共查询到19条相似文献，搜索用时 218 毫秒
1.
大豆灰斑病叶部病害普遍率与严重度关系初步探讨 总被引：1，自引：0，他引：1
1992~1995年在田间接种条件下对大豆灰斑病叶部发病情况进行系统调查,获得86组感病品种(合丰22)和66组抗病品种(合丰25)普遍率与严重度间对应关系数据,在计算机上分析了两者的关系(I-S关系)。结果表明,感病品种和抗病品种叶部病害的I-S关系均可用直线方程描述,其直线回归方程分别为:#br#SS感=-2.8029+0.5252IS±6.4364(SS、IS-感病品种严重度和普遍率)#br#SR抗=-0.3843+0.6334IR±3.7679(SR、IR-抗病品种严重度和普遍率)#br#协方差分析结果表明,大豆品种的抗病性对大豆灰斑病叶部病害的I-S关系有一定影响。 相似文献
2.
小麦叶锈病、白粉病和条锈病普遍率与严重度间的关系 总被引：4，自引：2，他引：4
在田间接种条件下,详细地观察了小麦叶锈病、白粉病和条锈病普遍率与严重度之间的关系(I-S关系)。结果表明供试三种病害的I-S关系均可用指数函数描述;在普遍率小于70%左右时,用直线方程拟合效果更好;普遍率大于90%时,对严重度的预测效果较差。分别建立了各病的I-S关系式。小麦生育阶段(拔节期、抽穗开花期、灌浆期)对叶锈病和白粉病I-S关系没有明显的影响,而条锈病的I-S关系在不同生育阶段有一定的差异。文章最后对I-S关系的使用进行了讨论。 相似文献
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我国植病检疫的现状与进展 总被引：2，自引：0，他引：2
植物检疫性病害是破坏性大、流行性强、大多可经多种途径传播,并对农业生产造成灾害性后果的外来危险性病害。我国对植病检疫工作十分重视,为防止检疫性病害的传播为害,制定了一系列严格的检疫规定和措施,对重要的检疫性病害的流行规律、传播机制、检测技术、检疫处理方法的研讨和应用取得了很大的进展。 相似文献
5.
植物病害普遍率和严重度的关系研究 总被引：2，自引：1，他引：2
本文探讨了植物病害普遍率与严重度关系(I…S),并根据单利式和复利式病害的流行特征,提出了以下二个模型:(1) S=Smax/[1+a (1-I)b](2) S=Smax/[1+a ((1-I)/I)b]这里,a、b均为大于零的常数,Smax为严重度的最大值,小于或等于1。文中对单季稻纹枯病,小麦赤霉病和油菜菌核病等的多组I…S关系数据进行拟合,并与Gompertz衍生模型(王振中等,1987)作了比较,表明(2)式拟合效果最佳。 相似文献
6.
稻粒黑粉病(病原菌Neovossia horrida (TaK.)Padw. et A. Kahn)是杂交稻繁殖制种田不育系上的主要病害,流行频率高,危害损失大。普遍率和严重度的关系(I-S关系)是植病流行学观测技术上的一个重要问题。 相似文献
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预测(prediction)和预报(forecast)可以作为同义词使用,二者都是对某些事物未来事实的预述。混乱的是,对未来病害爆发的预报通常根据对过往危险期的观察。就病害的侵染而言,这样的预报是后于现实,而针对病害爆发则又是先于现实。有时用监测(detection)一词来表述病害侵染后的 相似文献
8.
用于病害防治的尖端技术涉及领域较广,本文仅就生物工程学尖端技术应用于病害防治的开发研究和问题进行叙述。生物工程学与病害防治有直接关系的是微生物利用、重姐DNA、细胞融合及组织培养等。这些技术被应用在<1>制作弱毒病者;<2>拮抗微生物利用;<3>培育抗性品种等各领域。 相似文献
9.
