樟树(Camphora officinarum Nees ex Wall)作为我国南方地区重要的乡土树种和城市绿化骨干树种,其健康生长对生态安全和城市景观至关重要。近年来,由尖孢镰刀菌(Fusarium oxysporum)引起的樟树枯萎病呈现高发态势,因其隐蔽性强、扩散迅...樟树(Camphora officinarum Nees ex Wall)作为我国南方地区重要的乡土树种和城市绿化骨干树种,其健康生长对生态安全和城市景观至关重要。近年来,由尖孢镰刀菌(Fusarium oxysporum)引起的樟树枯萎病呈现高发态势,因其隐蔽性强、扩散迅速、防治困难,已成为威胁樟树生存的最严重病害之一。本文以湖北省黄石市杭州东路香樟为研究对象,通过系统调查和实验分析,深入探讨了尖孢镰刀菌的生物学特性、致病机理及其对樟树的危害症状与诊断方法。在此基础上,结合杭州东路香樟的生长现状和病害特点,提出了一套集“精准诊断、应急处理、生态调控、长效管理”于一体的综合救治体系。研究结果表明,尖孢镰刀菌在杭州东路香樟中的感染率高达14.1%,且病情呈加速蔓延趋势。通过实施以土壤改良为核心,结合化学防治、生物防治和栽培管理的综合措施,可有效控制病害蔓延,恢复树木健康。本研究旨在为城市园林绿化养护部门提供科学依据和技术支持,推动樟树枯萎病的有效防控和可持续管理。展开更多
[Objective]Leaf diseases significantly affect both the yield and quality of tea throughout the year.To address the issue of inadequate segmentation finesse in the current tea spot segmentation models,a novel diagnosis...[Objective]Leaf diseases significantly affect both the yield and quality of tea throughout the year.To address the issue of inadequate segmentation finesse in the current tea spot segmentation models,a novel diagnosis of the severity of tea spots was proposed in this research,designated as MDC-U-Net3+,to enhance segmentation accuracy on the base framework of U-Net3+.[Methods]Multi-scale feature fusion module(MSFFM)was incorporated into the backbone network of U-Net3+to obtain feature information across multiple receptive fields of diseased spots,thereby reducing the loss of features within the encoder.Dual multi-scale attention(DMSA)was incorporated into the skip connection process to mitigate the segmentation boundary ambiguity issue.This integration facilitates the comprehensive fusion of fine-grained and coarse-grained semantic information at full scale.Furthermore,the segmented mask image was subjected to conditional random fields(CRF)to enhance the optimization of the segmentation results[Results and Discussions]The improved model MDC-U-Net3+achieved a mean pixel accuracy(mPA)of 94.92%,accompanied by a mean Intersection over Union(mIoU)ratio of 90.9%.When compared to the mPA and mIoU of U-Net3+,MDC-U-Net3+model showed improvements of 1.85 and 2.12 percentage points,respectively.These results illustrated a more effective segmentation performance than that achieved by other classical semantic segmentation models.[Conclusions]The methodology presented herein could provide data support for automated disease detection and precise medication,consequently reducing the losses associated with tea diseases.展开更多
The ectomycorrhizal fungus Paxillus involutus was inoculated onto tissue-cultures of the hybrid poplar,Populus davidiana×P.bolleana,to evaluate the elemental defense effect to heavy metals copper and cadmium at d...The ectomycorrhizal fungus Paxillus involutus was inoculated onto tissue-cultures of the hybrid poplar,Populus davidiana×P.bolleana,to evaluate the elemental defense effect to heavy metals copper and cadmium at different concentrations by simulating Alternaria alternata fungus infection.The enrichment capacity of Populus davidiana×P.bolleana for Cu and Cd was closely associated with the degree of heavy metal stress.There was a significant positive interaction of applying Cu and Cd and the inoculation with P.involutus on A.alternata leaf blight disease index.The incidence rate and disease index of leaf blight underwent a significant reduction compared with the controls.Similarly,the ratio of the area of disease spot to leaf area,incidence rate,and disease index for Populus davidiana×P.bolleana leaves inoculated with Paxillus involutus(Batsch)Fr.were significantly lower than those of their nonmycorrhizal counterparts.With increasing the degree of Cu and Cd stress,a gradual increase in the average value of the membership function for the incidence rate and disease index was observed,indicating the weakened pathogen's ability to cause infection and the improved resistance of Populus davidiana×P.bolleana to leaf blight disease under Cu and Cd stress.Moreover,superoxide dismutase enzyme activity in Populus davidiana×P.bolleana increased significantly,reaching levels of 411.0 U/g FW and 421.6 U/g FW under Cu and Cd treatments,respectively.These changes in metabolic products and antioxidant enzyme activities suggest that P.involutus may enhance the resistance of Populus davidiana×P.bolleana to the fungus,Alternaria alternata Fr.Keissel under heavy metal stress by modulating these physiological indicators.展开更多
