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1.
J. C. Dorst 《Euphytica》1960,9(3):265-271
In the course of ages and under widely different conditions nature, through mutation, spontaneous crossing and natural selection, has presented mankind with a great wealth of material.After mentioning the source of resistance for many cases the writer has grouped them into the catagories existing varieties, land races and gene centres.In former years taxonomists searched for new species to collect them for herbariums, nowadays living collections are planted. Plant breeders now are hunting for new valuable genes.
Lecture read at the A-course Resistance in agriculture, 12–14 Jan. 1959, organised by the Royal Society of Agricultural Science and the Netherlands Society of Graduates in Agriculture at Wageningen. 相似文献
Lecture read at the A-course Resistance in agriculture, 12–14 Jan. 1959, organised by the Royal Society of Agricultural Science and the Netherlands Society of Graduates in Agriculture at Wageningen. 相似文献
2.
Pim Lindhout 《Euphytica》2002,124(2):217-226
Polygenic resistance is generally quantitative without clear race specific effects. With the onset of molecular markers technologies,
the identification of chromosome regions that are involved in quantitative resistance has become feasible. These regions are
designated quantitative trait loci (QTLs). The mapping of `major' QTLs can be independent of environment, season, year or
race of the challenging pathogen. However, the detection of minor QTLs may be dependent on the `environment'. As QTLs are
defined by the position on the genome and the quantitative effect on resistance, they are not informative about the mechanism
of resistance. By comparing QTL with the loci that are involved in race specific resistance the coincidence of these loci
may suggest a common mechanism. However, the histological characterisation of the resistance is more informative about the
resistance mechanism. Estimations about the durability of polygenic, quantitative resistance are still academic as there is
hardly any experience with large-scale usage of quantitative resistance over a longer period. The clearest example of non-durable
resistance is race specific monogenic resistance that is associated with a hypersensitive response (HR). Hence, there is a
great chance that polygenic resistance that is not associated with HR is more durable. In some pathosystems with a long experience
with non-durable race specific HR genes, quantitative resistance offers a good alternative and marker-assisted breeding will
facilitate the exploitation of these resistance for commercial purposes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
J. Helms Jørgensen 《Euphytica》1977,26(1):55-62
Summary Ten barley mutants and five Ethiopian barley lines representing 11 independently arisen powdery mildew resistance genes in the ml-o locus were tested at the seedling stage to cultures of the powdery mildew fungus from Europe, Israel, USA. Canada, and Japan. They were resistant with infection type 0/(4) in all tests. They were also resistant to field populations of the pathogen when scored in disease nurseries at more than 78 locations in 29 countries in Europe, the Near East, North and South America. New Zealand, and Japan. This indicates that the 11 genes confer the same, world-wide spectrum of powdery mildew resistance. They have no effect on several other barley diseases such as stripe rust and leaf rust.Part of the research reported here was carried out under IAEA Research Agreement No 1043 and Research Contract No 139-74-1 BIO DK with the European Atomic Energy Community. 相似文献
4.
Summary By using 15 available mono/nullisomic lines of Sun II back ground, the Heterodera avenae resistance gene in Nelson (from Avena sativa CI 3444) and Panema (from A. sterilis I. 376) were located on monosome XV. Genes with smaller effects were located on monosomes VIII and X. The absence of these genes derived from Sun II would increase cyst production on plants lacking major resistance genes. 相似文献
5.
Systemic acquired resistance 总被引：2，自引：0，他引：2
Plants can be induced to switch on defense reactions to a broad range of pathogens as a result of prior exposure to pathogens
or to various chemicals or physical stress. Induced resistance is expressed locally, at the site of the infection or systemically,
at sites remotely located from the initial infection. Upon recognition of the initial stimulus by the plant, a signal transduction
pathway is set in motion, that includes intra and intercellular signals, and results in the activation of defense mechanisms,
mostly by expression of new genes. This brief review will focus on some of the recent advances in the understanding of systemic
acquired resistance and on the role played by salicylic acid in this process.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
6.
