小麦禾谷胞囊线虫不同抗性品种中几丁质酶基因Cht4的表达分析

以小麦稳定表达的肌动蛋白(Actin)为对照,利用半定量RT-PCR技术对小麦禾谷胞囊线虫(Heterodera ave nae)接种后在不同抗性品种不同时期不同部位的几丁质酶基因Cht4的表达量进行了分析.结果表明,接种12 h后,Cht4的表达量无明显的增加,抗、感品种之间差异不明显;接种36 h后,抗、感品种中的Cht4的表达量都明显增加,抗性品种中的表达量明显高于感病品种,叶部表达量高于根部的表达量;接种60 h后,抗、感品种中Cht4的表达量都维持在较高的表达水平,抗病品种比感病品种中Cht4的表达量高;接种84 h后,感病品种与接种前相比变化不明显,而抗病品种的表达量仍高于接种前的表达量.     

Molecular diagnosis and direct quantification of cereal cyst nematode (Heterodera filipjevi) from field soil using TaqMan real-time PCR

Heterodera filipjevi continues to be a major threat to wheat production worldwide. Rapid detection and quantification of cyst nematodes are essential for more effective control against this nematode disease. In the present study, a TaqMan-minor groove binder (TaqMan-MGB) probe-based fluorescence quantitative real-time PCR (qPCR) was successfully developed and used for quantifying H. filipjevi from DNA extracts of soil. The primers and probe designed from the obtained RAPD-SCAR marker fragments of H. filipjevi showed high specificity to H. filipjevi using DNA from isolates-confirmed species of 23 Heterodera spp., 1 Globodera spp. and 3 Pratylenchus spp. The qPCR assay is highly sensitive and provides improved H. filipjevi detection sensitivity of as low as 4^–3 single second-stage juvenile (J2) DNAs, 10^–3 female DNAs, and 0.01 μg μL^–1 genomic DNAs. A standard curve relating to the threshold cycle and log values of nematode numbers was generated and validated from artificially infested soils and was used to quantify H. filipjevi in naturally infested field soils. There was a high correlation between the H. filipjevi numbers estimated from 32 naturally infested field soils by both conventional methods and the numbers quantified using the qPCR assay. qPCR potentially provides a useful platform for the efficient detection and quantification of H. filipjevi directly from field soils and to quantify this species directly from DNA extracts of field soils.     

A new pathotype characterization of Daxing and Huangyuan populations of cereal cyst nematode(Heterodera avenae) in China

The cereal cyst nematode(CCN, Heteroder aavenae) causes serious yield loss on cereal crops, especially wheat, worldwide. Daxing population in Beijing City and Huangyuan population in Qinghai Province, China, are two CCN populations. In this study, the CCN pathotypes of Daxing and Huangyuan populations were characterized by tests on 23 standard "International Test Assortment" with the local species Wenmai 19 as the susceptible control. Tested materials were grouped by three nematode populations' virulence on resistant genes(Rha1, Rha2, Rha3, Cre1) and nonresistant genes, varieties and lines. Both Daxing and Huangyuan populations were avirulent to Ortolan(Ha1). Barley cvs. Ortolan, Siri, Morocco, Bajo Aragon 1-1, and Martin 403-2 were all resistant to both populations. Cultivars Herta, Harlan 43 and wheat Iskamish-K-2-light were all susceptible to Huangyuan population, all of them, however, were resistant to Daxing population. The other five oats were all resistant to the two tested CCN populations. Except Iskamisch K-2-light, all the other wheat cultivars(Capa, Loros×Koga, AUS 10894, and Psathias) were susceptible to Daxing population. Because the pathotypes of the two tested CCN populations in Beijing and Qinghai were not identical to any of the 13 pathotypes previously characterized by the test assortment, we classified Daxing and Huangyuan populations as the new pathotypes, named Ha91.     

大豆抗孢囊线虫育种研究进展

综述了大豆抗孢囊线虫的生化机制及DNA分子标记(RFLP、RAPD)技术在大豆抗孢囊线虫病研究中的应用,大豆抗孢囊线虫各个生理小种的遗传分析,大豆抗孢囊线虫病育种的研究概况及抗病品种鉴定方法的进展,并对未来研究方向作了展望.     

小麦孢囊线虫病的特征及防治

本文综述了小麦孢囊线虫病的概况,提出了植物检疫、抗性品种选育、农业防治、化学防治、生物防治等综合防控策略.     

