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1.
Pleurotus ostreatus对线虫作用机理的研究   总被引:10,自引:1,他引:9  
 本文详细地研究了粗皮侧耳(Pleurotus ostreatus)对线虫(Panagrellus redivivus)的致病过程、线虫感病症状及菌丝与线虫的相互作用。探明了粗皮侧耳对线虫致病的实质是杀主寄生,菌丝分泌的毒素首先将线虫击倒并杀死,然后菌丝从线虫体孔侵入,或靠酶和机械力的作用从表皮侵入,最后消解、吸收和利用线虫。一般菌丝与线虫接触1~5min线虫被击倒,20~30min卵和幼虫解体,4~6h成虫死亡,12h后菌丝侵入虫体营腐生生活。菌丝也可不侵染线虫,仅靠毒素将线虫杀死,在酶的协同作用下将线虫分解,直接吸收利用线虫。若菌丝分泌的毒素不足以杀死线虫,纵然菌丝与线虫充分接触也不能侵染活线虫。试验还表明,该菌平板培养产生的毒素,除去菌丝也能杀死线虫。  相似文献   

2.
 拟禾本科根结线虫(Meloidogyne graminicola)为水稻的重要土传病原,可严重为害水稻。本研究旨在探究水稻中丝裂原活化蛋白激酶5(MPK5)稳态失衡对拟禾本科根结线虫与水稻亲和互作的影响,并初步探讨其机制。首先,通过线虫侵染试验发现,在水稻中超表达和沉默MPK5 引发的MPK5 稳态失衡均可抑制拟禾本科根结线虫与水稻的亲和互作。qRT-PCR 分析结果显示,与水稻野生型不同,在MPK5 超表达和沉默水稻株系中MPK5 均受拟禾本科根结线虫诱导表达。同时,拟禾本科根结线虫可抑制MPK5 超表达株系中几丁质酶的表达,但诱导MPK5 沉默株系中病程相关基因PR5PR10 的表达。上述试验结果表明,MPK5 稳态失衡可导致MPK5 响应拟禾本科根结线虫的侵染,且在MPK5 超表达和沉默水稻株系中MPK5 介导水稻产生拟禾本科根结线虫抗性的机制不同。  相似文献   

3.
 松材线虫病是世界性的检疫病害,严重威胁松林等森林资源和生态安全。有研究表明,Feminization(fem)基因家族在秀丽隐杆线虫中参与性别决定和分化。本研究克隆了松材线虫fem-1基因,并对其表达特征和调控功能进行研究。结果表明,该基因cDNA全长为856 bp,包含681 bp的开放阅读框,编码226个氨基酸,进化分析显示与秀丽隐杆线虫位于同一进化分支。荧光定量PCR以及原位杂交结果显示, fem-1基因在松材线虫各个发育阶段均有表达,其中在2龄虫期表达水平最高;在卵期至3龄虫期阶段于虫体中后部表达,而发育后期,多位于皮下细胞中表达,肠道、性腺等部位极少出现杂交反应。利用RNA干扰技术沉默fem-1基因后,线虫种群雌雄比例出现下降,说明fem-1基因可能参与松材线虫性别分化和决定过程。研究结果有助于了解松材线虫性别决定相关基因表达特性与功能,为深入研究松材线虫发育生物学提供一定的理论依据。  相似文献   

4.
为了从中草药中寻找高效杀线虫活性物质,本文测定了36种中草药提取物对松材线虫及其卵的毒杀活性。结果表明,牡丹皮、黄连和大黄3种中药的乙醇提取物杀线虫活性较强,以提取物浓度为10 g/L处理松材线虫72 h后,校正死亡率均为100%。3种中药提取物处理松材线虫72 h后半致死浓度(LC50)分别为1.81、0.2638和1.07 g/L。杀卵活性结果表明,3种中药提取物处理72 h后,线虫卵的孵化率均低于20%,虫卵的校正死亡率均高于60%。利用乙酸乙酯和水作溶剂对3种中草药进行初步的杀线活性成分分离的结果表明,牡丹皮的杀线活性物质存在于乙酸乙酯萃取物中,黄连和大黄的杀线活性物质存在于水萃取物中。3种中药的不同萃取物处理松材线虫72 h后的LC50分别为0.712、2.370和0.067 g/L。  相似文献   

5.
粗皮侧耳对线虫致病力的研究初报   总被引:2,自引:0,他引:2  
 Thorn和Barron (1984,1987)报道Pleurotus能杀死线虫,并就粗皮侧耳(P.ostreatus)的培养特性和杀虫机理作了初步的研究。1989年在进行食线虫真菌分离时,用Thorn法从土壤中分离获一种不产孢具锁状联合的菌丝,经培养产生子实体后鉴定为侧耳属粗皮侧耳(Pleurotus ostreatus)。  相似文献   

