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1.
福建稻瘟菌毒性类型组成及其对水稻几个Pi基因的毒性频率 总被引：7，自引：2，他引：7
稻瘟病是福建省水稻生产中的重要病害之一,系统掌握稻瘟菌毒性类型组成和变化动态及其与主要抗病基因的互作特点,是制定抗病品种选育与合理利用的依据。本研究根据稻瘟病菌与6个CO39近等基因系品种互作亲和性的结果,将1995~2001年从福建采集分离的398个有效单孢菌株区分为26个毒性类型,其中毒性类型I34.1出现频率最高,为优势毒性类型,出现频率较高的还有I20.1、I04.1、I24.1、I0.1、I30.1等;结果还发现福建稻瘟菌群体对Pi1和Pi2毒性频率较低,分别为7.53%和11.31%,特别是对Pi1和Pi2基因联合毒性频率仅2.76%,说明在水稻抗瘟育种中可以考虑将Pi1和Pi2基因累加利用。 相似文献
2.
稻瘟病是水稻生产上的重要病害,了解稻瘟病菌群体毒性组成是水稻抗病品种合理布局的重要基础。2012-2015年从湖南桃江病圃中不含已知抗瘟基因的水稻品种‘丽江新团黑谷’上成功分离出351个稻瘟病菌单孢菌株,在温室于水稻5叶期采用离体接种法测定了其对24个水稻抗稻瘟病单基因系的毒性,结果表明,病圃中稻瘟病菌以广谱强致病性的菌株为主,病菌对不同抗瘟基因的毒力频率在50.56%~96.67%之间,而不同年度间对24个抗性基因均具毒性的菌株出现频率在0~15%之间。对2015年的每2个抗瘟基因的联合毒力分析表明,基因两两搭配后的联合抗病系数最高、联合致病系数最低的组合是Pi-3*Pi-k(RAC=0.19,PAC=0.43)。 相似文献
3.
稻瘟病是我县的重要病害,叶瘟的发展对穗瘟具有一定的作用,但早、晚季有明显差异。笔者根据我县1971-1990年稻瘟病发生情况,计算出早稻穗瘟和叶瘟关系(晚稻不显著)。 穗瘟率和叶瘟率: y=-1.4887 0.8769x R=0.7663 相似文献
4.
水稻品种的抗性鉴定:1973～1977年在稻瘟病圃中,筛选出对穗颈瘟4～5年保持中抗以上的品种15个,1975～1977年又鉴定出对穗颈瘟3年均保持中抗以上的品种47个。在病圃中对大量水稻品种抗性鉴定材料的统计分析表明,籼稻品种的叶片对稻瘟病菌抗侵入和抗扩展能力强的品种数量比粳稻多。穗颈和主轴则不同,在病圃中粳稻叶瘟发生较重的年份,籼稻抗侵入的品种数量比粳稻多,反之,籼稻比粳稻少。但在同一抗病等级中,粳稻造成的损失多比籼稻轻,表现耐病性强的品种数量比籼稻多。根据多年和多点试验,绝大部分品种在不同地区和不同年份之间抗性表现不一致。就叶瘟和穗颈瘟抗性变化情况相比,叶瘟抗性变化较穗颈瘟大。 相似文献
5.
有关稻瘟病的测报研究,已有很多报道,本工作设计利用区域内稻瘟病在不防治情况下的自然发病状况这一内在的生物因素来开展短期测报,并通过对几年来资料的分析找出了一些相关规律和测报参数,作为大田测报应用指标。一、材料与方法选择稻瘟病常发地区,持续五年设立病圃,进行多品种(系)系统定点,定时观察,共调查了176份早稻材料的叶瘟、穗瘟在不防治情况下的自然发病情况,叶瘟的调查于5月18至 相似文献
6.
稻瘟病(Pyricularia oryzae)和白叶枯病(Xanthomonas campestris PV.oryzae)是我国水稻的两个重要病害,常同田发生,培育和筛选双抗品种,为兼治两病最经济有效的措施。作者1975年从国外引进452个品种(系),经病圃和人工接种鉴定,初步筛选出75个抗叶瘟和穗颈瘟的品种,后经8年对稻瘟和白叶枯病的抗性鉴定及株选,至1984年选出抗两病的中迟熟品种12个(称“双抗品种”)。1985年从中选出7个参加全国水稻 相似文献
7.
宁夏稻区年雨量200—300毫米,主要集中在7、8、9三个月。水稻于5月底或6月初撒布,9月中下旬收获。稻瘟病流行过程的特点是叶瘟发生得晚,发展也慢,到7月中旬拔节至孕穗期出现急性型病斑,8月上旬抽穗期才普遍发病。这样,叶瘟的上升便一直与穗瘟期连接起来。主要为害是穗瘟。本区稻瘟的流行也是以穗 相似文献
8.
