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1.
Costly resistance to parasitism: evidence from simultaneous quantitative trait loci mapping for resistance and fitness in Tribolium castaneum 下载免费PDF全文
Information on the molecular basis of resistance and the evolution of resistance is crucial to an understanding of the appearance, spread, and distribution of resistance genes and of the mechanisms of host adaptation in natural populations. One potential important genetic constraint for the evolution of resistance is fitness cost associated with resistance. To determine whether host resistance to parasite infection is associated with fitness costs, we conducted simultaneous quantitative trait loci (QTL) mapping of resistance to parasite infection and fitness traits using the red flour beetle (Tribolium castaneum) and the tapeworm parasite (Hymenolepis diminuta) system in two independent segregating populations. A genome-wide QTL scan using amplified fragment length polymorphism (AFLP) markers revealed three QTL for beetle resistance to tapeworm infection. These three QTL account for 44-58% variance in beetle infection intensity. We identified five QTL for fecundity and five QTL for egg-to-adult viability, which accounted for 36-57% and 36-49%, respectively, of the phenotypic variance in fecundity and egg-to-adult viability. The three QTL conferring resistance were colocalized with the QTL affecting beetle fitness. The genome regions that contain the QTL for parasite resistance explained the majority of the variance in fecundity and egg-to-adult viability in the mapping populations. Colocalization of QTL conferring resistance to parasite infection and beetle fitness may result from the pleiotropic effects of the resistance genes on host fitness or from tight linkages between resistance genes and adverse deleterious mutations. Therefore, our results provide evidence that the genome regions conferring resistance to tapeworm infection are partially responsible for fitness costs in the resistant beetle populations. 相似文献
2.
Candidate defense genes from rice,barley, and maize and their association with qualitative and quantitative resistance in rice 总被引:23,自引:0,他引:23
Ramalingam J Vera Cruz CM Kukreja K Chittoor JM Wu JL Lee SW Baraoidan M George ML Cohen MB Hulbert SH Leach JE Leung H 《Molecular plant-microbe interactions : MPMI》2003,16(1):14-24
3.
Saal B Struss D 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(2):281-290
An introgression derived from the B genome of Brassica juncea in spring-type oilseed rape (B. napus) conferring recessively inherited cotyledon resistance against several pathotypes of the blackleg fungus Leptosphaeria maculans was mapped using PCR-based molecular markers. Resistance-associated B-genome-specific randomly amplified (RAPD) and resistance gene analog (RGA) DNA polymorphisms were converted into three sequence-specific markers (SCARs; B5-1520, C5-1000, RGALm). The flanking sequence of the RGALm locus was determined by genomic walking, leading to a 1,610-bp EcoRV fragment which showed extensive homology to known and putative resistance genes of a cluster on Arabidopsis chromosome 5. Partial sequence analysis of the genomic RAPD segment OPC-05-1700 revealed strong homology to the gibberellin 2-oxidase gene of Arabidopsis. The SCAR markers were analyzed in two segregating populations and were found to be linked in coupling to each other, and in repulsion to the resistance locus. In both populations, markers deviated significantly from a monogenic 3:1 segregation ratio, with plants lacking the markers being more frequent than expected. Although the mode of introgression is yet unknown, the recombinant individuals observed among susceptible progeny suggest homeology between the B-genome-specific segment and its B. napus counterpart. This would offer prospects for reducing the size of the introgression and further fine mapping of the resistance locus. 相似文献
4.
Genetic characterization of QTL associated with resistance to Fusarium head blight in a doubled-haploid spring wheat population. 总被引:12,自引:0,他引:12
Fusarium head blight (FHB) is one of the most important fungal wheat diseases worldwide. Understanding the genetics of FHB resistance is the key to facilitating the introgression of different FHB resistance genes into adapted wheat. The objectives of the present study were to detect and map quantitative trait loci (QTL) associated with FHB resistance genes and characterize the genetic components of the QTL in a doubled-haploid (DH) spring wheat population using both single-locus and two-locus analysis. A mapping population, consisting of 174 DH lines from the cross between DH181 (resistant) and AC Foremost (susceptible), was evaluated for type I resistance to initial infection during a 2-year period in spray-inoculated field trials, for Type II resistance to fungal spread within the spike in 3 greenhouse experiments using single-floret inoculation, and for resistance to kernel infection in a 2001 field trial. One-locus QTL analysis revealed 7 QTL for type I resistance on chromosome arms 2DS, 3AS, 3BS, 3BC (centromeric), 4DL, 5AS, and 6BS, 4 QTL for type II resistance on chromosomes 2DS, 3BS, 6BS, and 7BL, and 6 QTL for resistance to kernel infection on chromosomes 1DL, 2DS, 3BS, 3BC, 4DL, and 6BS. Two-locus QTL analysis detected 8 QTL with main effects and 4 additive by additive epistatic interactions for FHB resistance and identified novel FHB resistance genes for the first time on chromosomes 1DL, 4AL, and 4DL. Neither significant QTL by environment interactions nor epistatic QTL by environment interactions were found for either type I or type II resistance. The additive effects of QTL explained most of the phenotypic variance for FHB resistance. Marker-assisted selection for the favored alleles at multiple genomic regions appears to be a promising tool to accelerate the introgression and pyramiding of different FHB resistance genes into adapted wheat genetic backgrounds. 相似文献
5.