6.
根结线虫是一类严重为害作物的寄生线虫,分布于世界各地,且寄主范围广。前期试验表明,日本曲霉Aspergillus japonicus ZW1发酵滤液对南方根结线虫Meloidogyne incognita 2龄幼虫(J2)具有毒杀作用,发酵过程中产生表面光滑球形菌丝体和表面辐射状球形菌丝体,且两种菌丝体发酵滤液的杀线虫效果具有显著差异。表面光滑球形菌丝体的发酵滤液处理南方根结线虫J2的校正死亡率在24 h达100%,显著高于表面辐射状球形菌丝体发酵滤液处理的死亡率(12.7%)。本研究通过对菌株ZW1发酵的温度、转速、培养基、光照和黑暗等条件优化表明,菌株ZW1的最优培养温度25℃和转速150 r/min,以Czapek培养基为基础培养基的最优碳源为蔗糖30 g/L和氮源KNO33 g/L,光照和黑暗条件下培养不影响菌株ZW1杀线虫活性;评价煮沸和4℃保存发酵滤液的杀虫效果结果表明,发酵液杀线虫活性随着贮藏时间发生变化,发酵液煮沸对菌株ZW1发酵液的杀线虫活性无影响,4℃保存1年的发酵滤液处理J2的校正死亡率仍保持87.8%。菌株ZW1代谢产物对南方根结线虫J2具有良好的毒杀作用,值得进一步研究和开发利用。  相似文献   

7.
 西洋参(Panax quinquefolium L.)原产北美洲,1978年引入我国并试种成功。西洋参作为一种名贵中药材,是我国中医药及医药保健品的重要成分之一,同时也是中草药栽培的主要品种之一。随着种植面积和种植区域的扩大,西洋参根部病害在生产上具有逐年加重的趋势,严重制约了西洋参产业的发展。在真菌和细菌病原物引致根病中,根际的植物寄生线虫往往是复合侵染的重要因子之一。  相似文献   

8.
 采用PCR技术对河南郑州禾谷孢囊线虫群体的核糖体基因(ribosomal DNA,rDNA)内转录间隔区(Internal Transcribed Spacers,ITS)进行扩增,获得片段长度约为1040bp。利用UPGMA方法分析了河南郑州禾谷孢囊线虫群体与近缘种的系统发育关系,结果表明:中国Heterodera avenae群体,H.australisH.pratensis亲缘关系很近。8种限制性内切酶(Restriction Enzyme,RE)酶切禾谷孢囊线虫ITS的扩增产物,其中HindⅢ、AvaⅠ不能酶切PCR产物;Alu Ⅰ酶切PCR产物,获得560bp和480bp2个片段;RsaⅠ和Hinf Ⅱ酶切后分别得到3个片段(700、320、20bp和820、180、40bp);CfoⅠ是3个酶切位点(740、150、110、40bp);HaeⅢ和MvaⅠ能分别清晰地观察到3个片段(420、350、180bp和400、340、280bp),但有微小片段无法清晰观察到。9个种群所得RFLP图谱一致,说明郑州禾谷孢囊线虫群体可能是同一种群且不同于欧洲群体(typeA)和印度群体(typeB)的C型。  相似文献   

9.
 茶苗根结线虫病主要发生于一、二年生实生苗上,重病地发病率可达100%,死苗率在50%以上。据在浙江省的不完全调查,已知有18个县(市)发现此病。病原线虫经初步鉴定,主要为南方根结线虫(Meloidogyne incognita)与花生根结线虫(M.arenaria),而爪哇根结线虫(M.javanica)与泰晤士根结线虫(M.thamesi)均少见。试验表明,杭州茶区病原线虫一年发生不完整8代,大约20~30天完成一代,世代重叠明显。  相似文献   

10.
浙江小麦根围土壤腐霉(Pythium spp.)的一些生态学研究   总被引:6,自引:0,他引:6  
 本文对小麦根围土壤中的腐霉Pythium种类、种群数量消长及其致病性作了初步研究。作者从不同生育期的小麦根围和内根围共分离出203个腐霉菌株,除69个菌株缺乏产生有性器官而未能鉴定外,其余134个菌株分别属10个腐霉种,其中粘腐霉P.adhaerens、链状腐霉P.catenulatum和绚丽腐霉P.pulchrum为浙江省分布新记录。P.spinosum是优势腐霉种类,在小麦根围和内根围出现率分别为27.43%和35.71%,P.ultimumP.irregulare也较为常见,而P.aphanidermatum却极少出现。在小麦苗期和分蘖期腐霉数量较丰富,生育中后期较贫乏,这一消长变化可能主要与小麦生育期和土壤温度有关。致病性试验结果表明:P.irregulareP.spinosum分别对小麦和水稻有较强的致病作用;P.aphanider-matumP.irregulareP.spinosum则对茄子、辣椒和番茄的致病力较强。P.spinosumP.ultimumP.irregulare的种内菌株间致病性差异不明显。  相似文献   