多个水稻品种混合栽培控制稻瘟病示范效果显著 总被引：1，自引：0，他引：1
稻瘟病，尤其是穗颈瘟─直是武进市水稻生产上重点防治的病害。1993年以来的 8 a中有3 a(1996、1998、1999年 )穗颈瘟局部大流行，严重田块病穗率90％～100％，病指 80～90，虽经药剂防治，仍造成水稻产量的严重损失。水稻品种混合间栽，根据混合使用多种不同基因型水稻品种，使病菌各类群群体保持相对低的水平，优势类群不易形成，从而能达到降低发病程度的目的。为此笔者于2000年在礼加镇进行了水稻品种混合间栽控病试验示范。 试验有4个主栽品种，分别为9707、9520、9915和9325，间栽品种为苏御糯。 混合间栽试验区面积2 533 m2… 相似文献
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Lydia Bousset Claude de Vallavieille-Pope 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(1):13-24
Changes in pathotype frequencies due to sexual reproduction during summer were assessed in barley plots inoculated at the start of the growing season with powdery mildew isolates of the pathotype GL1 (Va22Vh) which belonged to a clonal lineage frequent in Northern France in 1992–1996 and was absent or rare in the local population at the time of the study. The capacity for recombination among isolates belonging to the pathotype GL1 was confirmed by performing crosses in the greenhouse. The field experiment was repeated over two years, with two field plots inoculated with either a single isolate (one mating type) or four isolates (two mating types). Following artificial inoculation, the frequency of GL1 increased to between 40% and 80% of the total conidia population at the end of the asexual epidemics before summer. When only one isolate (one mating type) of the pathotype GL1 was present, the frequency of the GL1 pathotype decreased to 4–5% of the ascospore population, following sexual recombination between the inoculated isolate and the local natural population. When isolates of both mating types of GL1 were inoculated, however, the GL1 pathotype remained dominant (28%) in the ascospore population. A pathotype dominant at the end of the summer might possibly have over-summered through asexual reproduction, or alternatively it may originate from sexual reproduction. The observed GL1 frequencies and numbers of virulences per isolate (complexity) observed on the field plots were compared to those calculated with a model assuming random or non-random mating. 相似文献
12.
Cohen Y 《Phytopathology》2002,92(3):300-307
ABSTRACT In this survey, 799 isolates of Phytophthora infestans collected from potato crops in Israel during 1983 to 2000 were analyzed for mating type and sensitivity to metalaxyl, and 324 were analyzed for race structure. The A(2) mating type, first recorded in 1983, fully dominated the pathogen population from 1983 until 1991 (9 years). It was thereafter replaced by the A(1) mating type, which dominated the population during 1993 to 2000. Metalaxyl-resistant isolates were first recorded in 1982. During 1983 to 1991, the majority of the isolates were resistant. Isolates with intermediate sensitivity (I) to this fungicide were first observed in 1993, when both A(1) and A(2) mating types occurred in the population. The proportion of I isolates gradually increased, reaching 39 to 41% in 1997 to 1998, and then declined to approximately 15% in 1999 to 2000. Pathogenicity to nine potato differential cultivars was determined for 80 potato isolates collected in 1983 to 1991, to 11 potato differentials in 173 isolates collected in 1993 to 1998, and in 71 potato isolates collected in 1999 to 2000. The first population was composed of 5 races with race 1,3,4,7,8,10 predominating (76%), the second population was composed of 19 races with race 1,3,4,7,8,10,11 predominating (63%), and the third population exhibited 42 (34 new) races with no single predominating race. RG-57 DNA fingerprinting and allozymes loci assays of 23 isolates revealed that isolates collected during 1984 to 1986 belonged to the PO-57 lineage, whereas those collected during 1997 to 1999 belonged to the RFO-39 lineage. Among isolates collected during 1993 to 1995, two unreported DNA fingerprinting patterns were found. Severe late blight epidemics occurred in tomato crops during 1998 to 2000. Of 35 tomato isolates, 28 were A(1) and only 7 were A(2). Of these tomato isolates, 94% were sensitive to metalaxyl. Almost every isolate had a different race structure on the 11 potato differentials. When inoculated onto three tomato differential cultivars, tomato isolates showed a virulence much more enhanced than potato isolates. The data suggest the Israeli population of P. infestans has passed through three major genetic changes during the past 18 years: in 1983, 1993, and 1999. The recent change included host specialization to tomato. 相似文献
13.