大豆胞囊线虫病的生防因子研究进展

综述了大豆胞囊线虫的各类生防因子,如食线虫真菌、食线虫细菌、杀线虫植物、捕食性线虫和捕食性土壤动物等,其中研究较深入的是食线虫真菌和细菌,食线虫真菌可归纳为5种类型,即捕食性真菌、专性内寄生菌物、机会真菌、产毒真菌和菌根菌;另外,还对其他生防因子的最新研究结果进行了归类综述,并对大豆胞囊线虫的生物防治进行了展望。     

大豆抗孢囊线虫3号生理小种相关基因PCR检测方法的建立与应用

根据甜菜的抗线虫病基因保守序列,设计合成了4对引物,从中筛选出1对引物,对8份经抗孢囊线虫3号生理小种常规鉴定的大豆品种(6份抗病、2份感病)进行了PCR检测.结果表明,6份抗病品种出现了1条600bp的特异片段,而2份感病品种未出现任何条带.这与常规鉴定结果相一致.PCR Sothern杂交验证了所获得特异片段与抗线虫病基因的同源性,证明使用该方法检测大豆抗孢囊线虫病基因简单、快速、方便、可行.     

大豆胞囊线虫抗性候选基因Rhg1的克隆及其功能验证

大豆胞囊线虫(Soybean cyst nematode,SCN)是大豆生产上一种危害严重的世界性害虫,给大豆的产量和品质造成极大的损失。大豆抗性品种选育是其防治措施中最经济、有效的方法。文章拟利用RT-PCR方法克隆得到大豆胞囊线虫抗性候选基因Rhg1,通过构建植物过量表达载体pCAMBIA3301/Rhg1,并采用根癌农杆菌介导的大豆子叶节方法转化大豆东农50。PCR检测草丁膦抗性植株,表明目的基因已经整合到了大豆基因组中;实时荧光定量PCR结果也进一步证实,目的基因在转基因植株中有较高水平的表达丰度。在胞囊线虫的侵蚀下,转基因植株体内的超氧化物歧化酶含量显著高于野生型植株,而丙二醛含量低于野生型植株。研究证实了Rhg1为大豆胞囊线虫的主抗基因,同时为大豆胞囊线虫的分子抗性育种提供理论基础。     

东北地区大豆孢囊线虫病发生和防控技术研究进展

大豆孢囊线虫(Heterodera glycines Ichinohe)病是大豆生产上重要经济病害之一.东北地区作为我国大豆主产区,大豆种植面积增加同时该地区病害呈逐年加重趋势.为有效防控大豆孢囊线虫病,文章阐述东北地区大豆孢囊线虫生理小种种类、分布和变异及病害发生程度等规律.根据该区大豆孢囊线虫病害发生特点综述已有防控技术研究进展,主要包括农业措施、化学防治、生物防治、利用抗病品种等.最后展望未来潜在防控技术,以期为东北地区大豆丰产和农业可持续发展提供理论依据和技术支撑.     

不同小麦品种(系)对禾谷孢囊线虫病的抗性鉴定

为了筛选抗小麦禾谷孢囊线虫的小麦材料,通过大田小区试验,对10个具有优良农艺性状的小麦品种(系)抗孢囊线虫病性能及产量进行了鉴定,结果表明:各供试品种(系)抗病程度和小麦产量存在明显差异,但未发现免疫品种。其中CD01最为抗病,平均病指为19.3;豫展1号和CD992005发病最重,平均病指分别高达41.6和40.0。且产量明显低于其他品种。株孢囊数与植株感病程度和产量高低之间的关系并不完全一致。     

Bioassay to Forecast Cereal Cyst Nematode Damage to Wheat in Fields

Several simple agronomic practices such as crop rotation, timing of sowing, no-till management, and resistant cultivars can reduce damage by the cereal cyst nematode (CCN), (Heterodera avenae), but the damage levels are unpredictable. The objective of the present study was to develop a fast assay that would forecast the potential damage to wheat by CCN in the fields. Our forecast procedure was based on the SIRONEM bioassay with several modifications in the sampling and incubation of field soil samples and cultivation in them of wheat seedlings. For CCN disease assessment, a damage model that takes account of CCN infection and its damage to roots was developed. Field experiments were established to validate the resulting damage model, and showed a correlation between the forecast damage and field rating of CCN infection. This assay has advantages over other CCN estimation methods because it directly forecasts the potential crop damage in the field and it requires a relatively short period to obtain the data. According to the forecast damage and weather conditions, the most appropriate crop management regime, especially of sowing, can be chosen for each field assayed.     