Cryptorhynchus lapathi L.,a globally distributed wood-boring pest,significantly threatens poplar(Populus spp.)and willow(Salix spp.)trees.Entomopathogenic fungi(EPFs),particularly Beauveria bassiana(Bals.-Criv.)Vuilla...Cryptorhynchus lapathi L.,a globally distributed wood-boring pest,significantly threatens poplar(Populus spp.)and willow(Salix spp.)trees.Entomopathogenic fungi(EPFs),particularly Beauveria bassiana(Bals.-Criv.)Vuilla,play a crucial role in integrated pest management because of their broad-spectrum insecticidal properties.This study clarifies the pathogenic mechanisms of B.bassiana CFCC81428 treatment and its oil-based formulation against male and female C.lapathi adults,alongside their impacts on cumulative mortality,enzyme activity and nutrient metabolism.The results indicated that the oil-based formulation significantly enhanced B.bassiana pathogenicity,achieving cumulative mortality rates of 91.7%and 83.8%for male and female adults,respectively,with LT50 values of 7.9 and 8.7 d,markedly outperforming the B.bassiana treatment.Scanning electron microscopy revealed that the oil-based formulation improved spore adhesion to the insects'cuticle,accelerated spore germination and hyphal growth,and significantly improved cuticular penetration efficiency.Within the host,the activities of detoxification enzymes(GST and CarE)were upregulated,whereas the activities of catalase and peroxidase enzymes were suppressed.Superoxide dismutase activity remained elevated throughout most of the observation time points.Polyphenol oxidase activity significantly increased between 24 and120 h postinfection,indicating its critical role in preventing B.bassiana invasion.The infection also triggered substantial shifts in the host's nutrient metabolism,with time-dependent changes observed in carbohydrates,free fatty acids,and soluble proteins.The oil-based formulation exacerbated the depletion of these nutrients,ultimately leading to metabolic collapse.This study indicates that the oil-based formulation optimizes spore germination conditions and accelerates infection,thereby significantly increasing B.bassiana pathogenicity in C.lapathi males,whereas female adults exhibited stronger physiological and metabolic responses,providing new insights for the application of B.bassiana in the biological control of pests.展开更多
Diplodia tip blight,caused by Diplodia sapinea,is a global pine necrotic disease causing heavy economic losses to the pine industry.Chemical control,its main current management,easily induces pathogen resistance and e...Diplodia tip blight,caused by Diplodia sapinea,is a global pine necrotic disease causing heavy economic losses to the pine industry.Chemical control,its main current management,easily induces pathogen resistance and environmental pollution,which biological control avoids.This study investigated juniper essential oil’s efficacy against the disease on Mongolian Scots pine(Pinus sylvestris var.mongolica)and its induced resistance mechanisms via pot experiments,physiological assays(defense enzyme activities,resistant substances)and metabolomic sequencing(secondary metabolites).Results showed varied efficacy:three foliar sprays of 10μL mL^(-1) oil achieved the best control phenylalanine ammonia-lyase(PAL),polyphenol oxidase(82.9%).The 20μL mL^(-1) treatment significantly increased(PPO)activities,and contents of lignin,flavonoids and total phenolics.Metabolomic analysis showed 326 upregulated and 527 downregulated different metabolites in essential oilinduced and pathogen-inoculated pines,compared to 483 upregulated and 277 downregulated metabolites in noninduced but inoculated pines.The differentially expressed metabolites in treated pines were primarily enriched in pathways related to amino acid metabolism and plant secondary metabolite biosynthesis,with notably increased expression levels of ferulic acid,scopoletin,pipecolic acid,D-proline,and DL-arginine.Therefore,juniper essential oil protects against D.sapinea by inducing systemic acquired resistance in Mongolian Scots pine.In conclusion,juniper essential oil controls D.sapinea by inducing systemic acquired resistance(SAR)in Mongolian Scots pine,clarifying the molecular mechanism and supporting biological control of the disease.展开更多
