Analysis of Influencing Factors of Pine Wood Nematode Disease in Lu an City Based on GIS

[Objectives]The paper was to figure out the distribution of Monochamus alternatus in the stumps of pine wood nematode infected wood in Lu'an City and to provide a theoretical and practical basis for differentiated prevention and control of pine wood nematode disease in the future.[Methods]The factors influencing the number of epidemic small classes and infected plants in all counties and districts of Lu'an City were analyzed by GIS method,and the number of worms and wormholes of M.alternatus inside and outside the stumps of pine wood nematode infected wood in Lu'an City were investigated on the spot.[Results]There were 98,40,54,781,193,268 and 34 epidemic small classes of pine wood nematode disease,and 7241,6099,9532,39161,11079,49876 and 4853 infected plants in Yu'an District,Jin'an District,Yeji District,Shucheng County,Huoshan County,Jinzhai County and Huoqiu County,respectively.Pine wood nematode disease in Lu'an City mostly occurred in Huoshan County,Shucheng County and Jinzhai County,with relatively high altitude,paddy soil,the annual precipitation higher than 2062 mm,and the annual average temperature lower than 16.2℃.The number of diseased plants of pine wood nematode disease was positively correlated with altitude and annual precipitation,and was negatively correlated with annual average temperature.The number of worms and wormholes in pine wood nematode infected wood was very small at different altitudes,stump heights and stump diameters.[Conclusions]The pine wood nematode infected wood can be differentially processed after stump treatment,and stumps can be peeled.The results will provide a theoretical and practical basis for differentiated prevention and control of pine wood nematode disease in the future.

Study on Sweet Potato Stem Nematode Disease

The pathogen and characteristics, infection cycle, occurrence regularity and damage symptoms of sweet potato stem nematode disease were introduced in the paper. Moreover, the comprehensive prevention measures were put forward, including plant quarantine, agricultural control and chemical control. The study provided certain basis for reducing damages of sweet potato stem nematode disease and improving yield and quality of sweet potato.

A spatio-temporal multi-scale fusion algorithm for pine wood nematode disease tree detection

Pine wood nematode infection is a devastating disease.Unmanned aerial vehicle(UAV)remote sensing enables timely and precise monitoring.However,UAV aerial images are challenged by small target size and complex sur-face backgrounds which hinder their effectiveness in moni-toring.To address these challenges,based on the analysis and optimization of UAV remote sensing images,this study developed a spatio-temporal multi-scale fusion algorithm for disease detection.The multi-head,self-attention mechanism is incorporated to address the issue of excessive features generated by complex surface backgrounds in UAV images.This enables adaptive feature control to suppress redundant information and boost the model’s feature extraction capa-bilities.The SPD-Conv module was introduced to address the problem of loss of small target feature information dur-ing feature extraction,enhancing the preservation of key features.Additionally,the gather-and-distribute mechanism was implemented to augment the model’s multi-scale feature fusion capacity,preventing the loss of local details during fusion and enriching small target feature information.This study established a dataset of pine wood nematode disease in the Huangshan area using DJI(DJ-Innovations)UAVs.The results show that the accuracy of the proposed model with spatio-temporal multi-scale fusion reached 78.5%,6.6%higher than that of the benchmark model.Building upon the timeliness and flexibility of UAV remote sensing,the pro-posed model effectively addressed the challenges of detect-ing small and medium-size targets in complex backgrounds,thereby enhancing the detection efficiency for pine wood nematode disease.This facilitates early preemptive preser-vation of diseased trees,augments the overall monitoring proficiency of pine wood nematode diseases,and supplies technical aid for proficient monitoring.

