol·L-1 NaCl, compared with the control group, inoculation with ZP-3821 increased the aboveground fresh weight, underground fresh weight, and lateral roots number by 169.04%, 198.37%, and 509.48%, respectively.Pot experiment results indi‑cated that under salt stress with a NaCl concentration of 6 g·kg-1, compared to the control, inoculation with strain ZP-3821 increased the underground fresh weight and total fresh weight of maize seedlings by 39.82% and 18.65%, respectively.【Conclusion】Bacillus halotolerans ZP-3821 exhibits excellent salt-alkali tolerance and can promote plant growth under salt-stressed conditions.
【Objective】This study was designed to evaluate the application potential of the plant growth-promoting rhizosphere fungus Penicillium PQxj3(hereinafter referred to as the growthpromoting strain PQxj3), thereby providing technical support for the development of efficient and green agricultural biological agents.【Method】Using the viable count as the indicator, single-factor experiments were designed with the liquid-to-solid ratio [V(H_2O/mL)∶m(bran/g)], temperature, incubation time, and inoculation mass fraction as influencing factors.Based on these results, the fer‑mentation conditions of strain PQxj3 were further optimized using response surface methodology(RSM).A tobacco pot experiment was conducted to compare the PQxj3 agent along with three com‑mercial microbial agents(a compound microbial agent, a Trichoderma harzianum agent, and a Delong PeiGen agent) by measuring fresh weight and root weight, thereby demonstrating its growth-promoting advantage.Furthermore, pot experiments on nine different crops(spinach, Shanghai pak choi, cucum‑ber, mustard, cabbage, sesame, endive, onion, and fast-growing Chinese cabbage) were conducted to systematically analyze the broad-spectrum growth-promoting capability of the PQxj3 agent.【Result】The optimal solid-state fermentation conditions for strain PQxj3 were determined as follows: liquid-tosolid ratio of 92.9∶100.0, temperature of 22.8 ℃, incubation time of 15 days, and inoculation mass fraction of 2.5%.Under these conditions, the viable count reached 2.6×109 cfu·g-1.The PQxj3 agent prepared under these optimized conditions increased the fresh weight and root weight of tobacco by 2.17 times and 4.29 times compared to the blank control group, respectively, significantly outperform‑ing the commercial agents.The PQxj3 agent also significantly promoted the growth of spinach, Shang‑hai pak choi, cucumber, mustard, cabbage, sesame, endive, onion, and fast-growing Chinese cab‑bage, with the fresh weight of each treatment group increasing by 100.94%, 138.45%, 71.53%, 178.53%, 115.33%, 140.90%, 257.75%, 46.23%, and 170.30%, respectively, compared with the blank control group.【Conclusion】After optimization of the fermentation process, the PQxj3 agent exhibits significant advantages in plant growth promotion and broad-spectrum applicability.