Host-plant resistance is the best means to control the key disease of lentil-vascular wilt, caused by Fusarium oxysporum Schlecht.
emend. Snyder & Hansen f.sp. lentis Vasudeva and Srinivasan. Systematic screening for resistance to lentil wilt was initiated
in the field in 1993, in a wilt-sick plot in North Syria, with a core collection of 577 germplasm accessions from 33 countries.
A subset (88 accessions) of mostly resistant accessions was re-screened in 1994. The most resistant accessions came from Chile,
Egypt, India, Iran and Romania. Variation among accessions in the temporal pattern of wilting was analyzed. The limited wilting
in resistant accessions followed a linear model through time, whereas the pattern for susceptible accessions was better described
with an exponential model. This temporal variation emphasizes the need for repeated scoring during screening for resistance
to lentil vascular wilt to identify ‘late-wilters’. To overcome spatial variation in inoculum density, the efficacy of using
wilt scores from a systematically-repeated susceptible control in covariate analysis was tested. Covariance analysis significantly
improved overall screening by 3% in 1993, but the improvement was non-significant in 1994. The results emphasize the relative
uniformity of disease pressure in the wilt-sick plot and suggest that covariance analysis of a systematically arranged control
will be of greater benefit in land which is less uniformly infected.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Summary Seedling and flag leaves of three barley cultivars were simultaneously inoculated with urediospores of barley leaf rust, race 1-2-1, and incubated at the same greenhouse bench. The inoculated leaves were harvested before urediospore formation was initiated. The volume of a large number of colonies was estimated by measuring colony area and colony depth by embedding the colony containing leaf segments into paraffin for microtome cutting. The colony volume was considerably smaller in flag leaves than in seedling leaves even in the extremely susceptible cultivar. On average the difference was about tenfold. 相似文献
8.
Localization of a resistance gene and identification of sources of resistance to barley leaf stripe 总被引：2，自引：0，他引：2
In order to determine more precisely the location of the barley leaf stripe gene, called the ‘Vada-resistance gene’, on barley chromosome 2, 63 chromosome-doubled barley lines were tested. Using data on known chromosome 2 genetic markers, the ‘Vada-resistance gene’ was estimated to be located between the markers MSU21 and Xris45b, and at a distance of about 20% recombination from the powdery mildew resistance gene MILa. We suggest that the ‘Vada-resistance gene’ is designated Rdg1a and that all former leaf stripe resistance gene designations should be rejected. To identify possible new sources of resistance, 11 barley cultivars/lines known to possess leaf stripe resistance and originating from different parts of the world, were tested with one Danish and two Syrian isolates of the leaf stripe fungus. Three apparently genetically different sources of race-specific resistance were found. The ‘Vada-resistance’ in the cultivar ‘Golf was effective against seven out of eight isolates’ populations of the leaf stripe fungus differing in geographical origin. 相似文献
9.
Chickpea wilt caused by Fusarium oxysporum f. sp. ciceris is one of the major yield limiting factors in chickpea. The disease causes 10–90% yield losses annually in chickpea. Eight
physiological races of the pathogen (0, 1A, 1B/C, 2, 3, 4, 5 and 6) are reported so far whereas additional races are suspected
from India. The distribution pattern of these races in different parts of the world indicates regional specificity for their
occurrence leading to the perception that F. oxysporum f. sp. ciceris evolved independently in different regions. Pathogen isolates also exhibit differences in disease symptoms. Races 0 and 1B/C
cause yellowing syndrome whereas 1A, 2, 3, 4, 5 and 6 lead to wilting syndrome. Genetics of resistance to two races (1B/C
and 6) is yet to be determined, however, for other races resistance is governed either by monogenes or oligogenes. The individual
genes of oligogenic resistance mechanism delay onset of disease symptoms, a phenomenon called as late wilting. Slow wilting,
i.e., slow development of disease after onset of disease symptoms also occurs in reaction to pathogen; however, its genetics
are not known. Mapping of wilt resistance genes in chickpea is difficult because of minimal polymorphism; however, it has
been facilitated to great extent by the development of sequence tagged microsatellite site (STMS) markers that have revealed
significant interspecific and intraspecific polymorphism. Markers linked to six genes governing resistance to six races (0,
1A, 2, 3, 4 and 5) of the pathogen have been identified and their position on chickpea linkage maps elucidated. These genes
lie in two separate clusters on two different chickpea linkage groups. While the gene for resistance to race 0 is situated
on LG 5 of Winter et al. (Theoretical and Applied Genetics 101:1155–1163, 2000) those governing resistance to races 1A, 2, 3, 4 and 5 spanned a region of 8.2 cM on LG 2. The cluster of five resistance
genes was further subdivided into two sub clusters of 2.8 cM and 2.0 cM, respectively. Map-based cloning can be used to isolate
the six genes mapped so far; however, the region containing these genes needs additional markers to facilitate their isolation.
