燕麦胞囊线虫(Heterodera avenae Woll.)孵化特性研究

在室内离体条件下研究了低温预处理、植物根分泌物（包括寄主和非寄主）、溶液的ｐＨ值以及干燥等条件对燕麦胞囊线虫孵化的影响．结果表明：处于滞育期的胞囊经５℃低温预处理４周后，再置适宜的孵化温度（１５℃）即有幼虫孵出，低温处理的时间越长，孵化量越大；过低温度预处理（－１０℃）后，其孵化量明显低于５℃的处理．根分泌物既不能打破燕麦胞囊线虫的滞育，对处于孵化期胞囊内幼虫的孵出也无明显的刺激作用．在供试条件下，保湿液ｐＨ６时的孵化量最大，ｐＨ１２对幼虫的孵出有明显的抑制作用．干燥不利于幼虫孵化．     

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.     

Host status of Brachypodium distachyon to the cereal cyst nematode

Cereal cyst nematode(Heterodera avenae, CCN) distributes worldwide and has caused severe damage to cereal crops, and a model host will greatly aid in the study of this nematode. In this research, we assessed the sensitivity of 25 inbred lines of Brachypodium distachyon to H. avenae from Beijing, China. All lines of B. distachyon were infested by secondstage juveniles(J2s) of H. avenae from Daxing District of Beijing population, but only 13 inbred lines reproduced 0.2–3 cysts/plant, showing resistance. The entire root system of the infested B. distachyon appeared smaller and the fibrous roots were shorter and less numerous. We found that a dose of 1 000 J2s of H. avenae was sufficient for nematode infestation. We showed that Koz-1 of B. distachyon could reproduce more cysts than TR2A line. Line Koz-1 also supported the complete life cycles of 5 CCN geographical populations belonging to the Ha1 or Ha3 pathotype group. Our results suggest that B. distachyon is a host for CCN.     

麦类作物对燕麦胞囊线虫抗病性遗传研究进展

概述了燕麦胞囊线虫致病型、麦类人地燕麦胞囊线虫抗病必一鉴定方法，介绍了迄今世界上在麦类作物对禾谷囊线虫抗病育种中已选育和生产上正推广的一些主要抗病基因（品种），阐述了中国燕麦胞囊线虫致病型（特别对rDNA中ITS区的PCR－RFLP分析，所获得的一个新的ITS类型－ITS C)以及麦类作物品种抗性的研究现状，这对中国开展针对燕麦胞囊线虫的抗病育种及相关的研究有重要的意义。     

燕麦孢囊线虫江苏群体的孵化特征及致病型测定条件优化

在室内条件下测定了燕麦孢囊线虫江苏沛县闫集镇群体在不同处理温度和时间下的2龄幼虫孵化特征,同时评价了不同规格小麦种植容器和线虫接种密度对单株小麦白雌虫量的影响,优化了燕麦孢囊线虫致病型测定条件.结果表明:燕麦孢囊线虫江苏群体的孢囊经过低温刺激才能孵化出2龄幼虫.孢囊经5℃低温预处理8周后,在10、15和20℃条件下均能孵化,其中最适孵化温度为15℃,而25℃条件下仅有少量线虫孵化,28和30℃条件下线虫不能孵化.延长低温预处理时间有助于幼虫孵化.孢囊经14周低温预处理后置于15℃条件下,2龄幼虫的单周孵化高峰及累积孵化率均达到最高值,分别为322条和62％.2龄幼虫不同接种密度显著影响致病型测定中单株小麦白雌虫量,在不同规格的小麦栽种容器里每cm-3接种4条2龄幼虫时,单株小麦产生的白雌虫量最多.本研究优化的致病型生物测定条件,不仅可节约2龄幼虫接种量,而且可提高鉴别寄主抗感病评价的准确性.     

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.     

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%.     

