共查询到19条相似文献，搜索用时 468 毫秒
1.
为了明确甘肃天祝农牧区燕麦田孢囊线虫的发生情况及种类,2014年8-9月,采用Z字型取样法,对天祝燕麦主要种植区进行了调查。结果表明,采集到的80份燕麦根际土样中孢囊线虫发生率为44%,孢囊密度为4.3个·100g-1土样。安远镇的发生率最高,为54.2%,华藏寺的发生率最低,为14.3%。孢囊浅褐色,阔柠檬形,长571μm(447~727μm),宽449μm(375~595μm)。阴门双膜孔,膜孔长31μm(28~33μm),膜孔宽16μm(13~20μm),阴门裂长9μm(8~11μm),泡状突明显,未见阴门下桥。天祝5个乡镇孢囊线虫rDNA-ITS区片段长度均为1 045bp,经Blast比对发现,所测序列与燕麦孢囊线虫(Heterodera avenae)的ITS序列相似度达99%~100%。系统进化关系分析显示,天祝孢囊线虫与国内及国外燕麦孢囊线虫在同一个大的进化分支,与中国的燕麦孢囊线虫在同一个小的分支。因此,形态特征结合rDNA-ITS序列分析将甘肃天祝燕麦田的孢囊线虫鉴定为燕麦孢囊线虫。 相似文献
2.
为明确宁夏地区小麦田孢囊线虫分布情况及线虫种类,2015年8月,采用z字形取样法对宁夏5个地级市的14个县(市/区)小麦孢囊线虫的分布与发生情况进行了调查.结果发现,206份小麦根际土壤样本中,有98份检测出了孢囊,检出率为47.6％.被调查的14个县(市/区)小麦田均有禾谷孢囊线虫分布,其中固原市各县/区禾谷孢囊线虫的发生是首次报道.贺兰县的孢囊线虫检出率最高,达88.9％,彭阳县的检出率最低,为11.1％;14个县(市/区)依据孢囊线虫检出率的大小顺序为:贺兰县＞原州区＞西吉县＞中宁县＞永宁县＞青铜峡市＞平罗县＞同心县＞泾源县＞利通区＞惠农区＞隆德县＞海原县＞彭阳县.其中贺兰县、青铜峡市、同心县发生最严重,每100 mL土样孢囊数在20个以上的样品分别为5.6％、8.3％和11.1％.对所分离的主要线虫群体进行形态学显微观察和测量,并对其rDNA-ITS序列进行测定和聚类分析.结果表明,来自宁夏地区的小麦田孢囊线虫主要群体均为燕麦孢囊线虫(Heterodera avenae). 相似文献
3.
休闲与轮作对燕麦孢囊线虫种群动态的影响 总被引：4，自引：0，他引：4
为明确休闲与轮作对燕麦孢囊线虫病害的防治效果,通过盆栽模拟和田间试验相结合的方法,分析了土壤休闲、轮作和连作对燕麦孢囊线虫种群动态的影响。结果表明,燕麦孢囊线虫的孵化不受寄主或寄主种类的影响;不同处理土壤中二龄幼虫数量以及孢囊内的虫口密度变化趋势一致,河北地区燕麦孢囊线虫孵化高峰期主要在3-4月份。休闲一年后燕麦孢囊线虫的减退率为89.8%。小麦与茄子、甜瓜和冬瓜轮作一年后线虫减退率分别为93.8%、90.7%和90.7%,轮作二年后线虫减退率为98.8%。在自然病田,小麦连作一年后虫口密度上升36.8%,连作两年后虫口密度上升49.2%。说明小麦连作后燕麦孢囊线虫的发生呈上升趋势,休闲或轮作一年以上可有效地降低土壤中燕麦孢囊线虫的虫口密度。 相似文献
4.