Cloning of wilt resistance genes is desirable to study their evolution, mechanisms of resistance and their exploitation in
wilt resistance breeding and wilt management. 相似文献
10.
大麦种质资源成株期抗旱性鉴定及抗旱指标筛选 总被引：6，自引：0，他引：6
Yin-Ping XU Yong-Dong PAN Qiang-De LIU Yuan-Hu YAO Yan-Chun JIA Cheng REN Ke-Cang HUO Wen-Qing CHEN Feng ZHAO Qi-Jun BAO Hua-Yu ZHANG 《作物学报》2020,46(3):448-461
干旱是影响大麦生产的主要因素之一。在鉴定大麦种质资源成株期抗旱性的基础上,筛选抗旱指标,可为培育抗旱品种提供依据。本研究在2016和2017年在大麦生长主要需水期平均降雨量不足40 mm的甘肃省武威市进行田间试验,以30份大麦种质资源为研究对象,设置正常灌水和干旱胁迫处理,测定大麦株高、穗长、分蘖数、单株粒数、单株粒重、穗粒数、千粒重和产量,采用抗旱性度量值(D)、综合抗旱系数(CDC)、加权抗旱系数(WDC)、相关分析、频次分析、主成分分析、灰色关联度分析、隶属函数分析、聚类分析和逐步回归分析相结合的办法,对其进行抗旱性鉴定及抗旱指标的筛选。干旱胁迫对测定的各指标均有极显著影响。频次分析表明,各指标对干旱胁迫反应的敏感程度依次为产量、株高、单株粒重、穗长、单株粒数、分蘖数、穗粒数和千粒重。相关分析表明,产量与株高、穗长、分蘖数、单株粒数和单株粒重呈极显著正相关,与穗粒数呈显著正相关、与千粒重呈不显著正相关。主成分分析表明,5个主成分可以代表大麦抗旱性86.39%的原始数据信息量。基于D值、CDC值和WDC值的大麦种质资源抗旱性排序基本一致。灰色关联度分析表明,各指标单项抗旱系数值与D值间的关联度依次为产量、单株粒重、单株粒数、穗长、株高、分蘖、穗粒数和千粒重,各指标DC值与WDC值间的关联大小依次为单株粒重、产量、单株粒数、分蘖、穗长、穗粒数、株高和千粒重。根据D值进行聚类分析,将供试大麦种质资源依据抗旱性从强到弱分为5个抗旱等级,其中1级5份、2级1份、3级11份、4级10份、5级3份。除分蘖和千粒重外,其余指标的隶属函数值、CDC值、D值和WDC值均随着抗旱级别的升高而增大。回归分析表明, 5个测定指标均与D值密切相关。干旱胁迫对大麦种质资源成株期各指标均有极显著影响。确定了D值为适宜的抗旱鉴定指标。筛选出成株期抗旱性强的大麦种质资源甘啤7号、Z06-278-9、MERIT、NEVADA和西藏25,可为大麦抗旱育种、抗旱机制以及干旱调控缓解机制的研究提供技术支持。穗长、单株粒数、单株粒重、穗粒数、产量可作为大麦种质资源成株期简单、直观的抗旱评价指标。 相似文献
11.
