不同种粒抗性大豆品种感染SMV后可溶性蛋白和游离氨基酸的研究

 采用感斑驳品种合丰25、丰收12,抗斑驳品种东农81-43、铁6915(东农),在隔离网室内进行盆栽试验,于对生真叶期分别接种SMV1号、3号株系,以未接种健株为对照,在鼓半粒期分析种皮游离氨基酸和可溶性蛋白含量。结果表明:抗斑驳品种健株种皮中可溶性蛋白含量显著高于感斑驳品种,说明种皮中可溶性蛋白含量与种粒抗性成正相关,可作为筛选抗斑驳品种的生化指标。感斑驳品种中未检测到甲硫氨酸,抗斑驳品种含有甲硫氨酸,甲硫氨酸能抑制色素的形成。接种SMV后,感斑驳品种种皮中可溶性蛋白含量增加,抗斑驳品种可溶性蛋白含量降低。感斑驳品种种皮中苏、苯丙、异亮、缬氨酸含量增加,抗斑驳品种上述氨基酸含量降低或维持不变。这些氨基酸能促进色素的形成,可能与种皮斑驳的形成有一定关系。     

影响大豆花叶病毒种子传毒和种子斑駁因素的研究

 本文研究了影响大豆花叶病毒种子传毒及种子斑驳的有关因素,以及种子传毒与种子斑驳的关系。结果表明,种子传毒率的高低受大豆品种,大豆花叶病毒(SMV)毒株,大豆感病早晚以及环境条件的影响。这些因素之间对种子传毒还存在交互作用。供试的12个大豆品种中,传毒率最高的为47%,最低的为25%;包括SMV Ⅰ,Ⅱ,Ⅲ号3个株系群的8个毒株在东农64-3513上传毒率的变化范围为1-33%,在抗霉2号上的变化范围为9-48%;大豆在开花以前感染SMV,种子传毒率可达45%,开花以后感病,种子基本不能传毒。
种子斑驳率因大豆品种,SMV毒株不同而异,并受品种与毒株交互作用的影响。种子斑驳既不代表种子带毒,也不代表种子传毒;从感病植株上采收的大豆种子,其斑驳种子与非斑驳种子的传毒率基本相同(P>0.05),因此,不能从种子斑驳率预测种子传毒率。     

大豆干种子中大豆花叶病毒的RT-PCR检测

 应用改进的SDS-酚氯仿法,在沉淀RNA前先加入1/4体积无水乙醇、1/10体积5mol/L乙酸钾沉淀多糖,然后再用异丙醇沉淀RNA,成功地从大豆干种子中提取了大豆花叶病毒(SMV)总RNA;应用RT-PCR技术对大豆种子中携带的SMV进行了检测,同时以DAS-ELISA方法作比较,建立了能直接以大豆干种子为检测对象的SMV快速、灵敏、特异的RT-PCR检测技术。     

大豆花叶病毒病研究进展

 大豆花叶病毒病是世界性病害,导致大豆产量降低并产生种粒斑驳。目前国内外对SMV株系的划分不统一。美国报道了G1-G7,G7A,C14九个株系,日本报道了A-E 5个株系,中国东北1、2、3号株系,江苏SA-SH株系,湖北S1,S2株系,黄淮Y 1-Y7株系。各地学者开展了抗源的鉴定和抗病育种工作,筛选和选育出一批抗病品种。美国已命名3个抗性基因,Rsv1,Rsv2,Rsv3。由于抗源不同,对中国东北3个株系SM V抗性遗传研究结果不同,抗性受1对或2对显性或隐性基因控制;对江苏株系抗性遗传研究结果一致,抗性受单显性基因控制。对感染SM V后大豆植株及种粒生理生化性状的变化及抗性机制进行了研究,表明过氧化物酶同工酶等性状与抗性有关。目前已鉴定出与抗性基因连锁的SSR,RFL P和R APD分子标记,成功的克隆了SMV外壳蛋白基因并导入大豆中。     

Temporal and Spatial Spread of Soybean mosaic virus (SMV) in Soybeans Transformed with the Coat Protein Gene of SMV