安徽省小麦孢囊线虫的发生分布与鉴定

为了解小麦孢囊线虫(Cereal cyst nematode,CCN)在安徽省的分布和主要麦区CCN的种类,以及群体间关系,调查了淮北等麦区小麦根系白雌虫,用"Zig-Zag"法在怀远等地采集土样,用Fenwick&Oostenbrink法分离土样中的孢囊并孵化得2龄幼虫,利用孢囊阴门锥形态及de-man法鉴定CCN种类,扩增ITS特征片段,用MEGA5.05构建系统发育树。结果表明,安徽省52%采样点检出CCN,淮河以北采样点均检出CCN,江淮麦区7%的采样点检出CCN,长江以南麦区采样点未检出CCN。发生在怀远、凤台、灵璧、界首和颍上麦区小麦根际CCN鉴定为禾谷孢囊线虫(Heterodera avenae),淮河以北发生H.avenae麦区占淮北小麦种植面积的41.6%,另外,怀远H.avenae群体和其他群体亲缘关系较远,群体间形态有一定差异,但和亲缘关系差异无一致性。     

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）。     

宁夏地区禾谷孢囊线虫的发生与分布

采用随机抽样的方法,对宁夏回族自治区5个地区16个县(乡、镇)的小麦孢囊线虫病的分布和发生情况进行了调查,根据形态特征对孢囊线种类进行了鉴定.结果表明:危害宁夏小麦的孢囊线虫为禾谷孢囊线虫(Heterodera avenae Wollenweber);宁夏5个地区发生的禾谷孢囊线虫病均为该地区首次发现,调查地块的孢囊检...     

旱稻孢囊线虫的快速分子检测

根据旱稻孢囊线虫(Heterodera elachista)和常见孢囊线虫的ITS序列比对分析,设计1对旱稻孢囊线虫特异性引物He–F/He–R,特异性片段长度为281 bp。运用该特异性引物及建立的DNA提取方法和PCR体系,可特异性检测旱稻孢囊线虫单条2龄幼虫,可以从混合有1条旱稻孢囊线虫的0.1 g水稻根组织中特异性检测出目的DNA片段。特异性引物He–F/He–R与通用引物D2A/D3B结合,运用一步双重PCR检测方法可快速鉴定单孢囊,也可从初始分离的田间土壤总线虫样品中直接检测出旱稻孢囊线虫。     

大豆胞囊线虫病生物防治研究进展

大豆胞囊线虫病的生物防治是有效控制大豆胞囊线虫群体的重要措施。通过对各种生物防治方法的逐渐深入研究,生物防治这一措施将在大豆生产上有效控制大豆胞囊线虫的发生与为害发挥重要作用。对近年来沈阳农业大学植物线虫研究室及部分国内外的线虫研究室在大豆胞囊线虫病生物防治方面的研究进展进行了综述,研讨过去生防措施的利弊,探索大豆胞囊线虫病生物防治的新方法,为有效控制大豆胞囊线虫病开辟新的途径。     

二硫氰基甲烷与灭菌唑和吡虫啉的联合使用对小麦孢囊线虫的防治

在田间自然情况下测试2种主要成分为二硫氰基甲烷的新型种衣剂及其与常规种衣剂灭菌唑和吡虫啉的联合使用对小麦孢囊线虫的防治效果。播种前用种衣剂对小麦种子分别进行包衣处理。分别调查播种前、抽穗期和收获后土壤中的孢囊数量及单孢囊卵量的变化,同时对小麦抽穗期的株高和收获时的千粒重等进行测定。结果表明:测试种衣剂对小麦进行包衣处理后均对该处理小区的孢囊及单孢囊卵量有抑制作用,其中甘农Ⅲ号种衣剂单独使用和甘农Ⅲ号种衣剂+灭菌唑(0.5∶0.5)联合使用处理小区的单孢囊卵量减退率最高,防效分别达到37.59%和32.86%,实际增产率分别达到16.09%和26.40%;甘农Ⅲ号种衣剂+灭菌唑(0.5∶0.5)联合使用和甘农Ⅲ号种衣剂单独使用2个处理,对抽穗期白雌虫的抑制率最高,分别为72.27%和70.29%,对孢囊的防效分别达到51.61%和50.74%;甘农Ⅲ号种衣剂+灭菌唑(0.5∶0.5)联合种衣剂、甘农Ⅲ号种衣剂+吡虫啉(0.5∶0.5)联合种衣剂2个处理的小区增产效果显著高于其他处理,理论增产率分别达到40.35%和44.39%。甘农Ⅲ号种衣剂+灭菌唑(0.5∶0.5)联合种衣剂可有效防控小麦孢囊线虫病害,不仅降低了农药的使用量,同时也显著提高了小麦产量,适于在生产上推广应用。     