Blair MW Iriarte G Beebe S 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,112(6):1149-1163
Advanced backcross QTL analysis was used to identify quantitative trait loci (QTL) for agronomic performance in a population
of BC2F3:5 introgression lines created from the cross of a Colombian large red-seeded commercial cultivar, ICA Cerinza, and a wild common
bean accession, G24404. A total of 157 lines were evaluated for phenological traits, plant architecture, seed weight, yield
and yield components in replicated trials in three environments in Colombia and genotyped with microsatellite, SCAR, and phaseolin
markers that were used to create a genetic map that covered all 11 linkage groups of the common bean genome with markers spaced
at an average distance of every 10.4 cM. Segregation distortion was most significant in regions orthologous for a seed coat
color locus (R-C) on linkage group b08 and two domestication syndrome genes, one on linkage group b01 at the determinacy (fin) locus and the other on linkage group b02 at the seed-shattering (st) locus. Composite interval mapping analysis identified a total of 41 significant QTL for the eight traits measured of which
five for seed weight, two for days to flowering, and one for yield were consistent across two or more environments. QTL were
located on every linkage group with b06 showing the greatest number of independent loci. A total of 13 QTL for plant height,
yield and yield components along with a single QTL for seed size showed positive alleles from the wild parent while the remaining
QTL showed positive alleles from the cultivated parent. Some QTL co-localized with regions that had previously been described
to be important for these traits. Compensation was observed between greater pod and seed production and smaller seed size
and may have resulted from QTL for these traits being linked or pleiotropic. Although wild beans have been used before to
transfer biotic stress resistance traits, this study is the first to attempt to simultaneously obtain a higher yield potential
from wild beans and to analyze this trait with single-copy markers. The wild accession was notable for being from a unique
center of diversity and for contributing positive alleles for yield and other traits to the introgression lines showing the
potential that advanced backcrossing has in common bean improvement. 相似文献
6.
Muhammad A. Mulki Abdulqader Jighly Gouyou Ye Livinus C. Emebiri David Moody Omid Ansari Francis C. Ogbonnaya 《Molecular breeding : new strategies in plant improvement》2013,31(2):299-311
Soilborne pathogens such as cereal cyst nematode (CCN; Heterodera avenae) and root lesion nematode (Pratylenchus neglectus; PN) cause substantial yield losses in the major cereal-growing regions of the world. Incorporating resistance into wheat cultivars and breeding lines is considered the most cost-effective control measure for reducing nematode populations. To identify loci with molecular markers linked to genes conferring resistance to these pathogens, we employed a genome-wide association approach in which 332 synthetic hexaploid wheat lines previously screened for resistance to CCN and PN were genotyped with 660 Diversity Arrays Technology (DArT) markers. Two sequence-tagged site markers reportedly linked to genes known to confer resistance to CCN were also included in the analysis. Using the mixed linear model corrected for population structure and familial relatedness (Q+K matrices), we were able to confirm previously reported quantitative trait loci (QTL) for resistance to CCN and PN in bi-parental crosses. In addition, we identified other significant markers located in chromosome regions where no CCN and PN resistance genes have been reported. Seventeen DArT marker loci were found to be significantly associated with CCN and twelve to PN resistance. The novel QTL on chromosomes 1D, 4D, 5B, 5D and 7D for resistance to CCN and 4A, 5B and 7B for resistance to PN are suggested to represent new sources of genes which could be deployed in further wheat improvement against these two important root diseases of wheat. 相似文献
7.