ABSTRACT Soybean lines transformed with the coat protein (CP) gene of Soybean mosaic virus (SMV) were evaluated for SMV resistance by quantifying the temporal and spatial spread of SMV strain AL-5 released from a point source in the field. The temporal spread of SMV within field plots during 1999 and 2000 was quantified by enzyme-linked immunosorbent assay. The Gompertz model most appropriately described temporal spread. Two SMV CP transformed lines (genotypes) had significantly lower infection rates and significantly lower final SMV incidence values (P 相似文献   

Soybean mosaic virus Helper Component-Protease Alters Leaf Morphology and Reduces Seed Production in Transgenic Soybean Plants

ABSTRACT Transgenic soybean (Glycine max) plants expressing Soybean mosaic virus (SMV) helper component-protease (HC-Pro) showed altered vegetative and reproductive phenotypes and responses to SMV infection. When inoculated with SMV, transgenic plants expressing the lowest level of HC-Pro mRNA and those transformed with the vector alone initially showed mild SMV symptoms. Plants that accumulated the highest level of SMV HC-Pro mRNA showed very severe SMV symptoms initially, but after 2 weeks symptoms disappeared, and SMV titers were greatly reduced. Analysis of SMV RNA abundance over time with region-specific probes showed that the HC-Pro region of the SMV genome was degraded before the coat protein region. Transgenic soybean plants that expressed SMV HC-Pro showed dose-dependent alterations in unifoliate leaf morphologies and seed production where plants expressing the highest levels of HC-Pro had the most deformed leaves and the lowest seed production. Accumulation of microRNAs (miRNAs) and mRNAs putatively targeted by miRNAs was analyzed in leaves and flowers of healthy, HC-Pro-transgenic, and SMV-infected plants. Neither expression of SMV HC-Pro nor SMV infection produced greater than twofold changes in accumulation of six miRNAs. In contrast, SMV infection was associated with twofold or greater increases in the accumulation of four of seven miRNA-targeted mRNAs tested.     

大豆花叶病种子带毒及介体传播在流行中的作用

 大豆植株的生育时期,对大豆花叶病的发展程度和危害性,有明显的影响。单叶期最感病,抗性随着生育年龄的增长而提高,单叶期潜育期最短、发病率最高,危害性最大。开花、结荚期后感病,对植株生长影响不大,黑龙江省大豆田出现的蚜虫中,大豆蚜、桃蚜、玉米蚜、棉蚜均能传播SMV,蚜虫最早出现于6月上中旬,高蜂为7月中下旬,大豆花叶病田间传播主要发生在7月中旬以后,8月为传播盛期,观察圃病害传播初期,病株有明显的梯降分布。与对照区呈鲜明对比,说明除早期形成的病苗外,没有其他的自源侵染,病害传播距离不远,多数在5-15米内,少有超过25米的,垅间和逆风向传播距离更短,种子带毒形成的病苗,在流行中起主导作用。蚜虫传播发生晚,主要引起种子斑驳。     

喷施外源GA对SMV侵染的野生大豆抗病性的影响

 大豆花叶病毒(SMV)是影响大豆生产的主要病害之一,在全球范围内对大豆生产造成影响。赤霉素(GA)是重要的植物激素之一,喷施外源GA对SMV侵染的野生大豆抗病反应的影响尚不清楚。通过测定喷施外源GA后接种SMV的野生大豆植株内源水杨酸(SA)含量,抗氧化酶活性及抗病基因表达,发现与对照相比,喷施外源GA的野生大豆植株的株高、根长、叶面积、植株干重、内源水杨酸含量、过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)活性及抗病相关基因GmPR-1、GmPR-10和GmNPR1的表达显著增加。说明在病毒侵染野生大豆之前喷施GA可以促进植株的生长,诱导植株抗病反应,降低病毒危害。     

喷施外源GA对SMV侵染的野生大豆抗病性的影响

 大豆花叶病毒(SMV)是影响大豆生产的主要病害之一,在全球范围内对大豆生产造成影响。赤霉素(GA)是重要的植物激素之一,喷施外源GA对SMV侵染的野生大豆抗病反应的影响尚不清楚。通过测定喷施外源GA后接种SMV的野生大豆植株内源水杨酸(SA)含量,抗氧化酶活性及抗病基因表达,发现与对照相比,喷施外源GA的野生大豆植株的株高、根长、叶面积、植株干重、内源水杨酸含量、过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)活性及抗病相关基因GmPR-1、GmPR-10和GmNPR1的表达显著增加。说明在病毒侵染野生大豆之前喷施GA可以促进植株的生长,诱导植株抗病反应,降低病毒危害。     