11.
2012年5月-7月在甘肃省白银市采集了番茄、黄瓜、豇豆等几种保护地蔬菜的25个根结线虫群体.直接解剖获得雌虫,通过雌虫会阴花纹观察,结合酯酶和苹果酸脱氢酶(MDH-EST)测定,鉴定出所收集的25个群体中有16个为南方根结线虫[Meloidogyne incognita (Kofoid&White)],9个为爪哇根结线虫[M.javanica (Treub)].南方根结线虫为优势种群,本次试验也是首次在甘肃省发现爪哇根结线虫.  相似文献   

12.
Nine Myrobalan plum clones ( Prunus cerasifera ) obtained from in vitro propagation were tested for host suitability to four root-knot nematode (RKN) isolates ( Meloidogyne incognita (2), M. javanica (1), and M. hispanica (1)) and one root-lesion nematode (RLN), Pratylenchus vulnus , isolate. The clones are characterized according to the Ma major resistance genes that control resistance to M. arenaria , M. incognita and M. javanica and are categorized into five resistant (R) and four host (H) clones to these RKN species. As expected, the clones ranged, regardless of the RKN species or isolate, into the same distinct R (P.2175, P.1079, P.2980, H.17 and H.21) and H (P.2794, H.18, H.23 and P.16.5) groups for RKN resistance. The P. vulnus tests showed that all the clones had higher final populations than initial populations ( P f :  P i > 1) and that P f :  P i ratios were equivalent in each RKN resistance group (R or H). Consequently, resistant alleles of RKN Ma genes in Myrobalan plum have no major effect on RLN multiplication. Our data must be taken into account for breeding strategies aimed at incorporating multiple resistance to both RKN and RLN in Prunus spp.  相似文献   

13.
4种常见根结线虫基因组DNA的RAPD分析   总被引:9,自引:2,他引:7  
 用120个随机引物对4种常见根结线虫10个小种和类型进行了全基因组随机扩增DNA多态性(RAPD)分析,筛选出的11个适宜引物共扩增出91条RAPD谱带,86条是多态性谱带,占总谱带的94.5%;OPL12、OPK01对4种根结线虫种及其小种扩增的谱型有明显的特异性。聚类分析显示在种间水平上4种根结线虫中花生根结线虫和爪哇根结线虫亲缘关系最近,遗传距离为0.532,北方根结线虫与另外3种根结线虫的亲缘关系最远,平均遗传距离为0.786;种下水平上同种根结线虫的不同小种和类型间存在不同程度的遗传差异,南方根结线虫4个生理小种间,花生根结线虫2个生理小种间亲缘关系较近,爪哇根结线虫2个酯酶谱带类型间,北方根结线虫2个细胞生物学小种间遗传差异较大。在RAPD技术的基础上探索根结线虫分类鉴定的分子方法有着良好的前景。  相似文献   

14.
海南岛葫芦科蔬菜根结线虫危害性调查与种类鉴定初报   总被引:1,自引:0,他引:1  
对海南11个市县的葫芦科蔬菜进行根结线虫危害性调查,结果显示,大部分地区发病率在50%以上;其中琼中腰子、澄迈长安和琼中营根主产菜区的病情指数分别达到了47.12、47.14和40,已造成严重损失。采自海南11个县市5种葫芦科蔬菜24个根结线虫种群经单卵块纯化培养,运用形态学和同工酶的方法对其进行种类鉴定,结果表明,南方根结线虫占总数的79.17%,爪哇根结线虫占总数的12.5%,根结线虫疑似新种或新纪录种占总数的8.3%。南方根结线虫是危害海南葫芦科蔬菜的优势种。  相似文献   