The resistance of rice to ozone (O3) is a quantitative trait controlled by nuclear genes. The identification of quantitative trait loci (QTL) and analysis of molecular markers of O3 resistance is important for increasing the resistance of rice to O3 stress. QTL associated with the O3 resistance of rice were mapped on chromosomes 1, 7 and 11 using 164 recombinant inbred (RI) lines from a cross between 'Milyang 23' and 'Gihobyeo'. The quantitative trait loci were tightly linked to the markers RG109, C507 and RG1094 and were detected in each of three replications. The association between these markers and O3 resistance in 26 rice cultivars and doubled haploid (DH) populations was analysed. The markers permit the screening of rice germplasm for O3 resistance and the introduction of resistance into elite lines in breeding programs. 相似文献
8.
Soil water-logging can cause severe damage to soybean [Glycine max (L.) Merr.] and results in significant yield reduction. The objective of this study was to identify quantitative trait loci
(QTL) that condition water-logging tolerance (WLT) in soybean. Two populations with 103 and 67 F6:11 recombinant inbred lines (RILs) from A5403 × Archer (Population 1) and P9641 × Archer (Population 2), respectively, were
used as the mapping populations. The populations were evaluated for WLT in manually flooded fields in 2001, 2002, and 2003.
Significant variation was observed for WLT among the lines in the two populations. No transgressive tolerant segregants were
observed in either population. Broad-sense heritability of WLT for populations 1 and 2 were 0.59 and 0.43, respectively. The
tolerant and sensitive RILs from each population were selected to create a tolerant bulk and a sensitive bulk, respectively.
The two bulks and the parents of each population were tested with 912 simple sequence repeat (SSR) markers to select candidate
regions on the linkage map that were associated with WLT. Markers from the candidate regions were used to genotype the RILs
in both populations. Both single marker analysis (SMA) and composite interval mapping (CIM) were used to identify QTL for
WLT. Seventeen markers in Population 1 and 15 markers in Population 2 were significantly (p <0.0001) associated with WLT in SMA. Many of these markers were linked to Rps genes or QTL conferring resistance to Phytophthora sojae Kaufmann and Gerdemann. Five markers, Satt599 on linkage group (LG) A1, Satt160, Satt269, and Satt252 on LG F, and Satt485
on LG N, were significant (p <0.0001) for WLT in both populations. With CIM, a WLT QTL was found close to the marker Satt385 on LG A1 in Population 1
in 2003. This QTL explained 10% of the phenotypic variation and the allele that increased WLT came from Archer. In Population
2 in 2002, a WLT QTL was located near the marker Satt269 on LG F. This QTL explained 16% of the phenotypic variation and the
allele that increased WLT also came from Archer. 相似文献
9.
Li-yu Shi Zhuan-fang Hao Jian-feng Weng Chuan-xiao Xie Chang-lin Liu De-gui Zhang Ming-shun Li Li Bai Xin-hai Li Shi-huang Zhang 《Molecular breeding : new strategies in plant improvement》2012,30(2):615-625
Maize rough dwarf disease (MRDD) is a worldwide viral disease and causes significant yield losses in maize (Zea mays L.) production. In this study, we mapped and characterized quantitative trait loci (QTL) conferring resistance to MRDD using 89 F8 recombinant inbred lines derived from a cross between X178 (resistant parent) and B73 (susceptible). The population was evaluated for MRDD resistance in Baoding, Hebei Province, China (a hot spot of MRDD incidence) under natural infection in 2008 and 2009 and artificial inoculation in 2010. Genotypic variances for disease severity index (DSI) were highly significant in the population. Heritability estimates for DSI evaluation were 0.472 and 0.467 in 2008 and 2009, respectively. The linkage map was constructed using 514 gene-derived single nucleotide polymorphisms (SNPs) and 72 simple sequence repeat markers, spanning a genetic distance of 1,059.72?cM with an average interval of 1.8?cM between adjacent markers. Multiple-QTL model mapping detected a major QTL for MRDD resistance on chromosome 8, explaining 24.6?C37.3% of the phenotypic variation across three environments. In 2010, an additional QTL was detected on chromosome 10, explaining 15.8% of the phenotypic variation. The major QTL on chromosome 8 and the SNP markers (SNP31, SNP548, and SNP284) co-located with the QTL peak have potential for further functional genomic analysis and use in molecular marker-assisted selection for MRDD resistance in maize. 相似文献
10.