小麦孢囊线虫江苏群体的形态学与分子特征鉴定

【目的】明确小麦禾谷类作物孢囊线虫（cereal cyst nematodes,CCN）江苏群体的种类组成及群体间遗传变异情况,为抗病品种的选育、利用以及病害综合防治提供依据。【方法】对江苏省的13个代表性CCN群体进行孢囊、阴门锥和2龄幼虫的形态观察和形态测计并与相似种进行比较;PCR扩增上述群体的rDNA-ITS区并克隆测序,构建基于ITS序列的系统发育进化树。【结果】通过形态观察和形态测计值的比较,所测定的江苏群体均与已报道的禾谷孢囊线虫（Heterodera avenae）中国群体的测计值相接近;系统进化关系分析显示CCN江苏群体、国内其它地区以及国外禾谷孢囊线虫群体均处于同一大的进化分子簇,且国内和国外群体分别处于不同的进化分支。【结论】所测定的13个江苏省CCN代表性群体均为禾谷孢囊线虫,各群体间形态及ITS序列变异较小,江苏省目前尚未发现菲利普孢囊线虫（H. filipjevi）。     

Chemical mutagenesis and soybean mutants potential for identification of novel genes conferring resistance to soybean cyst nematode

The resistance of soybean (Glycine max (L.) Merr.) to soybean cyst nematode (SCN, Heterodera glycines Ichinohe), which is a devastating pathogen in soybean production and causes a large quantity of annual yield loss worldwide, can shift during the long-term interaction and domestication. It is vital to identify more new resistance genetic sources for identification of novel genes underlying resistance to SCN for management of this pathogen. In the present study, first, two ethane methylsulfonate-mutagenesis soybean M2 populations of PI 437654, which shows a broad resistance to almost all of SCN races, and Zhonghuang 13, which is a soybean cultivar in China conferring strong resistance to lodging, were developed. Many types of morphological phenotypes such as four- and five-leaflet leaves were observed from these two soybean M2 populations. Second, 13 mutants were identified and confirmed to exhibit alteration of resistance to SCN race 4 through the forward genetic screening of 400 mutants of the PI 437654 M2 population, the rate of mutants with alteration of SCN-infection phenotype is 3.25%. Third, these identified mutants were further verified not to show any changes in the genomic sequences of the three known SCN-resistant genes, GmSHMT08, GmSNAP18 and GmSANP11, compared to the wild-type soybean; and all of them were still resistant to SCN race 3 similar to the wild-type soybean. Taken together, we can conclude that the 13 mutants identified in the present study carry the mutations of the new gene(s) which contribute(s) to the resistance to SCN race 4 in PI 437654 and can be potentially used as the genetic soybean sources to further identify the novel SCN-resistant gene(s).     

孢囊线虫抗性基因导入及夏大豆高产材料创造研究

利用抗孢囊线虫的北京小黑豆和哈尔滨小黑豆为抗源种质 ,以有性杂交导入抗线虫基因并创造高产性能 ,育成了黄豆、茶豆、黑豆抗线虫系列种质和黄豆、黑豆、茶豆抗线虫品种齐黄 2 5、齐茶豆 1号、齐黑豆2号。并相继应用这些创新抗源育成了一批抗孢囊线虫、高产、优质、生育期适于山东种植的有希望的优异材料 9172 4、93746、93747、93748等 ,可望把我省大豆科研、生产推向新台阶、新水平。在早期世代识别出有选择潜力的组合 ,进行重点选育 ,重点鉴定 ,将病地田间选择和病土盆栽抗性鉴定结合交替进行 ,是获得抗病性兼丰产性的关键技术     

小麦孢囊线虫病综合防治研究进展

小麦孢囊线虫病是我国小麦生产上的重要病害,生产上亟需安全有效的防治方法。从选育和利用抗病品种、农业防治、化学防治以及生物防治4个方面对小麦孢囊线虫病的相关防治研究进展进行论述,并探讨了小麦孢囊线虫病综合治理的发展趋势,以期为小麦孢囊线虫病的综合治理提供参考依据。     

火鹤花上的几种线虫鉴定

记述了从火鹤花根部分离鉴定的咖啡根腐线虫(Pratylenchuscoffeae)、食菌茎线虫(Ditylenchusmyceliophagus)、锡博尔滑刃线虫(Aphelenchoidescibolensis)、蘑菇滑刃线虫(A.composticola)和燕麦真滑刃线虫(Aphelenchusavenae)等5种植物线虫.     

