Resistance analysis of the rice variety Huaidao 5 against root-knot nematode Meloidogyne graminicola

Meloidogyne graminicola has emerged as one of the most destructive plant-parasitic nematodes affecting rice(Oryza sativa)production worldwide.Resistance to M.graminicola in rice could be the most effective option for its management.However,sources of germplasm with resistance to M.graminicola in rice remain limited.Here,we describe the root attraction,gall formation and genetic analysis of the resistance to M.graminicola in the rice variety Huidao 5.A nematode attraction assay showed that second-stage juveniles(J2s)of M.graminicola were attracted at the root tip of Huaidao 5 within 8 h without a significant reduction in attraction compared to the susceptible rice variety Nanjing 9108.Microscopic observation of the infection revealed that the J2s invaded root tissues 12 h after inoculation,but their subsequent movement to the root tip was hindered in Huaidao 5,resulting in decreased nematode number compared to Nanjing 9108.Additionally,we used the soil and hydroponic culture systems to simulate upland and flooding conditions in the paddy fields respectively,and found that gall number was significantly reduced,and nematode development was clearly suppressed in Huaidao 5.To investigate the genetic basis of this resistance,cross breeding was performed between the Huaidao 5 and Nanjing 9108 varieties.There was no reduction in the resistance of the F_(1) offspring to M.graminicola in the greenhouse or field trials,suggesting that a dominant gene could control resistance in Huaidao 5.In summary,this study provides a detailed characterization of a novel source of resistance to M.graminicola in rice,which is of great potential for use in crop breeding.

2021—2023年邹城市土源性线虫病监测结果分析

目的:了解邹城市土源性线虫病感染现状,掌握其流行规律及影响因素,为相关部门制定防治策略提供科学依据。方法:2021—2023年选取邹城市常住居民3165人作为研究对象,每年收集常住居民的粪便样本,采用改良加藤厚涂片法检验。结果:在3165名常住居民中,检出土源性线虫病感染16人,总感染率为0.51%,其中鞭虫、蛔虫和蛲虫感染率分别为0.03%、0.03%和0.44%;不同年份土源性线虫病感染率比较,差异有统计学意义(χ^(2)=9.002,P<0.05);2021—2023年邹城市不同性别、不同年龄段、不同职业、不同文化程度人群土源性线虫病感染率比较,差异无统计学意义(P>0.05)。结论:邹城市已达到土源性线虫病传播控制与阻断标准,应加大健康教育宣传,提高人群对土源性线虫病的认识程度,开展重点人群驱虫防治工作,降低人群感染率,加强无害化厕所管理。完善人民健康促进政策,把保障人民健康放在优先发展的战略位置,从而进一步巩固阻断土源性线虫病防治成果。

抗松材线虫病马尾松种质资源遗传多样性分析及核心种质构建

【目的】对来自安徽省林业科学研究院和异地保存在浙江省临海市林业技术推广和场圃旅游服务总站的114份抗松材线虫Bursaphelenchus xylophilus病马尾松Pinus massoniana种质进行遗传多样性与群体结构分析,构建抗性马尾松核心种质库。【方法】对114份抗性马尾松种质进行检测,使用分子生物学软件计算遗传多样性参数,并进行主坐标(PCoA)和群体结构分析。利用M策略和随机取样策略分别构建核心种质,分析不同核心种质的的遗传多样性参数,确定最适合的构建方法。【结果】114份抗性马尾松种质共检测到115个等位基因,平均有效等位基因数(N_(e))为5.54,平均Shannon’s多样性指数(I)为1.51,平均多态信息含量(P_(IC))为0.90,结果表明其具有较高的遗传多样性水平。群体结构分析将114份抗性马尾松种质分为4个亚群,主坐标分析结果与上述基本一致。根据遗传多样性参数和抽样数量综合考虑,M策略构建的核心种质能以最小的种质数保留原有种质最大的遗传多样性,为最佳的取样策略。利用该策略得到了72份核心种质,其保留了原有种质100%的等位基因数,N_(e)、I、期望杂合度(H_(e))、PIC等遗传参数的保留率分别为95.67%、94.96%、98.12%和100.00%,将构建的核心种质与原有种质进行t检验、PCoA分析和UPGMA聚类分析,结果表明两者间的遗传多样性无显著差异。【结论】114份抗性马尾松种质遗传多样性水平较高,构建的72份抗性马尾松核心种质,去除了遗传冗余,有利于抗性马尾松种质资源的有效保护和科学利用,可为优异基因发掘和新品种选育提供参考。