Powdery mildew and scald can cause significant yield loss in barley. In order to identify new resistance genes for powdery
mildew and scald in barley, two barley doubled haploid (DH) populations were screened for adult plant resistance in the field
and glasshouse under natural infection. The mapping populations included 92 DH lines from the cross of TX9425 × Franklin and
177 DH lines from the cross of Yerong × Franklin. Two quantitative trait loci (QTL) for resistance to powdery mildew were
identified in the TX9425 × Franklin population. These QTL were mapped to chromosomes 7H and 5H, respectively. The phenotypic
variation explained by the two QTL detected in this population was 22 and 17%, respectively. Three significant QTL were identified
from the Yerong × Franklin population for the resistance to powdery mildew; the major one, detected on the short arm of chromosome
1H, explained 66% of phenotypic variation. The major QTL for scald resistance, identified from two different populations which
shared a common parent, Franklin, were mapped in the similar position on 3H. However, the Franklin allele provided resistance
to one population but susceptibility to the other population. The Yerong allele on 3H showed much better resistance to scald
than the Franklin allele, which has not been reported before. Using high-density maps for both populations, some markers which
were very close to the resistance genes were identified. Transgression beyond the parents in disease resistances of the DH
populations indicates that both small-effect QTLs and genetic background may also have significant contributions towards the
resistance. 相似文献
11.
Lewers K.S. Crane E.H. Bronson C.R. Schupp J.M. Keim P. Shoemaker R.C. 《Molecular breeding : new strategies in plant improvement》1999,5(1):33-42
The objective of this study was to map the gene(s) conferring resistance to brown stem rot in the soybean cultivar BSR 101. A population of 320 recombinant inbred lines (RIL) was derived from a cross of BSR 101 and PI 437.654. Seedlings of each RIL and parent were inoculated by injecting stems with a suspension of spores and mycelia of Phialophora gregata, incubated in a growth chamber at 17°C, and assessed for resistance by monitoring the development of foliar and stem symptoms. The population also was evaluated with 146 RFLPs, 760 AFLPs, and 4 probes for resistance gene analogs (RGAs). Regression analysis identified a significant association between resistance and several markers on Linkage Group J of the USDA-ARS molecular marker linkage map. Interval analysis with Mapmaker QTL identified a major peak between marker RGA2V-1 and AFLP marker AAGATG152M on Linkage Group J. A second peak, associated only with stem symptoms, was identified between the RFLP B122I-1 and RGA2V-1, also on Linkage Group J. When composite interval mapping with QTL Cartographer was used, two linked QTL were identified with both foliar and stem disease assessment methods: a major QTL between AFLP markers AAGATG152E and ACAAGT260, and a minor QTL between RGA3I-3 and RGA3I-2. These results demonstrate that composite interval mapping gives increased precision over interval mapping and is capable of distinguishing two linked QTL. The minor QTL associated with the cluster of RGA3I loci is of special interest because it is the first example of a disease resistance QTL associated with a resistance gene analog. 相似文献
12.
Quincke MC Peterson CJ Zemetra RS Hansen JL Chen J Riera-Lizarazu O Mundt CC 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(7):1339-1349
Cephalosporium stripe, caused by Cephalosporium gramineum, can cause severe loss of wheat (Triticum aestivum L.) yield and grain quality and can be an important factor limiting adoption of conservation tillage practices. Selecting for resistance to Cephalosporium stripe is problematic; however, as optimum conditions for disease do not occur annually under natural conditions, inoculum levels can be spatially heterogeneous, and little is known about the inheritance of resistance. A population of 268 recombinant inbred lines (RILs) derived from a cross between two wheat cultivars was characterized using field screening and molecular markers to investigate the inheritance of resistance to Cephalosporium stripe. Whiteheads (sterile heads caused by pathogen infection) were measured on each RIL in three field environments under artificially inoculated conditions. A linkage map for this population was created based on 204 SSR and DArT markers. A total of 36 linkage groups were resolved, representing portions of all chromosomes except for chromosome 1D, which lacked a sufficient number of polymorphic markers. Quantitative trait locus (QTL) analysis identified seven regions associated with resistance to Cephalosporium stripe, with approximately equal additive effects. Four QTL derived from the more susceptible parent (Brundage) and three came from the more resistant parent (Coda), but the cumulative, additive effect of QTL from Coda was greater than that of Brundage. Additivity of QTL effects was confirmed through regression analysis and demonstrates the advantage of accumulating multiple QTL alleles to achieve high levels of resistance. 相似文献
13.