烟草花叶病普遍率与严重度的关系及感病品种与转基因抗病品系间的比较 总被引：2，自引：1，他引：2
利用田间调查取得的数据,分析了烟草花叶病在转基因抗病品系上和感病对照品种上的普遍率与严重度的关系(I-S)。结果表明感病品种的I-S关系以指数函数拟合较好;在普遍率小于35%左右时可以用直线方程(b1)拟合。在转基因抗病品系上I-S关系呈现为直线方程(b2)。b1、b2两直线方程的斜率不同,感病品种的斜率显著大于转基因抗病品系的。根据两品种(系)间的I-S关系的显著差异,从流行学角度探讨了转基因抗病品系对压低流行强度的作用、并分别用抗感品种(系)建模以外的另一种数据对利用普遍率估测严重度的可行性进行验证,抗感品种(系)预测的平均准确度分别为85.9%和83.3%。 相似文献
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作者对田间自然发病情况的观察和盔栽接种试验,获得92组叶稻瘟和80组穗颈稻瘟普遍率和严重度间对应关系的数据,在计算机上分别分析了叶瘟和穗颈瘟普遍率与严重度之间的关系(I-S)。结果表明:叶瘟I-S关系和穗颈瘟I-S关系均可用直线方程描述,其直线回归方程为:叶瘟:SL=-1.104+0.455IL(SL,IL——叶瘟严重度和普遍率)穗颈瘟:SE=-3.717+0.737IE(SE,IE——穗颈瘟严重度和普遍率)协方差分析结果表明:水稻品种的抗病性对稻瘟病 I-S 关系有一定影响。 相似文献
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中国茶树炭疽菌属病害研究进展及展望 总被引：1，自引：0，他引：1
茶树是一种重要的经济作物,广泛种植于热带和亚热带地区。随着茶产品经济价值的提高,茶叶生产安全备受关注。炭疽菌是引起茶树病害的病原菌之一,严重影响茶叶产量和茶产品品质,威胁我国茶产业的良性发展。利用抗病品种是防治茶树病害最为经济、有效的措施。目前,茶树炭疽菌种名使用混乱,茶树与炭疽菌的互作研究也较为薄弱,而简单依靠药剂防治病害也对茶叶质量安全造成一定的影响。本文梳理并明确了危害茶树的炭疽菌种类;总结了现有的茶树和炭疽菌互作的研究成果,提出识别免疫(effector triggered immunity,ETI)模式是茶树防御炭疽菌的主要机制;对茶树病理学存在的问题进行了归纳并提出解决办法,并展望了深入开展茶树抗病机理研究的思路,以期为制定茶园绿色防控技术及选育茶树抗病良种提供科学参考。 相似文献
12.
雪松疫霉(Phytophthora lateralis)的快速分子检测 总被引：1，自引：0，他引：1
由雪松疫霉(Phytophthora lateralis)引起的疫病是一类植物检疫性病害。为建立该病原菌的快速检测技术,本文比较分析了雪松疫霉和其他疫霉的tRNA序列,在此基础上设计了一对检测雪松疫霉的特异性引物T1/T2,该对引物从雪松疫霉中扩增得到1条192 bp的条带,而其他15种疫霉和其他真菌菌株均无扩增条带,表明该对引物对雪松疫霉具有特异性。在25μL PCR反应体系中,引物T1/T2检测灵敏度为10 pg基因组DNA;而以引物T3/T4和T1/T2进行巢式PCR扩增,能够检测到1 fg基因组DNA,使检测灵敏度提高了10 000倍。该检测体系对灭菌水中游动孢子的检测灵敏度可达0.5个游动孢子,对人工接种发病的植物组织能够特异性地检测到该病原菌。此外,进一步建立了该病原菌的实时荧光定量PCR检测体系。 相似文献
13.