基于ResNet模型的松材线虫病变色疫木识别方法研究

本文使用配备高分辨率RGB数码相机的无人机,在松林上空捕捉具有高空间分辨率的航空影像,并对获取的可见光正射影像进行高程和地形特征的预处理,提取纹理信息后采用ResNet神经网络进行分类和识别训练。最终,采用深度卷积网络训练的模型对松材线虫病变色疫木进行智能识别。结果显示,平均准确率为92.29%,识别精确率最高可达96.51%,同步验证了基于ResNet模型的松材线虫病变色疫木识别方法研究的可行性,以期为松材线虫病防治提供参考。

奶山羊常见体内寄生虫病及防治

羊是草食动物,以放牧为主要饲养方式,易感染寄生虫并致病。奶山羊妊娠和泌乳期长,而驱虫药一般禁用于妊娠前期和泌乳期。定期或计划驱虫时,要避开妊娠和泌乳期,导致奶山羊寄生虫病更严重。常见的奶山羊体内寄生虫病有消化道线虫病、肺线虫病、脑脊髓丝虫病、绦虫病等。本文重点介绍奶山羊常见的几种体内寄生虫病及预防、治疗措施。

The synergistic advantage of combining chloropicrin or dazomet with fosthiazate nematicide to control root-knot nematode in cucumber production

The highly-damaging root-knot nematode(Meloidogyne spp.,RKN)cannot be reliably controlled using only a nematicide such as fosthiazate because of increasing pest resistance.In laboratory and greenhouse trials,we showed that chloropicrin(CP)or dazomet(DZ)synergized the efficacy of fosthiazate against RKN.The combination significantly extended the degradation half-life of fosthiazate by an average of about 1.25 times.CP or DZ with fosthiazate reduced the time for fosthiazate to penetrate the RKN cuticle compared to fosthiazate alone.CP or DZ combined with low or medium rate of fosthiazate increased the total cucumber yield,compared to the use of each product alone.A low-dose fosthiazate with DZ improved total yield more than a low dose fosthiazate with CP.Extending the half-life of fosthiazate and reducing the time for fosthiazate or fumigant to penetrate the RKN cuticle were the two features that gave the fumigant-fosthiazate combination its synergistic advantage over these products used singularly.This synergy provides the opportunity for farmers to use a low dose of fosthiazate which lowers the risk of RKN resistance.Farmers could combine DZ at 30 g m^-2 with fosthiazate at a low rate of 0.375 g m^-2 to control RKN and adequately control two major soil-borne diseases in cucumber greenhouses.

Effects of Two Composted Plant Pesticide Residues,Incorporated with Trichoderma viride,on Root-Knot Nematode in Balloonflower

Plant pesticide residues, such as chinaberry （Melia toosendan） residue and sand cypress （Sabina vulgaris） residue, are pesticidal plant materials discarded after the bioactive ingredient has been extracted with organic solvents. The only option for botanical pesticide residue utilization has been as landfill. Chinaberry residue （CBR） and sand cypress residue （SCR） were collected and composted in Yangling, Shaanxi Province, China. We studied the effects of chinaberry residue compost （CBRC）, CBRC incorporated with Trichoderma viride （CBRCT）, sand cypress residue compost （SCRC）, and SCRC incorporated with T. viride （SCRCv） on the root-knot nematode, Meloidogyne incognita, infesting the balloonflower （Platycodon grandiflorum）. Bioassay results indicated that stock solutions of the CBRCT and SCRCT extracts significantly inhibited egg hatching and caused high larval mortality, followed in degree by the CBRC and SCRC extracts. The CBR and SCR extracts caused very low inhibition of eggs and larvae. Supplementing potting mixtures with these four composts reduced the severity of root galling and increased the proportion of marketable roots. The severity of root galling decreased and the average weight of the marketable roots increased with an increase in all the composts when supplemented at rates from 5 to 30%. CBR- and SCR-supplemented pot soils also inhibited the nematodes, but CBR and SCR applied to the soil had a phytotoxic effect and inhibited balloonflower growth. Supplementing field soil with the composts reduced the severity of root galling and the populations of southern root-knot nematodes in the soil. CBRCT and SCRCT clearly enhanced the average weight of the marketable roots by 30.45 and 26.64%, respectively. Continuous supplementation with CBRCT or SCRCT in the same field significantly enhanced the control of the root-knot nematode, and the populations of nematodes continued to decrease with second inoculations. The populations of total Trichoderma spp. were distinctly enhanced and were maintained at high levels for a long time in the supplemented soils.

