共查询到20条相似文献，搜索用时 15 毫秒
1.
Interaction of common bacterial blight bacteria with disease resistance quantitative trait loci in common bean 总被引：1，自引：0，他引：1
Common bacterial blight (CBB) of common bean (Phaseolus vulgaris L.) is caused by Xanthomonas campestris pv. phaseoli and X. fuscans subsp. fuscans, and is the most important bacterial disease of this crop in many regions of the world. In 2005 and 2006, dark red kidney bean fields in a major bean-growing region in central Wisconsin were surveyed for CBB incidence and representative symptomatic leaves collected. Xanthomonad-like bacteria were isolated from these leaves and characterized based upon phenotypic (colony) characteristics, pathogenicity on common bean, polymerase chain reaction (PCR) with X. campestris pv. phaseoli- and X. fuscans subsp. fuscans-specific primers, and repetitive-element PCR (rep-PCR) and 16S-28S ribosomal RNA spacer region sequence analyses. Of 348 isolates that were characterized, 293 were identified as common blight bacteria (i.e., pathogenic on common bean and positive in PCR tests with the X. campestris pv. phaseoli- and X. fuscans subsp. fuscans-specific primers), whereas the other isolates were nonpathogenic xanthomonads. Most (98%) of the pathogenic xanthomonads were X. campestris pv. phaseoli, consistent with the association of this bacterium with CBB in large-seeded bean cultivars of the Andean gene pool. Two types of X. campestris pv. phaseoli were involved with CBB in this region: typical X. campestris pv. phaseoli (P) isolates with yellow mucoid colonies, no brown pigment production, and a typical X. campestris pv. phaseoli rep-PCR fingerprint (60% of strains); and a new phenotype and genotype (Px) with an X. campestris pv. phaseoli-type fingerprint and less mucoid colonies that produced brown pigment (40% of strains). In addition, a small number of X. fuscans subsp. fuscans strains, representing a new genotype (FH), were isolated from two fields in 2005. Representative P and Px X. campestris pv. phaseoli strains, an FH X. fuscans subsp. fuscans strain, plus five previously characterized X. campestris pv. phaseoli and X. fuscans subsp. fuscans genotypes were inoculated onto 28 common bean genotypes having various combinations of known CBB resistance quantitative trait loci (QTL) and associated sequence-characterized amplified region markers. Different levels of virulence were observed for X. campestris pv. phaseoli strains, whereas X. fuscans subsp. fuscans strains were similar in virulence. The typical X. campestris pv. phaseoli strain from Wisconsin was most virulent, whereas X. campestris pv. phaseoli genotypes from East Africa were the least virulent. Host genotypes having the SU91 marker-associated resistance and one or more other QTL (i.e., pyramided resistance), such as the VAX lines, were highly resistant to all genotypes of common blight bacteria tested. This information will help in the development of CBB resistance-breeding strategies for different common bean market classes in different geographical regions, as well as the identification of appropriate pathogen genotypes for screening for resistance. 相似文献
2.
为研究国家作物种质库中保存菜豆种质携带种传菜豆普通花叶病毒（BCMV）的状况，根据BCMV的印基因序列设计一对特异性引物，从BCMV侵染的菜豆叶片上扩增出与理论大小一致的714bp的片段。在此基础上，应用改进CTAB法从菜豆干种子中提取总RNA并特异性扩增出相同大小的片段。对目的片段进行克隆、测序和序列同源性比较，结果表明，扩增片段的序列与其它BcMV的印基因序列同源性达88％-98％，确证该方法可以从莱豆干种子申直接检测BCMV。利用建立的方法，分别从单粒菜豆种子样本和30粒菜豆种子样本中检测到BCMV，其检测灵敏度较ELISA方法更高。来自河北的紫芸豆单粒种子带毒率高达100％，而在不同地理来源的6份菜豆种质中，4份被检出携带BCMV，表明入库保存的菜豆种质和种子已普遍为BCMV所侵染。 相似文献
3.
4.