The development of plant diseases is associated with biophysical and biochemical changes in host plants. Various sensor methods have been used and assessed as alternative diagnostic tools under greenhouse conditions. Changes in photosynthetic activity, spectral reflectance and transpiration rate of diseased leaves, inoculated with Cucumber mosaic virus (CMV), Cucumber green mottle mosaic virus (CGMMV), and the powdery mildew fungus Sphaerotheca fuliginea were assessed by the use of non‐invasive sensors during disease development. Spatiotemporal changes in leaf temperature related to transpiration were visualized by digital infrared thermography. The maximum temperature difference within a leaf was an appropriate parameter to differentiate between healthy and diseased plants. The photosynthetic activity of healthy and diseased cucumber plants varied as measured by chlorophyll fluorescence and compared to the actual chlorophyll content. Hyperspectral imaging data were analysed using spectral vegetation indices. The results from this study confirm that each pathogen has a characteristic influence on the physiology and vitality of cucumber plants, which can be measured by a combination of non‐invasive sensors. Whereas thermography and chlorophyll fluorescence are unspecific indicators for plant diseases, hyperspectral imaging offers the potential for an identification of plant diseases. In a sensor data fusion approach, an early detection of each pathogen was possible by discriminant analysis. Although it still needs to be validated under real conditions, the combination of information from different sensors seems to be a promising tool. 相似文献
14.
Remedios Villajuan-Abgona Koji Kageyama Mitsuro Hyakumachi 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(3):227-235
Three isolates of binucleateRhizoctonia (BNR) were tested for biological control of damping-off of cucumber seedlings caused byRhizoctonia solani AG 2-2 and AG 4. BNR isolates L2 (AG Ba) and W1 and W7 (AG A) provided protection of 58 to 71% against virulent isolate C4 of AG 4 and 64 to 75% protection against virulent isolate RH 65 of AG 2-2. Varying protection was provided to the seedlings by the BNR isolates against the virulentR. solani from the two AGs depending on their combination. The BNR isolates did not vary in providing protection to the seedling when tested against virulent C4 when both isolates were inoculated using three different methods,viz. in water agar, combination of water agar and soil and using soil alone. Protection of 58 to 71 % was provided by the isolates when inoculation was done on the hypocotyl using water agar, 62.8 to 75% using the combination of water agar and soil, and 75 to 85% when inoculation of both isolates was done in soil. Pre-incubation of BNR W7 or delayed inoculation of C4 (from 0.5 day to longer duration) using the different methods provided an increased protection to the seedlings to give complete inhibition of damping-off disease. Simultaneous inoculation of both BNR W7 and C4 using the three methods failed to provide protection to the seedlings. Among the BNR isolates, BNR W7 showed plant growth promotion in terms of significant increase in plant height (P=0.01) and fresh weight (P=0.05). 相似文献
15.
Plant Viruses Transmitted by Thrips 总被引：8，自引：0，他引：8
Jones David R 《European journal of plant pathology / European Foundation for Plant Pathology》2005,113(2):119-157
All thrips (order Thysanoptera) that are known to be vectors of plant viruses are identified and described. Thrips transmit
plant viruses in the Tospovirus, Ilarvirus, Carmovirus, Sobemovirus and Machlomovirus genera. Tospoviruses are the cause of a number of significant emerging diseases, such as capsicum chlorosis and scape blight
of onion. They infect thrips as well as plant hosts and the relationship between pathogen and vector is intimate. Once infected
at the larval stage, adult thrips usually transmit tospovirsuses for life. Transmission to plant hosts occurs when thrips
feed. Information on the distribution and hosts of all recognised thrips vectors is provided. Fourteen tospovirus species
are described with information provided on other tospoviruses that have not yet been designated as species. The history of
the research that has led to present knowledge is reviewed in chronological order for each tospovirus. The possible origin
of tospoviruses is discussed. Information is presented on viruses, which are thrips-transmitted by mechanical processes, in
other genera. Pathways of spread of thrips vectors in relation to the threat of tospoviruses to European agriculture are discussed. 相似文献
16.