Control of Southern Root-knot Nematodes on Tomato and Regulation of Soil Bacterial Community by Biofumigation with Zanthoxylum bungeanum Seed

Biofumigation is an environmentally friendly strategy used to control nematodes and plant diseases.The volatile oil of Zanthoxylum bungeanum has high insecticidal and antibacterial activity.However,it is not known if the seed of Z.bungeanum is a suitable material for biofumigation to control southern root-knot nematodes(SRKN)on tomato,and how it may regulate the soil bacterial community structure.We used pot experiments in the greenhouse to determine the effects of Z.bungeanum seeds on SRKN,plant growth parameters,soil physicochemical and microbial characteristics.A total of 26 volatile components,including nematicidally active substances,were identified from Z.bungeanum seeds.Z.bungeanum seed biofumigation significantly reduced the SRKN population by 88.89%and 81.55%on the 50th and 100th day after transplanting,respectively.Compared to the control,the total soluble sugar,soluble solids,soluble protein,titratable acid,root activity and the fruit yield per tomato plant increased significantly.The content of soil alkali-hydrolyzed nitrogen,available potassium and the soil enzyme activities were also significantly increased.The soil bacterial diversity and the co-occurrence network complexity were increased by Z.bungeanum seed biofumigation.Relativelymore keystone OTUs in biofumigation soil had potential plant growth-promoting capabilities.The function of Z.bungeanum seed increasing tomato production in SRKN-infected soil depends on directly killing SRKN and improving soil properties.These results indicate that Z.bungeanum seed can be used as both a nematicide and a high quality organic fertilizer in tomato production.

Preparation and efficacy evaluation of Paenibacillus polymyxa KM2501-1 microbial organic fertilizer against root-knot nematodes

Root-knot nematodes(RKNs) cause huge yield losses to agricultural crops worldwide. Meanwhile, livestock manure is often improperly managed by farmers, which leads to serious environmental pollution. To resolve these two problems, this study developed a procedure for the conversion of chicken manure to organic fertilizer by larvae of Hermetia illucens L. and Bacillus subtilis BSF-CL. Chicken manure organic fertilizer was then mixed thoroughly with Paenibacillus polymyxa KM2501-1 to a final concentration of 1.5×10^(8)CFU g^(-1). The efficacy of KM2501-1 microbial organic fertilizer in controlling root-knot nematodes was evaluated in pot and field experiments. In pot experiments, applying KM2501-1 microbial organic fertilizer either as a base fertilizer or as a fumigant at the dose of 40 g/pot suppressed root-knot disease by 61.76 and 69.05% compared to the corresponding control treatments, respectively. When applied as a fumigant at the dose of 1 kg m;in field experiments, KM2501-1 microbial organic fertilizer enhanced the growth of tomato plants, suppressed root-knot disease by 49.97%, and reduced second stage juveniles of RKN in soil by 88.68%. KM2501-1 microbial organic fertilizer controlled RKNs better than commercial bio-organic fertilizer in both pot and field experiments. These results demonstrate that this co-conversion process efficiently transforms chicken manure into high value-added larvae biomass and KM2501-1 microbial organic fertilizer with potential application as a novel nematode control agent.

Toxicity Test of Different Pesticides on Tobacco Root-knot Nematodes

[Objectives]This study was conducted to quickly screen out effective and safe agents for controlling tobacco root knot nematode disease.[Methods]Six pesticides were tested and screened indoors at five different concentrations.[Results]The six pesticides all had toxic effects on the second-instar larvae of tobacco root-knot nematode,and the corrected mortality was positively correlated with the concentration and time of the pesticides,with the correlation coefficients above 0.8.From the perspective of inhibitory activity,the order was fosthiazate>abamectin>emamectin benzoate>cadusafos>ethoprophos>carbosulfan.Four pesticides that can be used in the field were selected.[Conclusions]This study provides a theoretical basis for field pesticide selection.