Giovani Greigh de Brito Eveline Teixeira Caixeta Ana Paula Gallina Eunize Maciel Zambolim Laércio Zambolim Valdir Diola Marcelo Elhers Loureiro 《Euphytica》2010,173(2):255-264
The most important disease of Coffea arabica is coffee leaf rust caused by the fungus Hemileia vastatrix. The purpose of this study was to characterize the inheritance of coffee resistance gene(s) to race II of this pathogen and
to identify and map molecular markers linked to this trait. Different populations were used: F2 (160 plants), BCr (20), and BCs (135), derived from a cross between the resistant genotype Híbrido de Timor UFV 427-15 and
the susceptible cultivar Catuaí Amarelo UFV 2143-236 (IAC 30). The segregation analysis showed that the resistance of Híbrido
de Timor to race II of the H. vastatrix is conferred by a single dominant gene. The amplification of 176 AFLP (Amplified fragment length polymorphism) primer combinations
using bulked segregant analysis (BSA) allowed the identification of three molecular markers linked to the resistance gene.
Genetic mapping of these three markers in the F2 population indicated that they are distributed on both sides, flanking the resistance gene. The markers E.CTC/M.TTT405 and
E.CGT/M.TGT300 were found linked to the resistance gene at 8.69 cM (LOD 18.91) and 25.10 cM (LOD 5.37), respectively, while
E.CCT/M.TTC230 was localized on the other side of the gene, at 20.50 cM (LOD 6.15). These markers are the first rust resistance
markers identified in Híbrido de Timor and can be useful for marker assisted selection in coffee breeding programs. 相似文献
12.
Twenty-one bread-wheat entries were selected after careful screening for complete or near-complete resistance to yellow rust (Puccinia striiformis), stem rust (P. graminis), and leaf rust (P. recondita). In 1987, the 21 entries were intercrossed in a near-half diallel scheme. The resulting 190 F2 populations were advanced to F7 under selection for complete resistance to the three rusts and for good agronomic types. In 1992 the 21 parents and 140 selected F7 lines were assessed for their resistance to the three rusts. Of the 21 parents, 12 showed a breakdown of yellow rust resistance, five a breakdown of stem rust resistance and two a breakdown of leaf rust resistance. In addition, several of the 140 selected F7 lines, all still resistant in F6, had become susceptible to one or more of the rusts. It appears that a progression towards more complex races, especially of yellow rust, is inevitable for the wheat-cereal rust patho-systems when the selection is for complete or near-complete resistance. 相似文献
13.
Mapping of QTL for resistance to powdery mildew and resistance gene analogues in perennial ryegrass 总被引：1，自引：0，他引：1
The objective of this study was to map resistance gene analogues (RGA) and quantitative trait loci (QTL) for powdery mildew resistance in perennial ryegrass ( Lolium perenne L.). The mapping population consisted of 184 F2 genotypes produced from a cross between one genotype of a synthetic perennial ryegrass variety Veyo and one genotype from the perennial ryegrass ecotype Falster. The greenhouse infection was measured as number of sporulating colonies on a 10-cm leaf area with the maximum possible number of colonies to be counted set to 50. The range of infection scores in the population was 0–50 and the heritability was 71.7%. In total, two QTL for powdery mildew resistance were identified, and mapped to linkage groups (LG) LG3 and LG7. Individually, these QTL explained between 7.5% and 22.1% of the total phenotypic variation. Six RGA and three laccases were mapped to LG2, LG3, LG4, LG5 and LG7, however, no close linkage between RGA and QTL was observed. 相似文献
14.
15.
摘要：针对我国玉米种质遗传基础狭窄,缺少优良抗性种质资源的问题,利用外引温热带玉米种质改良国内种质的方法,即鉴定并发掘外引玉米种质的优良抗病、抗逆基因,通过与国内骨干系杂交或组建抗病、抗逆群体后,鉴别筛选出含抗病、抗逆基因的材料回交纯合,最终选育出新的自交系用于我国杂交种的培育,从而提高国内玉米的抗病性和抗逆性,并利用外来种质的优良抗逆基因选育出特早熟玉米新品种植9831。 相似文献
16.