为明确土壤中禾谷孢囊线虫(Heterodera avenae)初始密度(Pi)与小麦生长和产量的关系,在2011-2013年的两个冬小麦生育周期里,通过网室盆栽试验,分析了土壤禾谷孢囊线虫初始密度对其繁殖及小麦生长和产量的影响。结果表明,禾谷孢囊线虫的繁殖系数(Rf)随Pi的增加而减少,当Pi为0.5个卵·mL-1土时,Rf达到8.7;当Pi为64个卵·mL-1土时,Rf仅为2.8。小麦株高、茎叶干重、根干重及产量均与Pi呈显著负相关。当Pi≥8个卵·mL-1土时,小麦植株生长受到抑制,产量显著下降,因此田间禾谷孢囊线虫的初始密度高于该值时,应当采取有效措施进行防治。 相似文献
5.
禾谷孢囊线虫致病型的鉴定对于抗性品种的选育和利用非常重要。传统的致病型鉴定工序繁杂,费工费时。本研究共筛选147条随机引物,找到3个燕麦孢囊线虫荥阳群体致病型相关的RAPD标记,其中引物S10扩增出1条780 bp的多态性片段,S43扩增出1条1 300 bp的多态性片段,S112扩增出1条875 bp的多态性片段。这3个RAPD标记只在燕麦孢囊线虫荥阳群体上出现,而在黄淮麦区其他禾谷孢囊线虫群体不同致病型上均没有扩增条带,说明这3个RAPD标记确实是燕麦孢囊线虫荥阳群体致病型相关的分子标记,为下一步将RAPD标记转化为SCAR标记提供了依据,可以用于燕麦孢囊线虫荥阳群体致病型的检测和鉴定。 相似文献
6.
为给小麦孢囊线虫综合治理提供一定的理论依据,通过对苏皖鲁豫接壤地区30块田的调查和分析,探讨了这些地区麦田小麦孢囊线虫的发生情况及线虫群体之间亲缘关系。结果表明,采集的30份样品中都能检测到孢囊线虫,孢囊密度为每100g土壤1～80个。进一步对30个小麦孢囊线虫群体的rDNA-ITS区PCR扩增、测序,对其序列进行比较分析发现,30个分离物的核苷酸序列同源性为97.1%～100%,与已报道的中国菌株（AY148382,EU106175）、澳大利亚菌株（AY148395）和俄罗斯菌株（AY148351）群体的进化关系最为接近,且位于进化树的同一个分枝,都属于禾谷孢囊线虫Avenae组。 相似文献
7.
为给燕麦孢囊线虫的综合治理提供理论依据,在室内条件下分析了温度对燕麦孢囊线虫侵入、发育与孢囊形成的影响。结果表明,接种3d后,在18℃下燕麦孢囊线虫侵入数量最多;接种6～9d后,16℃处理的线虫侵入数量明显高于其他温度处理;在12、14℃下线虫侵入数量分别于接种15、12d达到最大值。在16～18、20、22、24℃下线虫完成生活史分别需要34、30、27和18d;在10～12℃下,于2个月后尚未发现雌虫形成。线虫在18～22℃下形成的孢囊数量最多。综合线虫的侵染数量与速度,认为线虫的最适宜侵染温度为16℃,最适宜的发育温度为18～22℃。 相似文献
8.
9.
10.
山东及河南濮阳禾谷孢囊线虫分布调查与rDNA-ITS-RFLP分析 总被引：1，自引：0，他引：1
为进一步明确山东省和临近山东的河南濮阳地区禾谷孢囊线虫病(Cereal cyst nematode,CCN)的发生状况及种类组成,于2013年6-8月,对山东省12个地级市124个点及河南省濮阳市19个点麦茬田采集的土样进行检测,分离孢囊,并通过rDNA-ITS-RFLP分析技术研究了山东省和河南省共15个禾谷孢囊线虫群体核糖体DNA(rDNA)内转录间隔区(ITS)的遗传变异。结果表明,山东省各县(市)的孢囊平均检出率为66.13%,河南省濮阳市的孢囊检出率为80.95%,其中山东聊城市和河南濮阳市发病相对较重;rDNAITS-RFLP鉴定结果表明,山东和河南两省的CCN为Heterodera avenae,不同地区CCN同源性高达99.8%以上,8种限制性内切酶AluⅠ、AvaⅠ、HaeⅢ、HindⅢ、HinfⅠ、RsaⅠ、PstⅠ、TaqⅠ共产生18个酶切片段,其中,AvaⅠ和HindⅢ不能酶切。酶切结果稳定,所有地区鉴定结果一致。 相似文献
11.