Morphology and Molecular Identification of Root-knot Nematode in Partial Tobacco-growing Areas in Yunnan Province

[Objectives]The species and distribution of root-knot nematodes in tobacco growing regions of Yunnan were investigated,in order to provide reference for comprehensive prevention of root-knot nematodes disease and tobacco variety layout. [Methods]Fifty-four samples of root-knot nematode host on tobacco crops were collected from Kunming,Qujing and Yuxi cities in Yunnan from August to October in 2015. The species of root-knot nematodes were identified by observing perineal patterns and molecular biological testing（ PCR of ribosomal DNA of ITS region and sequence characterized amplified region,SCAR）. [Results] There were 24 samples belonging to Meloidogyne arenaria,accounting for 44. 44%; seven M. incognita samples,accounting for 12. 96%; one M. javanica sample,accounting for 1. 85%. Eleven samples were compound populations of M. javanica and M. arenaria,accounting for 20. 37%. Five were compound populations of M. incognita and M. arenaria,accounting for 9. 26%. Three were compound populations of M. incognita and M. javanica,accounting for 5. 56%. Three belonged to compound population of M. incognita,M. javanica and M. arenaria,accounting for 5. 56%. [Conclusions] The species of root-knot nematodes in tobacco growing areas of Yunnan mainly include M. incognita,M. javanica and M. arenaria. M. arenaria is the dominant population.

Occurrence of Root-Knot and Reniform Nematodes in Ornamental Plants Grown in Aligarh Muslim University Campus, India

An extensive survey of about 50 ornamental plants growing in A.M.U. campus were carried out to find out the infection of root-knot (Meloidogyne spp.) and reniform nematodes (Rotylenchulus reniformis). Out of 50 species of ornamental plants studied, 29 species of these plants were found to be infected with root-knot nematodes (Meloidogyne spp.) and 15 species were infected with reniform nematode (Rotylenchulus reniformis). The highest percentage of infection of root-knot nematodes was observed in Impatiens balsamina (100%) and reniform nematode was observed in Hibiscus rosa-sinensis (56%). Among the Meloidogyne spp. the highest percentage of infection of M. incognita was observed in Pseuderanthemum atropurpureum (80%) whereas, the highest percentage of infection of M. javanica and M. arenaria was observed in Mirabilis jalapa (72%) and Celosis cristata (28%).

Biological Control of Root-Knot Nematode Meloidogyne incognita in Psoralea corylifolia Plant by Enhancing the Biocontrol Efficacy of Trichoderma harzianum Using Press Mud

Meloidogyne incognita is a plant pathogen causing root-knot disease and loss of crop yield.The present study aimed to use Trichoderma harzianum as a biocontrol agent against plant-parasitic nematodes and used press mud,which is a solid waste by-product of sugarcane,as a biocontrol agent and biofertilizer.Therefore,the combined application of T.harzianum and press mud may enhance nematode control and plant growth.Elemental analysis of press mud using scanning electron microscopy(SEM)integrated with an Energy Dispersive X-ray(EDX)analyzer revealed the presence of different elements such as C,O,Mg,Si,P,K,Ca,Cu and Zn.In addition,a greenhouse study was conducted to investigate the combined effects of press mud and T.harzianum on M.incognita reproduction and growth and the biochemical features of Psoralea corylifolia.The results showed that plant length,dry biomass,leaf area,the number of seeds per plant,chlorophyll a,chl b,carotenoid content,nitrate reductase,carbonic anhydrase,and nitrogen content were significantly increased(P≤0.05)in the T2 plants(plants were treated with 100 g of press mud+50 mL T.harzianum before one week of M.incognita inoculation),over inoculated plants(IC).Antioxidant enzyme activity of ascorbate peroxidase(APX),catalase(CAT),peroxidase(POD),and superoxide dismutase(SOD)in the foliage of P.corylifolia was significantly increased when plants were treated with press mud+T.harzianum.A significant reduction in the number of egg masses,nematode population,and root-knot index(RKI)was found in plants with T2 plants.These results suggest that the combined application of T.harzianum and press mud has the potential to control the M.incognita infection and can be used as an environmentally safe alternative to chemical nematicides and also help in the removal of sugarcane waste that causes environmental pollution.

Preliminary Study on Mixed Use of Agaricus bisporus Residue and Microbial Agent to Control Cucumber Root-knot Nematode

Single or mixed use ofAgaricus bisporus residue and microbial agent had better control effect on cucumber root-knot nematode disease in greenhouse. The results showed that the control effect of single use of A. b/sporus residue was 32.9% - 34.7%, and the yield increasing rate was 2.1% - 8.7% ; the control effect of mixed use ofA. b/sporus residue and microbial agent was 59. 1% - 63. 6%, and yield increasing rate was 2.6% - 3.5%. The experimental dose had no ad- verse effects on soil physical and chemical properties. The mixed use of A. b/sporus residue and microbial agent was one of the effective ways to control root-knot nematode disease.