大豆褐斑粒与大豆花叶病毒若干株系的关系

 近年来发生的大豆褐斑粒是由大豆感染大豆花叶病毒的黄斑株系和顶枯株系等所致。人工接种上述病毒证明了这一点。种子斑驳的严重度与植株发病的严重度有某种相关性。
病株所结种子并不一定全部为褐斑粒。褐斑粒或病株所结无病状种子都可以传病,带毒种子产生疫苗的多少视环境条件、大豆品种及病毒的株系而异。     

大豆花叶病的流行因素及综合防治

1985年设置流行观察圃,以4个品种、4种播期、两种种子传毒率的种子,系统观察各因素对病害流行的作用。另设综合防治田,品种与观察圃相同;采取隔离种植、种传率低、适期播种及早期拔除病苗等措施。1986年用相同的4个品种,设5个隔离试区,各播种不同种传率(0—33％)的种子,测定播种种子传毒率对流行的影响。结果证明:传毒种子是当地最主要的侵染来源,田间杂草不传病,蚜虫传播距离多在100米以内,花期以后被侵染的植株,其种传率显著降低。播种种子传毒率与田间流行程度及收获种子传毒率相关显著。所用防病措施效果明显,可控制田间病情指数为4％、种传率为0％、种子斑驳率低于4％。     

Genetic Analysis of Soybean Plant Introductions with Resistance to Phytophthora sojae

ABSTRACT Phytophthora sojae, which causes Phytophthora root and stem rot of soybean, is a serious disease worldwide and is managed primarily by deploying cultivars with resistance. Thirty-two soybean plant introductions (PIs), all but three of which were from South Korea, were proposed as new sources of single-gene resistance to P. sojae. The objective of this study was to characterize the inheritance of resistance to P. sojae in these PIs. Twenty-two soybean populations from crosses of these PIs and the susceptible cv. Williams were inoculated with P. sojae OH17 (vir 1b, 1d, 2, 3a, 3b, 3c, 4, 5, 6, 7), and OH25 (vir 1a, 1b, 1c, 1k, 7). These isolates were selected because they are virulent on soybeans with all known Rps genes and many Rps gene combinations. Thirteen of the twenty-two populations had consistent segregation responses following inoculations between the two generations. In two PIs, resistance was conferred by two genes to OH17 and three genes to OH25. Resistance to both isolates was conferred by a single gene in PI 398440 although the individual families were not resistant to the same isolates. The data suggest that six of the populations have three-Rps gene combinations as previously proposed, while another four may have either a novel Rps gene or a four-Rps gene combination. Based on this phenotypic analysis, novel and uncharacterized Rps genes may be present in this material. More importantly, these PIs may serve as sources of novel Rps genes that can be used to more effectively manage Phytophthora root and stem rot.     

Pathogenesis of Alfalfa mosaic virus in Soybean (Glycine max) and Expression of Chimeric Rabies Peptide in Virus-Infected Soybean Plants

ABSTRACT Infection of soybean (Glycine max) plants inoculated with particles of Alfalfa mosaic virus (AlMV) isolate 425 at 12 days after germination was monitored throughout the life cycle of the plant (vegetative growth, flowering, seed formation, and seed maturation) by western blot analysis of tissue samples. At 8 to 10 days after inoculation, the upper uninoculated leaves showed symptoms of virus infection and accumulation of viral coat protein (CP). Virus CP was detectable in leaves, stem, roots, seedpods, and seed coat up to 45 days postinoculation (dpi), but only in the seedpod and seed coat at 65 dpi. No virus accumulation was detected in embryos and cotyledons at any time during infection, and no seed transmission of virus was observed. Soybean plants inoculated with recombinant AlMV passaged from upper uninoculated leaves of infected plants showed accumulation of full-length chimeric AlMV CP containing rabies antigen in systemically infected leaves and seed coat. These results suggest the potential usefulness of plants and plant viruses as vehicles for producing proteins of biomedical importance in a safe and inexpensive manner. Moreover, even the soybean seed coat, treated as waste tissue during conventional processing for oil and other products, may be utilized for the expression of value-added proteins.     