The greenbug [Schizaphis graminum (Rondani)] is an extremely damaging pest of barley (Hordeum vulgare L.), particularly in the southern Great Plains of the USA. Winter barley targeted for production in this region should incorporate resistance to greenbug in the form of the resistance gene Rsg1a (in ‘Post 90′) or Rsg2b (in PI 426756). This study was conducted to fully characterize the resistance profile of these two genes against important greenbug biotypes, and to determine which of the two resistance genes is most effective in protecting barley from the greenbug. Eight barley and four wheat cultivars and germplasms were challenged with six greenbug biotypes and damage ratings were recorded for each combination. In five of the six tests, ‘Post 90’ was significantly more resistant than PI 426756 to greenbug feeding damage. Based on the results presented here, we conclude that the resistance gene, Rsg1a, in ‘Post 90’ is the better choice for use in breeding programmes and will provide better protection than Rsg2b against the greenbug. 相似文献
17.
Four components of resistance to Uromyces viciae-fabae, namely, latent period (LP), infection efficiency (IE), pustule size (PS) and spore production (SP) were evaluated on lentil (Lens culinaris) in glasshouse experiments. Four cultivars, Gudo, R-186, FLIP-87-66L and FLIP-89-60L, with different levels of resistance, and the susceptible check EL-142, were included in this study. The cultivars were also compared for area under the disease progress curve (AUDPC), area under the pustule density curve (APDC), apparent infection rate (rG), disease severity (DS), pustule density (PD), LP and PS under field conditions. Gudo and R-186 had significantly smaller and fewer pustules, lower spore yield and longer latent period than EL-142. FLIP-87-66L was intermediate for infection efficiency and pustule size. In addition, significant differences were found between cultivars for AUDPC, APDC, DS and rG. Estimates of AUDPC, APDC, DS and rG were reduced in Gudo, R-186 and FLIP-87-66L compared with the susceptible check EL-142. FLIP-89-60L also showed low AUDPC, APDC and DS. Some of the components obtained in the field were significantly correlated with each other (r = 0.92–0.99, P 0.05) and those measured in the glasshouse. Most of the components studied in the glasshouse were significantly (P 0.05) correlated with AUDPC and DS. Data indicated the existence of incomplete [partial (PR)] resistance in the test cultivars, and the possibility of using IE, LP, SP and PS as selection criteria in the evaluation of PR to rust in lentil. Since there was an interdependence of the components, selection based on more than one component should help obtain lines with higher levels of PR. The AUDPC, DS and rG could also be used for selecting lines with PR in the field. 相似文献
18.
19.
Anju Pathania P. N. Sharma O. P. Sharma R. K. Chahota Bilal Ahmad P. Sharma 《Euphytica》2006,149(1-2):97-103
Summary Forty nine common bean lines comprising of exotic accessions and locally grown cultivars evaluated against Colletotrichum lindemuthianum exhibited differential resistance to its races in Himachal Pradesh, a north-western Himalayan state of India. Some exotic accessions like G 2333, Cornell 49242, PI 207262, Mexique 222, TO, Perry Marrow, Kaboon and Widusa were resistant to more than five Indian races, whereas two Indian accessions KRC-5 and Hans showed resistance to six and four races, respectively. However, nine accessions KRC-8, KR-40, KR-43, KR-81, KR-62-2, KR-90, KR-142, KR-148, and KR-216 were resistant to three races. Race specific resistance has been observed in different bean cultivars. Studies on inheritance of resistance in exotic accession G 2333 and Indian accession, KRC-5 showed that two independent dominant genes conferred resistance in G 2333 to race 3 and 515 and a single dominant gene controlled resistance in KRC-5 to race 775, indicating resistance from these sources is easily transferable to the locally adapted susceptible cultivars. 相似文献
20.
A total of 4,681 accessions of Hordeum vulgare landrace material from Ethiopia, East Mediterranean, Near East, Nepal and China
were sown in the field and subjected to the natural powdery mildew epidemic in Denmark. Apparently resistant accessions were
selected. Selfed progeny from them were retested and reselected in subsequent years at four locations in Denmark. Finally,
16 promising donors of resistance were retained. They were characterized in the field and tested in the seedling stage for
reaction to up to 72 different isolates of the powdery mildew fungus. The absence of the corresponding virulences in the Danish
airborne powdery mildew population was ascertained in five years. The resistances in the 16 donors are apparently mutually
different and from known sources of powdery mildew resistance in barley.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献