Low pathotype diversity in a recombinant Puccinia striiformis population through convergent selection at the eastern Himalayan centre of diversity (Nepal) 
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下载免费PDF全文 S. Ali S. Sharma M. Leconte S. J. A. Shah E. Duveiller J. Enjalbert C. de Vallavieille‐Pope 《Plant pathology》2018,67(4):810-820
Worldwide Puccinia striiformis f. sp. tritici (Pst) epidemics have been reported to be driven by few genetic lineages, while a high diversity is evident at the Pst Himalayan centre of diversity. This study investigated the relationship between pathotype diversity and genetic structure in Nepal, the eastern Himalayan region, which has been largely unexplored. Despite the high genetic diversity and recombinant structure detected through microsatellite genotyping, characterization of virulence phenotypes for 62 isolates identified only eight pathotypes, with two pathotypes predominant over all the populations. This is in contrast to the Pakistani and Chinese recombinant populations, where high pathotype diversity is associated with genetic diversity. The most prevalent Nepali pathotype was not a unique clonal lineage, but was represented by seven multilocus genotypes from four distinct genetic subgroups, suggesting strong directional selection on virulence genes, resulting in convergent pathotypes in distinct genetic groups. This convergent selection is discussed in comparison with clonal French and recombinant Pakistani populations. Additionally, the Nepali Pst population carried virulence to 17 out of 24 tested yellow rust resistance genes (Yr), with the absence of virulence to Victo and Early Premium and resistance genes Yr5, Yr10, Yr15, Yr24 and Yr26. Virulence to Yr2, Yr7, Yr27 and YrSu were fixed in all isolates, in line with the deployment of these resistance genes in Nepal. The results reflect the influence of resistance gene deployment on selection of virulence and pathotypes in a recombinant pathogen population, which must be considered in the context of durable resistance gene deployment. 相似文献
14.
为明确云南省水稻细菌性条斑病菌(Xanthomonas oryzae pv. oryzicola, Xoc)的致病力分化以及不同类型水稻品种对Xoc的抗感特性,通过针刺接种法将云南省8个稻区采集的86株Xoc菌株,接种于6个携带不同抗性基因的水稻鉴别品种(IRBB4、IRBB5、IRBB14、IRBB18、IRBB21和IR24)。根据这些菌株在鉴别品种上的毒力差异进行了UPGMA聚类分析,将其划分为9个致病型(Ⅰ型 ~ Ⅸ 型)。其中,Ⅰ型为优势菌群,分布频率为50.5%。对不同稻区的优势菌群进行分析,发现云南省各稻区Xoc的致病型呈多样性分布,以强毒力的Ⅰ型为高频率致病型。选用 Ⅰ 型、Ⅱ 型和 Ⅵ 型代表菌株对云南省的80个主栽和区试水稻品种进行抗性评价,对3个致病型表现抗性的材料比例分别为30.0%、35.0%和57.5%。筛选出9个对3种致病型都表现为抗性的品种,其中“Deyou16”和“Changgui2”表现为高抗。研究结果可为云南省防治水稻细菌性条斑病的水稻区域性布局和抗性品种的利用提供理论依据。 相似文献
15.
Variation of pathotypes and races and their correlations with clonal lineages in Verticillium dahliae 下载免费PDF全文
下载免费PDF全文 R. M. Jiménez‐Díaz C. Olivares‐García J. L. Trapero‐Casas M. M. Jiménez‐Gasco J. A. Navas‐Cortés B. B. Landa M. G. Milgroom 《Plant pathology》2017,66(4):651-666
Understanding pathogenic variation in plant pathogen populations is key for the development and use of host resistance for managing verticillium wilt diseases. A highly virulent defoliating (D) pathotype in Verticillium dahliae has previously been shown to occur only in one clonal lineage (lineage 1A). By contrast, no clear association has yet been shown for race 1 with clonal lineages. Race 1 carries the effector gene Ave1 and is avirulent on hosts that carry resistance gene Ve1 or its homologues. The hypothesis tested was that race 1 arose once in a single clonal lineage, which might be expected if V. dahliae acquired Ave1 by horizontal gene transfer from plants, as hypothesized previously. In a diverse sample of 195 V. dahliae isolates from nine clonal lineages, all race 1 isolates were present only in lineage 2A. Conversely, all lineage 2A isolates displayed the race 1 phenotype. Moreover, 900‐bp nucleotide sequences from Ave1 were identical among 27 lineage 2A isolates and identical to sequences from other V. dahliae race 1 isolates in GenBank. The finding of race 1 in a single clonal lineage, with identical Ave1 sequences, is consistent with the hypothesis that race 1 arose once in V. dahliae. Molecular markers and virulence assays also confirmed the well‐established finding that the D pathotype is found only in lineage 1A. Pathogenicity assays indicated that cotton and olive isolates of the D pathotype (lineage 1A) were highly virulent on cotton and olive, but had low virulence on tomato. 相似文献
16.