文摘樟树(Camphora officinarum Nees ex Wall)作为我国南方地区重要的乡土树种和城市绿化骨干树种,其健康生长对生态安全和城市景观至关重要。近年来,由尖孢镰刀菌(Fusarium oxysporum)引起的樟树枯萎病呈现高发态势,因其隐蔽性强、扩散迅速、防治困难,已成为威胁樟树生存的最严重病害之一。本文以湖北省黄石市杭州东路香樟为研究对象,通过系统调查和实验分析,深入探讨了尖孢镰刀菌的生物学特性、致病机理及其对樟树的危害症状与诊断方法。在此基础上,结合杭州东路香樟的生长现状和病害特点,提出了一套集“精准诊断、应急处理、生态调控、长效管理”于一体的综合救治体系。研究结果表明,尖孢镰刀菌在杭州东路香樟中的感染率高达14.1%,且病情呈加速蔓延趋势。通过实施以土壤改良为核心,结合化学防治、生物防治和栽培管理的综合措施,可有效控制病害蔓延,恢复树木健康。本研究旨在为城市园林绿化养护部门提供科学依据和技术支持,推动樟树枯萎病的有效防控和可持续管理。
文摘[Objective]Leaf diseases significantly affect both the yield and quality of tea throughout the year.To address the issue of inadequate segmentation finesse in the current tea spot segmentation models,a novel diagnosis of the severity of tea spots was proposed in this research,designated as MDC-U-Net3+,to enhance segmentation accuracy on the base framework of U-Net3+.[Methods]Multi-scale feature fusion module(MSFFM)was incorporated into the backbone network of U-Net3+to obtain feature information across multiple receptive fields of diseased spots,thereby reducing the loss of features within the encoder.Dual multi-scale attention(DMSA)was incorporated into the skip connection process to mitigate the segmentation boundary ambiguity issue.This integration facilitates the comprehensive fusion of fine-grained and coarse-grained semantic information at full scale.Furthermore,the segmented mask image was subjected to conditional random fields(CRF)to enhance the optimization of the segmentation results[Results and Discussions]The improved model MDC-U-Net3+achieved a mean pixel accuracy(mPA)of 94.92%,accompanied by a mean Intersection over Union(mIoU)ratio of 90.9%.When compared to the mPA and mIoU of U-Net3+,MDC-U-Net3+model showed improvements of 1.85 and 2.12 percentage points,respectively.These results illustrated a more effective segmentation performance than that achieved by other classical semantic segmentation models.[Conclusions]The methodology presented herein could provide data support for automated disease detection and precise medication,consequently reducing the losses associated with tea diseases.
基金supported by the National Natural Science Foundation of China(31800542)Natural Science Foundation of Heilongjiang Province(LH2023C105)Heilongjiang Research Institutes Basic Research Funding Project(LKSB2024-9)。
文摘The ectomycorrhizal fungus Paxillus involutus was inoculated onto tissue-cultures of the hybrid poplar,Populus davidiana×P.bolleana,to evaluate the elemental defense effect to heavy metals copper and cadmium at different concentrations by simulating Alternaria alternata fungus infection.The enrichment capacity of Populus davidiana×P.bolleana for Cu and Cd was closely associated with the degree of heavy metal stress.There was a significant positive interaction of applying Cu and Cd and the inoculation with P.involutus on A.alternata leaf blight disease index.The incidence rate and disease index of leaf blight underwent a significant reduction compared with the controls.Similarly,the ratio of the area of disease spot to leaf area,incidence rate,and disease index for Populus davidiana×P.bolleana leaves inoculated with Paxillus involutus(Batsch)Fr.were significantly lower than those of their nonmycorrhizal counterparts.With increasing the degree of Cu and Cd stress,a gradual increase in the average value of the membership function for the incidence rate and disease index was observed,indicating the weakened pathogen's ability to cause infection and the improved resistance of Populus davidiana×P.bolleana to leaf blight disease under Cu and Cd stress.Moreover,superoxide dismutase enzyme activity in Populus davidiana×P.bolleana increased significantly,reaching levels of 411.0 U/g FW and 421.6 U/g FW under Cu and Cd treatments,respectively.These changes in metabolic products and antioxidant enzyme activities suggest that P.involutus may enhance the resistance of Populus davidiana×P.bolleana to the fungus,Alternaria alternata Fr.Keissel under heavy metal stress by modulating these physiological indicators.