15.
ABSTRACT The fungal biocontrol agent, Trichoderma harzianum, was evaluated for its potential to control the root-knot nematode Meloidogyne javanica. In greenhouse experiments, root galling was reduced and top fresh weight increased in nematode-infected tomatoes following soil pretreatment with Trichoderma peat-bran preparations. The use of a proteinase Prb1-transformed line (P-2) that contains multiple copies of this gene improved biocontrol activity in the greenhouse experiments compared with the nontransformed wild-type strain (WT). All the Trichoderma strains showed the ability to colonize M. javanica-separated eggs and second-stage juveniles (J2) in sterile in vitro assays, whereas P-2 also penetrated the egg masses. This protease-transformed line presented the same nematicidal and overall proteolytic activity as the WT in in vitro tests in which concentrated soil extracts from Trichoderma-treated soils immobilized the infective J2. However, the J2 immobilization and proteolytic activities of both P-2 and the WT were higher than those obtained with strain T-203. Characterization of the activity of all Trichoderma strains soil extracts on J2 showed that it was heat resistant and restricted to the low-molecular-weight fraction (less than 3 kDa). It is suggested that improved proteolytic activity of the antagonist may be important for the biological control of the nematodes.  相似文献   

16.
Five different dry and five green plant leaves were tested against Meloidogyne javanica and Rotylenchulus reniformis, as bio-agents in controlling these nematodes infecting sunflower. Data generally, indicated that all the tested manures significantly (P≤0.05) reduced the total number of nematodes in root and soil. The best materials were datura dry leaves on M. javanica and lime dry leaves on R. reniformis which gave very good results against nematodes (86.4 and 95.1% female reduction, respectively). Plant growth was significantly (P≤0.05) better, in most cases, in shoots, roots and flowering discs weight.  相似文献   

17.
Five different dry and five green plant leaves were tested against Meloidogyne javanica and Rotylenchulus reniformis, as bio-agents in controlling these nematodes infecting sunflower. Data generally, indicated that all the tested manures significantly (P≤0.05) reduced the total number of nematodes in root and soil. The best materials were datura dry leaves on M. javanica and lime dry leaves on R. reniformis which gave very good results against nematodes (86.4 and 95.1% female reduction, respectively). Plant growth was significantly (P≤0.05) better, in most cases, in shoots, roots and flowering discs weight.  相似文献   

18.
用PhastSystem电泳仪快速鉴定根结线虫种类   总被引:7,自引:0,他引:7  
 应用瑞典Pharmacia Biotech.公司开发的全自动快速水平电泳仪(PhastSystem)进行酯酶和苹果酸脱氢酶电泳,对云南省烟草和观赏植物一串红上的根结线虫进行快速鉴定,得出4种根结线虫:花生根结线虫(Meloidogyne arenaria)、爪哇根结线虫(M.javanica)、南方根结线虫(M.incognita)和北方根结线虫(M.hapla)。文章提供电泳方法,认为PhastSystem电泳仪是根结线虫种类快速鉴定的理想设备。  相似文献   

19.
近年来,随着我国荞麦面积的迅速增加,根结线虫病呈逐年加重趋势,严重影响了荞麦的产量与品质。本研究于2014年对西南10个地区17个乡镇秋播苦荞麦根结线虫的分布、发生种类以及危害程度进行了调查。结果表明,西南地区危害荞麦的根结线虫种类有南方根结线虫(Meloidogyne incognita)、爪哇根结线虫(M.javanica)和花生根结线虫(M.arenaria)3种,其中南方根结线虫为优势种群。田间根结线虫种群大多数为单一种群,23.5%的样品为南方根结线虫与爪哇根结线虫(或花生根结线虫)组成的混合种群。调查发现前作为烟草或马铃薯的地块,荞麦根结线虫发生危害严重,平均被害株率为6.0%~77.5%,病情指数为1.4~26.1,而前作为玉米的荞麦根结线虫则较轻,被害株率最高为16.0%,相应病情指数为2.3。  相似文献   

20.
The effects were investigated, under controlled conditions, of single and joint inoculation of olive planting stocks cvs Arbequina and Picual with the arbuscular mycorrhizal fungi (AMF) Glomus intraradices , Glomus mosseae or Glomus viscosum , and the root-knot nematodes Meloidogyne incognita and Meloidogyne javanica , on plant performance and nematode infection. Establishment of the fungal symbiosis significantly increased growth of olive plants by 88·9% within a range of 11·9–214·0%, irrespective of olive cultivar, plant age and infection by M. incognita or M. javanica . In plants free from AMF, infection by Meloidogyne spp. significantly reduced the plant main stem diameter by 22·8–38·6%, irrespective of cultivar and plant age. Establishment of AMF in olive plants significantly reduced severity of root galling by 6·3–36·8% as well as reproduction of both Meloidogyne spp. by 11·8–35·7%, indicating a protective effect against parasitism by root-knot nematodes. Infection by the nematodes influenced root colonization by AMF, but the net effect depended on the AMF isolate–olive cultivar combination. It is concluded that prior inoculation of olive plants with AMF may contribute to improving the health status and vigour of cvs Arbequina and Picual planting stocks during nursery propagation.  相似文献   

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