MSMA-resistant (R) and -susceptible (S) biotypes of common cocklebur (Xanthium strumarium L.) were used to study PSI and PSII activities, and chlorophyll and carotenoid content of MSMA-treated and -untreated R and S biotypes. MSMA at 1, 10, and 100 mg/L did not inhibit either PSI or PSII activities. The R biotype had higher PSI and PSII activity than the S biotype with and without MSMA treatments. R biotype leaf discs had higher chlorophyll and carotenoid content than the S biotype after treatment with MSMA; the S biotype cotyldeons had higher levels of both pigments as compared to the R biotype cotyledons. MSMA induced a reduction in both pigments in S biotype cotyledons, and in young and mature leaf discs. Results indicate that photosynthetic capability might indirectly be involved in the resistance mechanism and carotenoids may protect against MSMA toxicity, possibly caused by an induced free radical mechanism. 相似文献
5.
6.
G. H. Boerema Adriana A. Verhoeven 《European journal of plant pathology / European Foundation for Plant Pathology》1972,78(1):1-14
An antibiotic substance, MYC 8005, was found to be produced by aStreptomyces strain, D197. It proved to possess strong antibiotic activities against bacteria, fungi and spider mites. It might be similar to antibiotic 323/58 reported in 1962 by Kruglyaket al. This antibiotic, however, is no longer available for comparison. The producing organism resmblesStreptomyces exfoliatus (Waksman & Curtis) Waksman & Henrici but differs from this species in the surface structure of the spores. For this reason it is proposed to give D 197 the nameStreptomyces exfoliatus var.echinosporus var. nov. The nature of the symptoms observed with spider mites and the susceptibility of various acaricide-resistant strains to this antibiotic suggest a new mode of action. 相似文献
7.
E. Drijfhout M. J. Silbernagel D. W. Burke 《European journal of plant pathology / European Foundation for Plant Pathology》1978,84(1):13-26
Pathogenicity and symptom expression of seventeen described isolates of bean common mosaic virus (BCMV) and five previously unreported isolates were compared on many bean cultivars (Phaseolus vulgaris L.). From these cultivars, a standard set of differentials were assigned to nine groups with different disease reactions. The twenty-two virus isolates comprised seven strain (pathotype) groups, three of which were divided into two subgroups each. To promote international standardization in BCMV research, recommendations are given for test conditions and procedures, criteria for strain differentiation, and maintenance of differential cultivars and virus strains.Samenvatting Zeventien beschreven stammen van het bonerolmozaïekvirus en vijf niet geïdentificeerde isolaten (Tabel 1) werden bestudeerd op een uitgebreide reeks van toetsrassen. De meeste van deze toetsrassen waren in de literatuur als zodanig vermeld, maar door de desbetreffende onderzoekers waren vaak verschillende series toetsrassen gebruikt, hetgeen de onderlinge vergelijking van de stammen bemoeilijkte.De bedoeling van dit onderzoek was: vergelijking en indeling van de virusstammen, samenstelling van een standaard-toetsrassenserie en het ontwerpen en beschrijven van werden zowel in Wageningen als in Prosser, Washington, USA, uitgevoerd met dezelfde virusisolaten en dezelfde zaadmonsters van de toetsrassen.De toetsrassen konden op grond van hun differentiële reacties na inoculatie met de virusstammen worden ingedeeld in negen groepen. De rassen binnen een groep hebben hetzelfde resistentiespectrum t.o.v. een standaardserie virusstammen. Uit elke groep werden op grond van hun geschiktheid (duidelijkheid en reproduceerbaarheid van de symptomen) één of meer vertegenwoordigers gekozen, waaruit een standaardserie van toetsrassen werd samengesteld (Tabel 2).De 22 stammen en isolaten werden op grond van hun pathogeniteitsspectrum t.o.v. de standaardserie van toetsrassen ingedeeld in tien groepen en subgroepen (Tabel 1). De stammen en isolaten binnen een groep of subgroep hebben eenzelfde pathogeniteitsspectrum (Tabellen 4 en 6) en worden op grond daarvan als identiek beschouwd. De differentiële reacties tussen de rassen van de standaardserie en de virusstammen en-isolaten zijn vermeld in de Tabellen 3 en 5. Voorgesteld wordt om de naam van de eerstbeschreven stam van iedere groep te handhaven en de andere stammen in een groep of subgroep op te vatten als isolaten daarvan.De toetsmethodiek wordt uitvoerig beschreven om standaardisatie van de stammenidentificatie te bevorderen. Ter verklaring van de in de literatuur gevonden tegenstrijdigheden in de differentiële reactie van de toetsrassen wordt een negental mogelijke oorzaken genoemd, o.a. het gebruik van planten van toetsrassen die reeds vanuit zaad met een onbekende stam waren besmet en het gebruik van onzuivere virusstammen (mengisolaten).De auteurs stellen zich verantwoordelijk voor het distribueren (op aanvraag) van kleine zaadhoeveelheden van de toetsrassen en, op beperkte schaal, van in zaad aanwezige zuivere virusstammen aan onderzoekers die betrokken zijn bij de identificatie van de stammen van dit virus. Bovendien zal zaad van de standaardserie van toetsrassen worden gedeponeerd in het National Seed Storage Laboratory te Fort Collins, Colorado, USA, terwijl de virusstammen (in zaad) in bewaring worden gegeven bij de American Type Culture Collection te Rockville, Maryland, USA, waar ze beschikbaar zullen blijven voor verder onderzoek. 相似文献
8.