Microbial inoculants and garbage fermentation liquid reduced root-knot nematode disease and As uptake in Panax quinquefolium cultivation by modulating rhizosphere microbiota community

Objective:To find a suitable ecological cultivation measure to solve the problem of root-knot nematode disease of Panax quinquefolium(Panacis Quinquefolii Radix)and the heavy metals accumulating in its roots.Methods:Three-year-old P.quinquefolium was treated with four different combinations of microbial inoculant(MI)and garbage fermentation liquid(GFL)[the joint application of‘TuXiu’MI and Fifty potassium MI(TF),the combination use of‘No.1'MI and Fifty potassium MI(NF),‘Gulefeng’poly-γ-glutamic acid MI(PGA),GFL],and the untreated control(CK).Here,high-throughput sequencing,ICP-MS and UPLC were employed to systematically characterize changes of microbial diversity and structure composition,heavy metals(As,Cd and Pb)content and ginsenoside content among different treatments.Results:The results revealed that different MIs and GFL could increase the root dry weight of P.quinquefolium,PGA enhanced it by 83.24%,followed by GFL(49.93%),meanwhile,PGA and GFL were able to lessen root-knot nematode disease incidence by 57.25%and 64.35%.The treatment of PGA and GFL can also effectively reduce heavy metals in roots.The As content in GFL and PGA was decreased by 52.17%and 43.48%respectively,while the Cd and Pb contents of GFL and PGA was decreased somewhat.Additionally,the content of total ginsenosides was increased by 42.14%and 42.07%,in response to TF and NF,respectively.Our metagenomic analysis showed that the relative abundance of particular soil microbial community members related to the biocontrol of root-knot nematode disease and plant pathogen(i.e.,Chaetomium in NF,Xylari in GFL,and Microascus in PGA),heavy metal bioremediation(Hyphomacrobium in PGA and Xylaria in GFL),and nitrogen fixation(Nordella and Nitrospira in TF)was significantly increased;notably,potential harmful microflora,such as Plectosaphaerella and Rhizobacter,were more abundant in the control group.Conclusion:MI and GFL could improve the quality of P.quinquefolium by modifying its rhizosphere microbial community structure and composition,both of them are beneficial to the development of ecological cultivation of P.quinquefolium.

Review of Pathogen Identification and Diagnosis Technology of Pinewood Nematode Disease

This article briefly introduced the disease incidence and disservice situation in China. The disease is regarded as cancer in pines for its higher spread and death speed and the difficulty in prevention. Strict quarantine is the main measure on countrol of the disease, for there are many difficulties in the prevention. The most important part of the disease study is the early diagnosis and detection.

Control of Bursaphelenchus xylophilus in the State-owned Sishibacao Forest Farm of Yunyang County,China

In view of the fact that pine wood nematode disease is the most dominant disease in Pinus massoniana forests,which has the characteristics of strong infectivity,fast transmission speed,and great difficulty in prevention and control,a brief description was made to the occurrence status of pine wood nematode disease and difficulties faced with its control in the State-owned Sishibacao Forest Farm of Yunyang County,China,followed by the analysis on the prevention and control measures from aspects of strict control,epidemic situation monitoring,joint prevention and control,and clearance of infected trees,as well as the existing problems of pine wood nematode disease.Finally,reasonable suggestions including strengthening the construction of talent team were put forward,aiming to provide a beneficial reference for the scientific,efficient,and reasonable control of pine wood nematode disease in Pinus massoniana Lamb.forests of Yunyang State-owned Sishibacao Forest Farm.

Effect of Pleurotus ostreatus on Dynamics of Meloidogyne arenaria Population and Control Effectiveness

The control effects and application methods of Pleurotus ostreatus on the peanut root-knot nematode disease, Meloidogyne arenaria, were systematically studied in the greenhouse. Results of pot experiments showed that P. ostreatus could effectively reduce the 2nd-instar population density in the soil, and the larva reduced by 80% compared with the control. P. ostreatus could markedly lower the infecting number of the peanut root-knot nematodes, the nematode density inside the root knots declined by 40.00% -82.64%, and the peanut root knots also reduced by 86.96% - 94. 03%. The fungus could defer the initial infection of M. arenaria to the roots, the epidemic rate of the peanut root-knot nematode disease was significantly cut down, and the increase of root-knot changed from the way of Logistic curve in the control to the way of linear curve in the treatment. The final control effectiveness was about 80%. The results of pot trial also indicated that the control effectiveness is closely related to the application time and the amount of this fungus. The key factor affecting control effectiveness was the application time of P. ostreatus in the soil and the suitable time was 20 days before sowing.