胶东地区不同麦田燕麦孢囊线虫群体发生量比较及差异分析

为探讨2015年燕麦孢囊线虫(Heterodera avenae,Ha)在胶东麦田的发生状况,在莱阳和即墨样田对Ha定点和定期取样,通过土壤中线虫分离和根组织中线虫染色后镜检,测定不同时期Ha各虫态群体密度及其动态变化.结果表明,在Ha 2龄幼虫土壤孵出量和根系侵入量上,莱阳样田均是即墨样田的1.4倍;在3龄幼虫和4龄幼虫发育量上,莱阳样田分别是即墨样田的1.8倍和1.7倍;在白色雌虫产生量上,莱阳样田是即墨样田的39倍;在Ha繁殖系数上,莱阳样田是即墨样田的6.5倍.有迹象表明,更加严重的土壤干旱状况是导致即墨样田Ha繁殖系数极其低下的原因.     

First report of cereal cyst nematode (Heterodera filipjevi) on winter wheat in Shandong Province,China

正The cereal cyst nematodes(Heterodera avenae,Heterodera filipjevi,Heterodera latipons)are considered to be one of the most important plant parasitic nematodes attacking most cereals and can cause significant crop losses(Sikora 1988).In China,H.filipjevi(Madzhidov 1981)Stelter,1984,was first reported from Henan province(peng et al.2010)and a few years later in Anhui province and Xinjiang Uygur Autonomous Region(peng et al.2016,2018).In December 2017,a survey for cereal     

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.     

Sampling Survey and Identification of Races of Soybean Cyst Nematode (Heterodera glycines Ichinohe) in Huang-Huai Valleys

Soybean cyst nematode (SCN Heterodera glycines Ichinohe) is one of the most important nationwide soybean diseases in China. A total of 38 soil specimens or locations in the area was sampled and tested for SCN races during 2001-2003 for the inspection of race distribution in Huang-Huai Valleys. A map of race distribution was constructed according to the data from both the present study and the published reports cited. Three areas, namely, the area of southeast to Jinan in Shangdong Province; the area of northern Henan Province and its border region to south of Hebei Province; and the area of Luohe, Zhoukou of Henan Province and Fuyang of Anhui Province mainly infested with Race 1 were identified. Race 4 was predominant in Shanxi Province, Beijing and the adjacent area of Henan, Shandong, and Anhui provinces, and the delta of Huanghe River in Shandong Province. Race 2 was mainly found in Liaocheng, Dezhou of Shangdong Province and Shijiazhuang of Hebei Province, and Jiaozuo and Huojia of Henan Province. Race 7 was distributed in the west part of Jiaodong Peninsula of Shandong Province and Kaifeng, Huaxian, Wenxian of Henan Province. Race 5 was found and scattered in Hebei and Henan Province. Race 9 was found in Shangqiu of Henan Province, which was reported for the first time in China. It can be seen that Race 1 and Race 4 were the two predominant races in Huang-Huai Valleys, and that research should focus on developing resistant cultivars of these races. There might exist other races in an area with some predominant races. The race substitution in the past decade was not obviously found, therefore, the results should be meaningful to future breeding for resistance to SCN in Huang-Huai Valleys.     

A fragment of a 70-kDa Heterodera glycines heat shock protein (HgHSP70) interacts with soybean cyst nematode-resistant GmSHMT08

Soybean cyst nematode(SCN) Heterodera glycines is considered as the major constraint to soybean production. Gm SHMT08 at Rhg4 locus on chromosome 08, encoding a serine hydroxylmethyltransferase, is a major gene underlying resistance against H. glycines in Peking-type soybeans. However, the molecular mechanism underpinning this resistance is less well characterized, and whether Gm SHMT08 could interact with proteins in H. glycines remains unclear. In this study, yeast two-hybrid screening was con...     

禾谷缢管蚜和麦长管蚜实验种群参数的差异

在室内自然变温（平均２０．２１℃）条件下，组建禾谷缢管蚜和麦长管蚜实验种群生命表。结果表明，禾谷缢管蚜的发育速率快，若蚜存活率高，有翅蚜比率明显偏低；禾谷缢管蚜和麦长管蚜的种群趋势指数（１）分别为５４．４０和３３．７０，净增殖率（Ｒｏ）、内禀增长力（ｒ＿ｍ）及周限增长率（λ）分别为５４．１５和３４．０、０．２４８６和０．１６８８及１．２８２２和１．１８３９．尽管这两种麦蚜成蚜期远长于若蚜期，但由于内禀增长力均相当大，使得稳定年龄分布中若蚜的比率分别高达９０．３５％和８９．３１％。