G. H. Boerema Adriana A. Verhoeven 《European journal of plant pathology / European Foundation for Plant Pathology》1973,79(5):165-179
This list is a continuation of Series 1a (Neth. J. Pl. Path. 78, Suppl. 1, 1972), an account of the nomenclature of common parasitic fungi on trees and shrubs as used in official publications of the Netherlands Society of Plant Pathology and the Netherlands Ministry of Agriculture and Fisheries. 相似文献
9.
菜青虫 ( Pierisrapae Linne)又叫菜粉蝶 ,是凯里地区春夏甘蓝蔬菜上的主要害虫之一 ,笔者 2 0 0 2年 4～ 5月用 2 4 .5 %绿维虫螨乳油在凯里市郊大友庄村民组潘草龙家菜地进行了防治菜青虫试验 ,现将试验结果报告如下。1 材料与方法1 .1 供试药剂 :2 4 .5 %绿维虫螨乳油 (河北省徐水吉利仿生农药有限公司生产 ) ,40 %氧化乐果乳油(重庆农药厂生产 )。1 .2 供试作物 :结球甘蓝 (别名卷心菜、苞菜 )( Brassica oleracea var. capitata)。1 .3 试验方法 :选择在菜青虫发生严重的甘蓝菜地进行 ,虫龄多在 1～ 3龄期 ,设 2 4 .5 %绿维虫螨… 相似文献
10.
玉米瘤黑粉病抗病性研究 总被引：2，自引：1，他引：2
调查研究了沈阳地区田间玉米瘤黑粉病2004年自然发病情况,结果表明:供试的10个玉米品种的产量损失率为1%~10%,都是玉米瘤黑粉病的抗病品种;其中辽单37和辽单120是抗病品种,产量损失较大;新铁单10、沈农1号、丹玉90、铁单17和沈单12是中抗品种;铁单16、掖单2和沈单14是高抗品种,产量损失较小。玉米育种时,应当先从铁单16、掖单2和沈单14等抗病品种中选取,缩短育种周期,加快玉米品种的选育。 相似文献
11.
Phillip N. Miklas Lyndon D. Porter James D. Kelly James R. Myers 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(3):525-543
White mold, caused by Sclerotinia sclerotiorum, is a devastating fungal disease of common bean (Phaseolus vulgaris L.) worldwide. Physiological resistance and disease avoidance conferred by plant architecture-related traits contribute to white mold field resistance. Our objective was to further examine white mold disease avoidance in common bean. A comparative map composed of 79 quantitative trait loci (QTL) for white mold resistance (27), disease avoidance traits (36) and root traits (16) was generated. Thirteen white mold resistance QTL, six with strong and seven with weak associations with disease avoidance traits, were observed. Root length and lodging QTL co-located in three regions. Canopy porosity and height, and lodging were highly correlated with disease severity score in field screening trials conducted from 2000 to 2011. Resistance to lodging was extremely important for reducing disease severity in both dry and snap bean (r?=?0.61 across 11 trials). Avoidance traits were less effective in reducing disease severity in trials with heavy disease pressure. Dry bean lines with physiological resistance in combination with disease avoidance traits did not require fungicide application to protect yield potential under moderate and heavy disease pressure. Given the complexity of disease resistance as evidenced by the comparative QTL map, marker-assisted breeding for disease avoidance is not recommended at this time. Instead, selecting for resistance to white mold in the field, in combination with high yield potential and acceptable maturity, is the recommended strategy for improving both disease avoidance and physiological resistance to white mold in cultivars with commercially acceptable agronomic traits. 相似文献
13.