Observations on the prevalence and incidence of cereal cyst nematode (Heterodera avenae) in Scotland
A survey of the incidence of cereal cyst nematode (CCN) in Scottish cereal-producing land showed that 69% of fields contained CCN cysts and of these 54% contained eggs. CCN infestations were more frequent in SE and NE areas. Populations were small despite intensive cereal cropping, 71% having less than 1 egg/g soil and only 3% having more than 6 eggs/g soil. Soil type and cropping frequency were important in influencing the infestation of fields with CCN. Infested fields occurred most frequently in freely draining loamy-drift soils and populations were larger when these infested soils were cropped more frequently with cereals. In the soils that were less well draining, fewer infestations occurred and cropping frequency was less important, although cropping with oats in these soils was associated with larger CCN populations. A survey of seed-potato-producing land showed that 55% of fields known to contain CCN had viable populations but that population densities were smaller than in the more intensively cereal-cropped fields. 相似文献
12.
Abdollahi M 《Pakistan journal of biological sciences: PJBS》2008,11(14):1864-1867
During 2007 and 2008, soil samples of wheat and barley fields of the cold regions of the Kohgiluyeh and Boyer-Ahmad province were surveyed for cereal cyst nematode. In 65% of samples cysts were seen. Morphological and morphometrics of cysts, cone top structure and second stage juveniles of the isolated populations were studied. Detailed taxonomic studies revealed the existence of H. filipjevi. This is the first report of the species in the province. 相似文献
13.
青稞镰孢根腐病病原鉴定及致病性分析 总被引：1，自引：0，他引：1
为明确青稞镰孢根腐病的病原,于青稞苗期及成株期分别对甘肃省甘南藏族自治州合作市、临潭县和卓尼县等青稞主产区的根腐病发生情况进行调查并采集样品,采用常规的组织分离法分离其病原,结合形态特征和分子生物学进行病原鉴定,并用烧杯水琼脂法和盆栽法测定其致病性。结果表明,青稞镰孢根腐病在甘肃省甘南藏族自治州分布广泛,发病率在5%~20%之间。发病植株长势弱、发黄,茎基部缢缩、腐烂,穗白粒瘪,茎秆发褐或黑红。共分离得到88株青稞镰孢根腐病病原菌,苗期50株,成株期38株,经鉴定分别为燕麦镰孢Fusarium avenaceum、木贼镰孢F. equiseti、三线镰孢F. tricinctum、柔毛镰孢F. flocciferum、锐顶镰孢F. acuminatum及F. langsethiae。盆栽法和烧杯水琼脂法所测得的致病性差异显著,但均表明燕麦镰孢综合致病力较强,结合其分离率,确认燕麦镰孢为优势病原。 相似文献
14.
Populations (eggs/g dried soil) of the cereal cyst nematode Heterodera avenae Woll. failed to increase at two sites on susceptible spring barley but increased slightly at another on spring oats. Nematode multiplication was not related to the numbers of females produced on roots in summer; fewer female nematodes were produced where populations increased than where they declined. The failure of the nematode to multiply was due to few (less than 40%) of the females forming cysts containing eggs, a reduction in fecundity and an increase in the number of encysted eggs containing fungi. Verticillium chlamydosporium was the main fungus causing the decline in nematode numbers. Nematophthora gynophila was present at all sites but was most active at Woburn where irrigation was used to keep soils moist. V. chlamydosporium was the main parasite of encysted eggs at all sites but soil-borne saprophytic fungi were also isolated. These fungi were not found in many eggs and were considered to be only weak parasites. Differences in resting fungal spore densities in soil were not always related to differences in rates of parasitism. The activity of N. gynophila is affected by soil moisture and density of females as well as the density of spores in soil. The production of chlamydospores by V. chlamydosporium may also depend on the isolate of fungus present: some isolates produce no such spores on artificial media or, possibly, in soil. This work has shown that V. chlamydosporium and N. gynophila can reduce cereal cyst nematode populations under susceptible cereals but it is difficult to predict at present if they will give an effective control in a given soil or season. 相似文献
15.