Alternative hosts and seed transmissibility of soybean blotchy mosaic virus

Soybean blotchy mosaic virus (SbBMV) is an important virus of soybean in the warmer regions of South Africa. The presence of the virus is associated with blotchy mosaic symptoms on soybean leaves and significant annual yield losses. The virus is a member of the genus Cytorhabdovirus and persists between soybean growing seasons. In this study, multiple specimens of indigenous tree species, other crops and herbaceous weeds surrounding soybean fields with high disease incidences of SbBMV were tested for the presence of SbBMV by RT-PCR in order to determine whether the presence of alternative hosts facilitates the seasonal carry-over of the virus. Commercial soybean cultivars commonly grown in the region were also evaluated for seed transmissibility of the virus. A total of 487 accessions representing 27 different species were screened and one accession each of Flaveria bidentis, Lamium amplexicaule and Gymnosporia buxifolia tested positive for the presence of SbBMV and may serve as possible alternative hosts of SbBMV, allowing over-wintering of the virus when soybean is absent. Symptoms associated with SbBMV infection were not present in any of the 2, 829 seedlings collected from naturally infected SbBMV plants, and none of the 21 seedlings showing various abnormalities and tested by RT-PCR were positive. SbBMV does not appear to be seed transmissible in soybean at an incidence above that which numbers screened would have detected the virus. It was concluded that the presence of alternative plant hosts, functioning as viral reservoirs during the soybean off-season might allow for the re-emergence of the disease early in the soybean production season each year. Future work will investigate the role of Peragallia caboverdensis, the leafhopper vector of SbBMV, and specifically the possible propagative transmission of the virus in the persistence of the disease.     

Quantification of within-field spread of soybean mosaic virus in soybean using strain-specific monoclonal antibodies

ABSTRACT Strain-specific monoclonal antibodies were used to follow the temporal increase and spatial spread of soybean mosaic virus (SMV) strain G-5 released from a point source. The use of strain-specific monoclonal antibodies allowed discrimination of within-field temporal and spatial spread of SMV strain G-5 from non-G-5 SMV isolates that originated from exogenous field sources. SMV isolates originating from exogenous sources have potential to alter the temporal and spatial pattern of within-field virus spread, which could potentially affect the choice of models used to quantify within-field pathogen spread. Analysis of SMV epidemics in field-plot experiments indicated that the logistic model was the most appropriate model to describe and compare the temporal spread of SMV among years. On the basis of ordinary runs analyses, within-field spread of SMV strain G-5 was random in 1991 and 1994, but was mostly aggregated in 1992 and 1993. Non-G-5 SMV isolates arising from exogenous sources displayed a random spatial pattern over time. This is the first study in which pathogen incidence (detection of SMV using strain-specific monoclonal antibodies) as opposed to disease incidence (based on symptoms) was employed to monitor and model SMV spread in time and space.     

Genetic and Phenotypic Analysis of Soybean mosaic virus Resistance in PI 88788 Soybean

ABSTRACT Resistance to Soybean mosaic virus (SMV) was identified in PI 88788 soybean, a germ plasm accession from China that is used widely as a source of resistance to soybean cyst nematode. Strains SMV-G1 through -G7 infected the inoculated leaves of PI 88788 but were not detected in upper, noninoculated trifoliolate leaves. Inheritance of resistance was determined by inoculating progenies of crosses of PI 88788 with susceptible cvs. Essex and Lee 68 with SMV strains G1 and G7. Allelomorphic relationships with known genes for resistance to SMV were tested in crosses with the resistant genotypes PI 96983, L29, and V94-5152, possessing Rsv1, Rsv3, and Rsv4 genes, respectively. Data analyses showed that resistance in PI 88788 to SMV-G1 is controlled by a single, partially dominant gene; however, to SMV-G7, the same gene was completely dominant. The PI 88788 gene was independent of the Rsv1 and Rsv3 loci, but allelic to Rsv4 in V94-5152. Expression of the Rsv4 gene in PI 88788 resulted in a reduced number of infection sites and restricted short- and long-distance movement of virus, rather than hypersensitivity. A unique late susceptible phenotype was strongly associated with heterozygosity. This gene has potential value for use in gene pyramiding to achieve resistance to several SMV strains, as well as for rate-reducing resistance.     