基金supported by the“Applied Technology Research and Development Project of Heilongjiang Province(GA20B401-2)”“The Key Research and Development Project of Heilongjiang Province(2023ZX02B05)”。
文摘Cryptorhynchus lapathi L.,a globally distributed wood-boring pest,significantly threatens poplar(Populus spp.)and willow(Salix spp.)trees.Entomopathogenic fungi(EPFs),particularly Beauveria bassiana(Bals.-Criv.)Vuilla,play a crucial role in integrated pest management because of their broad-spectrum insecticidal properties.This study clarifies the pathogenic mechanisms of B.bassiana CFCC81428 treatment and its oil-based formulation against male and female C.lapathi adults,alongside their impacts on cumulative mortality,enzyme activity and nutrient metabolism.The results indicated that the oil-based formulation significantly enhanced B.bassiana pathogenicity,achieving cumulative mortality rates of 91.7%and 83.8%for male and female adults,respectively,with LT50 values of 7.9 and 8.7 d,markedly outperforming the B.bassiana treatment.Scanning electron microscopy revealed that the oil-based formulation improved spore adhesion to the insects'cuticle,accelerated spore germination and hyphal growth,and significantly improved cuticular penetration efficiency.Within the host,the activities of detoxification enzymes(GST and CarE)were upregulated,whereas the activities of catalase and peroxidase enzymes were suppressed.Superoxide dismutase activity remained elevated throughout most of the observation time points.Polyphenol oxidase activity significantly increased between 24 and120 h postinfection,indicating its critical role in preventing B.bassiana invasion.The infection also triggered substantial shifts in the host's nutrient metabolism,with time-dependent changes observed in carbohydrates,free fatty acids,and soluble proteins.The oil-based formulation exacerbated the depletion of these nutrients,ultimately leading to metabolic collapse.This study indicates that the oil-based formulation optimizes spore germination conditions and accelerates infection,thereby significantly increasing B.bassiana pathogenicity in C.lapathi males,whereas female adults exhibited stronger physiological and metabolic responses,providing new insights for the application of B.bassiana in the biological control of pests.
基金supported by the National Key R&D Program of China(2022YFD1401005).
文摘Diplodia tip blight,caused by Diplodia sapinea,is a global pine necrotic disease causing heavy economic losses to the pine industry.Chemical control,its main current management,easily induces pathogen resistance and environmental pollution,which biological control avoids.This study investigated juniper essential oil’s efficacy against the disease on Mongolian Scots pine(Pinus sylvestris var.mongolica)and its induced resistance mechanisms via pot experiments,physiological assays(defense enzyme activities,resistant substances)and metabolomic sequencing(secondary metabolites).Results showed varied efficacy:three foliar sprays of 10μL mL^(-1) oil achieved the best control phenylalanine ammonia-lyase(PAL),polyphenol oxidase(82.9%).The 20μL mL^(-1) treatment significantly increased(PPO)activities,and contents of lignin,flavonoids and total phenolics.Metabolomic analysis showed 326 upregulated and 527 downregulated different metabolites in essential oilinduced and pathogen-inoculated pines,compared to 483 upregulated and 277 downregulated metabolites in noninduced but inoculated pines.The differentially expressed metabolites in treated pines were primarily enriched in pathways related to amino acid metabolism and plant secondary metabolite biosynthesis,with notably increased expression levels of ferulic acid,scopoletin,pipecolic acid,D-proline,and DL-arginine.Therefore,juniper essential oil protects against D.sapinea by inducing systemic acquired resistance in Mongolian Scots pine.In conclusion,juniper essential oil controls D.sapinea by inducing systemic acquired resistance(SAR)in Mongolian Scots pine,clarifying the molecular mechanism and supporting biological control of the disease.