Bacterial artificial chromosome library construction of root-knot nematode resistant pepper genotype HDA149 and identification of clones linked to Me3 resistant locus

Pepper （Capsicum annuum. L.） is a widely cultivated vegetable crop worldwide and has the second largest planting area and the first largest vegetable output and value in China. Pepper root-knot nematode （Meloidogyne spp.） is one of the most serious pests of pepper, which caused huge losses every year. Previous studies showed that the Me3 gene is resistant to a wide range of Meloidogyne species, including M. arenaria, M. javanica, and M. incognita. HDA149, a double haploid pepper genotype, harboring the root-knot nematode resistance gene Me3, was used to construct bacterial artificial chro- mosome library （BAC） via the vector of CopyControFM pCC1 in this study. The library consists of 210 200 BAC clones and is equivalent to 5.3 pepper genomes. The average insert size is 95 kb, and most of them are 90-120 kb; but the empty clones are less than 3%. In order to screen the BAC library easily, 550 super pools with 384 BAC clones of each pool were further developed in this study. Specific primers from Me3 gene locus were used for BAC library screening, and more than 20 positive BAC clones were obtained. Then the selected positive BAC clones were analyzed by restriction enzyme digestion, BAC-end sequencing, marker development, and new positive BAC clones exploration, respectively. Finally, the contig with total length of about 300 kb linked to the Me3 locus was constructed based on chromosome walking strategy, which made a solid foundation for the cloning of the important root-knot nematode resistance gene Me3.

Genetic Mapping of Root-knot Nematode Resistance Genes in Solanaceous Vegetables

Root-knot nematodes are becoming more and more harmful to solanaceous vegetables. The most economical and effective way to deal with root-knot nematode disease is to breed varieties with disease resistance. This paper reviewed the recent research progress and achievements of tomato, pepper, eggplant and potato on root-knot nematode disease resistance gene characteristics, disease resistance gene mapping and disease resistance gene molecular markers, and prospects for future research directions.

安徽省松材线虫病生态环境影响评价

为探讨松材线虫病生态环境影响评价,本文在掌握安徽省松材线虫病分布情况的基础上,以2021年为研究基准年,设置多项指标,就松材线虫病对生态环境的影响进行定性分析和定量评估。结果表明,2021年松材线虫病对安徽省生态环境影响价值损失为25.69亿元。比照2021年安徽省GDP和林业行业社会总产值,松材线虫病对安徽省生态环境影响的价值分别占前两者的0.060%和0.505%,可见其对安徽省生态环境以及可持续发展均有一定影响。

泾县松材线虫病防治现状及防控对策

本文介绍了安徽省泾县松材线虫病的防治现状及采取的防治措施,分析了防治过程中存在的问题,并从强化风险排查与治理同步开展,落实松材线虫病防治各方责任、建立联动监管机制,强化科技创新、解决关键技术难题等方面提出了防控建议。

金寨县松材线虫病防控存在的问题及防控对策

松材线虫病被称为松树“癌症”,是造成松林毁灭性的一种灾害,防控工作至关重要。通过对六安市金寨县松材线虫病防控工作现状的分析,总结该县防控工作中经验做法和存在的主要问题,并针对性地提出防控对策,以期为该县防控工作提供参考。

江苏省肠道线虫病防治效果分析

目的评估化疗对防治肠道线虫病的效果，并为制定下阶段防治对策提供依据。方法在全国首次人体寄生虫分布调查中签县（市）分层抽样，采用相同的方法调查人群感染率；收集驱虫服药、社会经济等资料进行分析。结果人群肠道线虫总感染率、蛔虫、钩虫、鞭虫和蛲虫感染率分别由防治前的59．32％、39．51％、21.80％、27．30％和36．08％下降为3．01％、0．83％、1．07％、1．31％和2．78％。苏南、苏中和苏北3个区域感染率分别下降了96．96％、97．65％和91．43％。全省1994～2005年共驱虫服药8390万人次，人均服药1．40次。苏南、苏中和苏北人均服药0．97、2．03、和1．26次。苏中地区服药率最高，感染率下降幅度最大。结论服药驱虫对降低人群肠道线虫感染率有十分显著的效果，今后要加强对重点地区和高危人群的防治，对不同感染率地区采取分类指导的防治措施。