Summary The sandy and sandy peat soils of the northeast of The Netherlands are mineralogically very poor and acid. Independently of
potato cyst nematode infestations, there is a considerable negative effect of increasing soil pH on potato tuber yield. Potato
cyst nematode infections aggravate the effect of soil pH in depressing yield. It was shown that both potato cyst nematode
infection and increasing soil pH values reduce the buffering capacity of the root system. Testing for yield as well as for
tolerance to potato cyst nematode infection should be made at a range of soil pH values, similar to those found in the target
area. This refers to active breeding programmes as well as to the selection of cultivars for yield trials. 相似文献
16.
黑龙江省大豆孢囊线虫（Heterod erag lyicines）生理小种分布的研究 总被引：3，自引：0，他引：3
本课题组对黑龙江省６５个市、县土样中存在的孢囊线虫，利用国际上通用的一套鉴别寄主，进行小种鉴定，共鉴定出６３个市县的孢囊线虫为３号小种，１个县为６号小种，１个县为７号小种，基本明确了黑龙江省大豆孢囊线虫生理小种类型与分布，为我省的抗线虫品种选育与合理布局提供了科学依据。 相似文献
17.
不同地区禾谷孢囊线虫对不同类型杀线剂的敏感性 总被引：1，自引：0，他引：1
为明确不同地区禾谷孢囊线虫对不同类型杀线剂的敏感性,采用浸渍法分别测定了灭线磷、噻唑膦、涕灭威、丁硫克百威、阿维菌素及甲维盐六种药剂对河南清丰、河北保定、安徽颍上、山东泰安和青岛五个地区的禾谷孢囊线虫二龄幼虫的室内毒力。结果表明,六种杀线剂对五个地区线虫的毒力表现为:甲维盐>阿维菌素>灭线磷>涕灭威>噻唑膦>丁硫克百威。灭线磷、噻唑膦、涕灭威和丁硫克百威对各地区线虫的LC50值都在582.7mg.L-1以上,不同地区线虫对同一药剂的敏感性存在一定差异,但相对毒力指数均在1.31以下;阿维菌素对各地区线虫的LC50值为26.0～66.3mg.L-1,甲维盐对各地区线虫的LC50值为20.1～35.3mg.L-1,不同地区线虫对这两种药剂的敏感性存在较大差异,相对毒力指数最高达2.55。 相似文献
18.
19.
《Field Crops Research》1996,47(1):33-41
Wheat (Triticum aestivum L.) production in some dryland regions is severely limited by the cereal cyst nematode (Heterodera avenae Woll.). Conventional fallow management during a wet period has been shown to allow hatching of the cysts during the fallow season and thereby sanitize the soil for the subsequent wheat crop. Recently a straw mulch (SM) management has been introduced into a long-term experiment in the Negev region of Israel. This management ameliorated the nematode damage and allowed continuous wheat production. Only three seasons of successful experimentation exist with the SM system so questions remain about its performance over seasons with differing weather conditions. A simple, mechanistic, wheat model was extended to simulate wheat development and growth when the crop is grown on nematode-infested soils. Incorporating statements describing inhibition of rooting depth as a result of nematode activity resulted in good agreement between simulations and 16 seasons of yield observations on continuous wheat. The effect of SM was simulated simply by decreasing soil evaporation and this resulted in higher levels of soil water and decreased nematode inhibition of rooting. Good agreement was obtained between the three seasons of experimental data and simulations of the SM system, with predicted grain yield within 10% of observations. Over 16 seasons, simulations of the SM system indicated substantial grain yield increases over continuous wheat in all but the highest-yielding season. Simulations in 14 seasons with conventional fallow management revealed that annual yields of SM were equivalent to biennial yields of the fallow system, resulting in a predicted doubling of wheat production for this dryland region of the Negev. 相似文献