Root infection of potato by Spongospora subterranea: knowledge review and evidence for decreased plant productivity 
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下载免费PDF全文 R. E. Falloon U. Merz R. C. Butler D. Curtin R. A. Lister S. M. Thomas 《Plant pathology》2016,65(3):422-434
Information is reviewed on root infection of potato by the plasmodiophorid Spongospora subterranea f. sp. subterranea. This pathogen has long been recognized as the cause of root galls (hyperplasia) and the economically important disease powdery scab on tubers (modified stolons). The significance for plant productivity of the zoosporangium stages of the pathogen in potato roots has only recently begun to be documented. Two experiments are described that assessed effects of S. subterranea root infection on potato plant root function and productivity. A greenhouse experiment measured root function and plant parameters for eight potato cultivars with markedly different susceptibilities to tuber powdery scab. Water uptake and plant growth were reduced by S. subterranea inoculation in all eight cultivars. The magnitudes of these negative effects, and intensities of root hyperplasia, differed among the cultivars, but were not related to respective susceptibilities to tuber powdery scab. A field trial assessed root function and plant productivity for a cultivar (Iwa) that is very susceptible to Spongospora tuber and root diseases. Soil water content beneath uninoculated plants was consistently less than for inoculated plants, indicating that inoculation reduced water uptake (root function). Inoculation reduced shoot and root dry weights, and reduced weight of tubers per plant by 42%. Spongospora subterranea causes three diseases of potato: root membrane dysfunction, root hyperplasia and tuber powdery scab. The root diseases caused by the pathogen are likely to be important both for powdery scab management and for deleterious effects on potato crop yields. 相似文献
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为有效防治由不同类型卵菌引起的植物病害,该研究对数据库中的霜霉、疫霉和腐霉3类不同卵菌的全基因组数据进行序列特征分析、同源性分析和共线性分析以及同源差异基因富集通路分析。结果显示,霜霉、疫霉和腐霉来自独立的谱系,且疫霉与霜霉的亲缘关系较近;疫霉的致病相关基因数量最多,主要有RxLR、CRN、NPP、NF和PcF基因家族,霜霉的致病相关基因数量次之,腐霉的致病相关基因数量最少;3类卵菌共确定了13 392个同源基因,其中3类卵菌均共有的同源基因为3 786个,不同菌种的同源基因数量差异较大,整体表现为疫霉>霜霉>腐霉;同源差异基因富集程度最高的前20个通路主要是基础代谢的通路和中间代谢通路,其中抗坏血酸和藻酸盐代谢、ABC转运蛋白和果糖和甘露糖代谢相对富集程度较高,基因数目也较多。 相似文献
18.
Aspects of the population: dynamics of Striga hermonthica (Del.) Benth. on pearl millet (Pennisetum americanum (L.) K. Schum.) were studied in Sahelian Mali. Seasonal development was recorded and density-dependent mortality and fecundity in post-emergent populations investigated. An attempt was also made to assess yield loss due to S. hermonthica attack using a regression approach. The first S. hermonthica plants emerged 42 days after crop germination, and the minimum time to complete the life cycle from emergence was 56 days. Results indicated a premature mortality of 66% in emerged populations. The growth stage reached by the time of host plant death appeared to be important in determining survival to maturity, premature mortality being greatest in plants that had not reached flowering by this time. The potential seed output per plant was estimated at 10 985. There was no evidence that the fecundity of S. hermonthica was affected by the density of emerged populations. Regression models showed a significant relationship between millet yield and emerged S. hermonthica density. The results suggest that lower densities give a relatively larger decrease in yield per S. hermonthica plant. The results of the study are discussed in relation to their implications for control. 相似文献
19.
植物内生枯草芽孢杆菌Em7菌株对葡萄灰霉病菌的抑菌活性 总被引：2，自引：0，他引：2
通过室内皿内对峙抑菌试验、分生孢子萌发抑制试验、离体果实接种试验以及电镜技术,研究测定了分离自小麦根部的植物内生枯草芽孢杆菌Em7菌液对葡萄灰霉病菌Botrytiscinerea Pers.的抑制作用及抑菌机理。结果表明:用Em7菌液处理葡萄灰霉病菌后,在PDA培养基上形成了明显的抑菌圈,直径达2.81 cm;菌液对分生孢子萌发的抑制率达到88.65%;经Em7菌液处理后,离体果实病情指数明显低于空白对照,相对防治效果达到78.92%。电镜观察发现,处理组菌丝生长异常,体表凹凸不平,局部膨大成结或缢缩,分枝变多,菌丝体内液泡增多,细胞壁增厚,细胞膜透性发生变化。表明植物内生枯草芽孢杆菌Em7菌株对葡萄灰霉病菌有良好的抑制作用,并且可以有效控制葡萄灰霉病的发生。 相似文献