2株真菌的鉴定及对禾谷孢囊线虫的防治效果

【目的】生防菌株的种类鉴定及对禾谷孢囊线虫Heterodera avenae的防治效果。【方法】以形态学特征和rDNA-ITS序列比对及系统发育树分析相结合的方法鉴定生防菌的种类,测定菌株A1和B1发酵液对孢囊、卵和2龄幼虫的活性及对小麦孢囊线虫病的盆栽防治效果。【结果】菌株A1和B1分别鉴定为寄生曲霉Aspergillus parasiticus和长枝木霉Trichoderma longilbrachiatum。处理14 d后,A1和B1的菌丝对线虫孢囊的寄生率可达80.00%以上。处理12 d后,菌株A1和B1的发酵液原液对卵孵化的抑制率分别为63.98%和67.56%,处理72 h后,对2龄幼虫的校正死亡率分别为68.14%和92.98%。盆栽试验发现,菌株A1和B1的3%菌肥培养物处理90 d后,孢囊减少率分别为31.71%和36.04%,小麦根长分别增加28.82%和59.62%,株高分别增加20.38%和21.43%。【结论】菌株A1和B1对禾谷孢囊线虫具有防治作用,是2株极具开发潜力的生防菌株。     

不同龄期和寄主植物对茄28星瓢虫药剂敏感性的影响

采用虫体浸渍法测定茄28星瓢虫(Henosepilachna vigintioctopunctata Fabricius )不同龄期幼虫和取食不同寄主植物的2龄幼虫对阿维菌素、氰戊菊酯和辛硫磷的敏感性.结果表明,取食龙葵的1～4龄幼虫随龄期增加耐药性增强,1～2龄幼虫对药剂最为敏感,到3龄后耐药性迅速增强.茄28星瓢虫2龄幼虫对阿维菌素敏感性以取食龙葵的最低,其它依次为马铃薯、番茄和茄子;对氰戊菊酯敏感性以取食马铃薯的最低,其它依次为茄子、龙葵和番茄;对辛硫磷敏感性以取食茄子的最低,其它依次为马铃薯、龙葵和番茄.     

小麦禾谷孢囊线虫在山东省的分布新报道

于2009年5～7月,在山东省13地级市61个县/区调查、采集小麦根系及根围土样本115份,在76份样本中检查到禾谷孢囊线虫(CCN)的孢囊,检出率为66.1%,孢囊密度为每200mL土壤0～326个。调查结果表明,CCN在菏泽、济宁、枣庄、聊城、济南、德州、滨州、东营、淄博、潍坊和青岛等11个地级市的47个县/区有发生,但发生状况在各地间差异很大:孢囊检出率前5位的是枣庄、聊城、青岛、济宁和菏泽,平均孢囊密度前5位的是聊城、青岛、德州、菏泽和东营;在13地级市的14个县/区未检查到孢囊,而在采自日照市和临沂市的7个县/区的15个样本中均没有检查到CCN孢囊。调查结果同时表明,CCN的远距离传播与跨区作业的联合收割机和河流的流水携带有关。有些小麦地块CCN孢囊密度很大,已成为当地小麦生产上新的危险性病害。     

4种禾谷孢囊线虫基因组DNA提取方法的比较和改进

用SDS-蛋白酶K裂解法(SDS-PK)、TE-蛋白酶K裂解法(TE-PK)、PCR buffer-蛋白酶K裂解法(PCRB-PK)和盐酸胍裂解法(Gu.HCl)提取禾谷孢囊线虫单个孢囊基因组DNA,以提取得到的基因组DNA为模板PCR扩增核糖体DNA(rDNA)片段,以扩增成功率和效率来反映基因组DNA提取的质量.结果表明:在所选的4种方法中,SDS-PK法扩增成功率最高,达85.71%,Gu.HCl法次之,TE-PK法最低.经微波裂解后,4种方法的DNA提取的成功率均有提高,其中微波裂解SDS-PK法为禾谷孢囊线虫单胞囊DNA提取的最优方法,PCR成功率可达96.97%.