Molecular Marker Analysis of Soybean Plant Introductions with Resistance to Phytophthora sojae

ABSTRACT Molecular analysis of sources of resistance to plant pathogens should expedite and confirm novel gene discovery and consequently the development of disease resistant cultivars. Recently, soybean plant introductions (PIs) were identified that contain putative novel Rps genes for resistance to Phytophthora sojae. The number of resistance genes that confer resistance to P. sojae isolates OH17 (1b,1d,2,3a,3b,3c,4,5,6,7) and OH25 (1a,1b,1c,1k,7) was then determined in several of the PIs. The objective of this study was to determine if the Rps genes present in these PIs were associated with eight described Rps loci that have been mapped on soybean molecular linkage groups F, G, J, and N. Nine F(2:3) soybean populations were genotyped with simple sequence repeat (SSR) markers linked to previously mapped Rps loci. The nine PI populations all had SSR markers associated (P < 0.01) with resistance to P. sojae isolate OH17 in the Rps1 region. Rps1c is a likely candidate in eight PIs but novel genes may also be possible, while novel genes may confer resistance in one PI to P. sojae isolate OHI7. Two or more Rps genes, including some that are potentially novel, confer resistance to P. sojae isolate OH25 in eight of the populations. However, based on the response to these two isolates, virulence already exists for at least some of the novel genes identified in this study.     

Identification of a second Asian soybean rust resistance gene in Hyuuga soybean

ABSTRACT Asian soybean rust (ASR) is an economically significant disease caused by the fungus Phakopsora pachyrhizi. The soybean genes Rpp3 and Rpp?(Hyuuga) confer resistance to specific isolates of the pathogen. Both genes map to chromosome 6 (Gm06) (linkage group [LG] C2). We recently identified 12 additional soybean accessions that harbor ASR resistance mapping to Gm06, within 5 centimorgans of Rpp3 and Rpp?(Hyuuga). To further characterize genotypes with resistance on Gm06, we used a set of eight P. pachyrhizi isolates collected from geographically diverse areas to inoculate plants and evaluate them for differential phenotypic responses. Three isolates elicited different responses from soybean accessions PI 462312 (Ankur) (Rpp3) and PI 506764 (Hyuuga) (Rpp?[Hyuuga]). In all, 11 of the new accessions yielded responses identical to either PI 462312 or Hyuuga and 1 of the new accessions, PI 417089B (Kuro daizu), differed from all others. Additional screening of Hyuuga-derived recombinant inbred lines indicated that Hyuuga carries two resistance genes, one at the Rpp3 locus on Gm06 and a second, unlinked ASR resistance gene mapping to Gm03 (LG-N) near Rpp5. These findings reveal a natural case of gene pyramiding for ASR resistance in Hyuuga and underscore the importance of utilizing multiple isolates of P. pachyrhizi when screening for ASR resistance.     

大豆花叶病流行因素和发生预测研究

1984—1989年于济南研究诸因素对病害流行的作用。研究表明,大豆品种抗性和初始毒源数量为病害流行的主导因素。大豆幼苗期最感病,开花期为发病高峰。在春大豆苗期温度偏高雨量偏少及夏大豆苗期温度偏低雨量偏多的情况下,有利花叶病发生。对13种蚜虫进行饲毒接毒试验,证明桃蚜(Myzus persicae)、豆蚜(Aphis craccivora)和大豆蚜(Aphisglycines)可传毒,对病害田间流行有重要影响。对5年的16组数据应用IBM微机进行逐步回归和通径分析,组建发生预测模型。     

4种大豆种传病毒多重RT-PCR检测

进境大豆携带的病毒主要有菜豆荚斑驳病毒(BPMV)、烟草环斑病毒(TRSV)、烟草条纹病毒(TSV)和南方菜豆花叶病毒(SBMV)等,均为大豆种传病毒,可随大豆种子实现远距离传播。本研究对这4种大豆病毒的外壳蛋白基因部分序列设计引物,并通过优化引物、模板浓度和扩增参数,在一个体系中成功对4种病毒进行了多重RT-PCR扩增,得到307bp、206bp7、17bp5、18bp共4条特异性条带,建立了能同时检测BPMV、TRSV、TSV和SBMV的多重RT-PCR检测体系。该方法快速、灵敏、简便,同时特异性强,在出入境检疫中具有广泛的应用前景。