14.
15.
16.
Occurrence of Fusarium wilt of common heliotrope(Heliotropium europaeum L.) is reported. Pathogenicity of the causal agent was confirmed by reisolation from inoculated heliotrope plants. The specificity of the isolate was shown by cross-inoculation tests with five formae speciales and by inoculating the five respective hosts with a monoconidial isolate of the present fungus. Only the latter fungus was found to incite wilt in common heliotrope; the proposed name of this forma specialis isFusarium oxysporum f. sp.heliotropae nov. f. 相似文献
17.
Aflaq Hamid Mushtaq Ahmad B. A. Padder M. D. Shah Sehar Saleem T. A. Sofi A. A. Mir 《Phytoparasitica》2014,42(3):317-322
Bean common mosaic virus (BCMV), belonging to the family Potyviridae, is a serious pathogen of common bean (Phaseolus vulgaris L.) causing considerable economic losses owing to seed, sap and aphid transmissibility. The viral nature of the test isolates and identity of the virus as BCMV were confirmed by mechanical transmission and DAS-ELISA using BCMV antiserum. Pathogenic variability studies in BCMV infecting common bean (Phaseolus vulgaris L.) in Jammu and Kashmir (a northwestern Himalayan state of India), revealed the existence of three pathogroups – PG-I, PG-II and PG-VII, accommodating five strains (NL-1, NL-1n, NL-4, NL-7 and NL-7n). Comparative sequence analysis of coat protein gene revealed that the strains NL-1, NL-4 and NL-7 shared more than 90% amino acid sequence homology with other BCMV isolates from other countries. DAG motif as well as BCMV specific conserved motif MVWCIDN were present in all the three strains. Phylogenetic analysis of coat protein also clustered them in the BCMV group. This study confirmed the occurrence of BCMV and its strains on common bean in Kashmir. 相似文献
18.
19.
为了筛选对螺旋粉虱有较强生物活性的化学药剂,以螺旋粉虱成虫为试虫,采用叶片浸渍法对15种常用杀虫剂进行筛选,并对较为敏感的药剂进行室内毒力测定及田间防效评估。室内毒力测定结果表明,虫螨腈、辛硫磷对螺旋粉虱成虫活性较为显著,LC50分别为0.881mg/L和1.055mg/L,甲氰菊酯、异丙威对螺旋粉虱若虫活性较为显著,LC50分别为5.320mg/L和9.425mg/L。在田间药效评估中,甲氰菊酯、虫酰肼、异丙威、氟铃脲在各供试浓度下对螺旋粉虱均表现出较好活性,药后144h,125mg/L浓度田间防效均在80%以上。上述结果表明,甲氰菊酯、虫酰肼、异丙威、氟铃脲对螺旋粉虱具有较好的防治效果,在进行螺旋粉虱的田间防治中,可用这几种药剂进行交替使用,防止抗性的产生。 相似文献
20.
Shaner DL 《Pest management science》2004,60(1):17-24
Most modern herbicides have low mammalian toxicity. One of the reasons for this safety is that the target site for the herbicides is not often present in mammals. There are approximately 20 mechanisms of action that have been elucidated for herbicides. Of these, some do share common target sites with mammals. The mechanisms include formation of free radicals, protoporphyrinogen oxidase (PROTOX), glutamine synthetase (GS) and 4-hydroxyphenylpyruvate dioxygenase (HPPD). PROTOX, HPPD and GS inhibitors have been shown to inhibit these enzymes in both plants and mammals and there are measurable effects in mammalian systems. However, the consequences of inhibiting a common target site in plants can be quite different than in animals. What may be a lethal event in plants, eg inhibition of HPPD, can have a beneficial effect in mammals, eg treatment for tyrosinemia type I. These chemicals also have low mammalian toxicity due to rapid metabolism and/or excretion of the herbicide from mammalian systems. 相似文献