Characterisation of the European pathogen population of Magnaporthe grisea by DNA fingerprinting and pathotype analysis 总被引：3，自引：0，他引：3
E. Roumen M. Levy J.L. Notteghem 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(4):363-371
The genetic variability among 41 isolates of the blast pathogen (Magnaporthe grisea) from five European rice growing countries was studied. The genealogy of the isolates was investigated by DNA fingerprinting and the results compared to the degree of similarity for (a)virulence factors. Fingerprinting grouped the isolates into five discrete lineages, that typically showed less than 65% band similarity. Within each lineage, two or more haplotypes were detected with a band similarity of 80% or higher. Each lineage showed a characteristic virulence pattern. All isolates of lineage E5 belonged to the same pathotype. The other lineages were composed of clusters of closely related pathotypes that showed variation for virulence to cultivars with certain known resistance genes, while remaining invariably (a)virulent to others. In most cases, lineage classification of an isolate could be easily inferred by its pathotype. Certain resistance genes and certain lineage-excluding resistance gene combinations appear to provide protection against all of the virulence factors sampled. 相似文献
17.
Ludwik S. Sujkowski Stephen B. Goodwin William E. Fry 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(6):555-561
Ninety-five isolates ofPhytophthora infestans collected throughout Poland during 1985–1991 and characterized for multilocus genotypes based on mating type, allozymes and DNA fingerprint, were analyzed for specific virulence to differential potato cultivars carrying ten major resistance genes. The multilocus analysis led to three groupings. The first group contained 22 isolates of a clonal lineage (PO-1) that is postulated to have been present in Europe during most of the twentieth century, but PO-1 isolates were recovered in Poland only during 1985–1988. This group contained, on average, virulence to 5.5 specific resistance genes per isolate. The second group consisted of 30 isolates in a clonal lineage (PO-4) that had not been detected before 1988. PO-4 isolates had virulence to a mean of 6.5 resistance genes per isolate. The third group was composed of 43 isolates representing 38 multilocus genotypes also not detected before 1988. These diverse genotypes had virulence to an average of 6.7 specific resistance genes per isolate. More than half (53%) of the PO-4 isolates shared a single pathotype. The group of 43 isolates was dominated by two pathotypes: the most common one (47% of the isolates) was the same pathotype that dominated PO-4 isolates; the next most common one (21%) differed from the most common one by the absence of virulence to resistance gene R5. The recent immigrant isolates (not detected before 1988) generally had virulence to a greater number of specific resistance genes than did isolates in the previous population [detected before 1988 (PO-1)]. Recent immigrant populations were dominated by one or two pathotypes, so their pathotypic diversity values were somewhat less than that of the previous population. 相似文献
18.
SALAMIAH Hajime AKAMATSU Yukitaka FUKUMASA-NAKAI Hiroshi OTANI Motoichiro KODAMA 《Journal of General Plant Pathology》2001,67(2):97-105
The genetic controls of host-specific toxin (HST) biosynthesis and the pathogenicity of A. alternata pathogens have been limited by the asexual nature of the life cycle of these fungi. We used a protoplast fusion system for
A. alternata to analyze the genetics of HST production and its relation to the specific pathogenicity of these pathogens. Drug-resistant
transformants were isolated by genetic transformation, using vectors conferring resistance to hygromycin B and geneticin,
for the A. alternata apple pathotype (AM-toxin producer) and A. alternata tomato pathotype (AAL-toxin producer), respectively. Protoplasts of the respective transformants were fused by electrofusion.
The majority of resultant stable fusants produced both AM- and AAL-toxins and were pathogenic to susceptible cultivars of
both apple and tomato. Pulsed-field gel electrophoresis analysis demonstrated that these fusants (or hybrids) carried small
1.7-and 1.1-Mb chromosomes, characteristic of the parental strains of the apple and tomato pathotypes, respectively. Detection
of the AMT gene, involved in AM-toxin biosynthesis, by polymerase chain reaction revealed that all fusants pathogenic to apple maintained
this gene. Microfluorimetry analysis using propidium iodide staining suggested that the fusants might be diploid.
Received 14 November 2000/ Accepted in revised form 11 December 2000 相似文献
19.
Verticillium dahliae isolates from potato on the island of Hokkaido (potato isolates) and those belonging to pathotypes A (eggplant pathotype),
B (tomato pathotype) and C (sweet pepper pathotype) were divided into three distinct groups by RAPD and REP-PCR. The three
DNA groups I, II, III consisted of pathotypes A and C, pathotype B and potato isolates, respectively. The potato isolates
were assigned to pathotype A on the basis of pathogenicity. Another set of potato isolates was further collected from eight
potato cropping regions on Hokkaido to further examine the relationships among them in detail. Only one of these isolates
was identified as DNA group II, but all the others were classified as DNA group III. Isolates from daikon, eggplant, and melon
on Hokkaido also belonged to DNA group III. These results suggest that V. dahliae isolates from Hokkaido are unique at the DNA level and different from other pathotype A isolates in Japan.
Received 28 February 2000/ Accepted in revised form 6 November 2000 相似文献