QTL Mapping of Downy Mildew Resistance in an Introgression Line Derived from Interspecific Hybridization Between Cucumber and Cucumis hystrix 总被引:1,自引:0,他引:1
Downy mildew (DM), caused by Pseudoperonospora cubensis (Berk. & M.A. Curtis) Rostovzev, is a worldwide major disease of cucumbers (Cucumis sativus L.). By screening 10 introgression lines (ILs) derived from interspecific hybridization between cucumber and the wild Cucumis, C. hystrix, through a whole plant assay, one introgression line (IL52) was identified with high DM‐resistance. IL52 was further used as a resistant parent to make an F2 population with ‘changchunmici’ (susceptible parent). The F2 population (300 plants) was investigated for DM‐yellowing, DM‐necrosis and DM‐resistance in the adult stage. A genetic map spanning 642.5 cM with 104 markers was constructed and used for QTL analysis from the population. Three QTL regions were identified on chromosome 5 and chromosome 6. By interval mapping analysis, two QTLs for DM‐resistance were determined on chromosome 5 (DM_5.1 and DM_5.2), which explained 17.9% and 14.2% of the variation, respectively. QTLs for DM‐yellowing were in the same regions as DM‐resistance. For DM‐necrosis, by interval mapping analysis, one QTL was determined on chromosome 5 (Necr_5.1) that explained 18.3% of the variation and one on chromosome 6 (Necr_6.1) that explained 13.9% of the variation. Our results indicated that the identification of molecular markers linked to the QTLs could be further applied for marker‐assisted selection (MAS) of downy mildew resistance in cucumber. 相似文献
14.
Chaerani R Smulders MJ van der Linden CG Vosman B Stam P Voorrips RE 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(3):439-450
Alternaria solani (Ellis and Martin) Sorauer, the causal agent of early blight (EB) disease, infects aerial parts of tomato at both seedling
and adult plant stages. Resistant cultivars would facilitate a sustainable EB management. EB resistance is a quantitatively
expressed character, a fact that has hampered effective breeding. In order to identify and estimate the effect of genes conditioning
resistance to EB, a quantitative trait loci (QTL) mapping study was performed in F2 and F3 populations derived from the cross
between the susceptible Solanum lycopersicum (syn. Lycopersicon esculentum) cv. ‘Solentos’ and the resistant Solanum arcanum (syn. Lycopersicon peruvianum) LA2157 and genotyped with AFLP, microsatellite and SNP markers. Two evaluation criteria of resistance were used: measurements
of EB lesion growth on the F2 plants in glasshouse tests and visual ratings of EB severity on foliage of the F3 lines in a
field test. A total of six QTL regions were mapped on chromosomes 1, 2, 5–7, and 9 with LOD scores ranging from 3.4 to 17.5.
Three EB QTL also confer resistance to stem lesions in the field, which has not been reported before. All QTL displayed significant additive gene action; in some cases a dominance effect was found. Additive × additive epistatic
interactions were detected between one pair of QTL. For two QTL, the susceptible parent contributed resistance alleles to
both EB and stem lesion resistance. Three of the QTL showed an effect in all tests despite methodological and environmental
differences. 相似文献
15.
J. A. Anderson R. W. Stack S. Liu B. L. Waldron A. D. Fjeld C. Coyne B. Moreno-Sevilla J. Mitchell Fetch Q. J. Song P. B. Cregan R. C. Frohberg 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(8):1164-1168
Genetic resistance to Fusarium head blight (FHB), caused by Fusarium graminearum, is necessary to reduce the wheat grain yield and quality losses caused by this disease. Development of resistant cultivars
has been slowed by poorly adapted and incomplete resistance sources and confounding environmental effects that make screening
of germplasm difficult. DNA markers for FHB resistance QTLs have been identified and may be used to speed the introgression
of resistance genes into adapted germplasm. This study was conducted to identify and map additional DNA markers linked to
genes controlling FHB resistance in two spring wheat recombinant inbred populations, both segregating for genes from the widely
used resistance source ’Sumai 3’. The first population was from the cross of Sumai 3/Stoa in which we previously identified
five resistance QTLs. The second population was from the cross of ND2603 (Sumai 3/Wheaton) (resistant)/ Butte 86 (moderately
susceptible). Both populations were evaluated for reaction to inoculation with F. graminearum in two greenhouse experiments. A combination of 521 RFLP, AFLP, and SSR markers were mapped in the Sumai 3/Stoa population
and all DNA markers associated with resistance were screened on the ND2603/Butte 86 population. Two new QTL on chromosomes
3AL and 6AS wer found in the ND2603/Butte 86 population, and AFLP and SSR markers were identified that explained a greater
portion of the phenotypic variation compared to the previous RFLP markers. Both of the Sumai 3-derived QTL regions (on chromosomes
3BS, and 6BS) from the Sumai 3/Stoa population were associated with FHB resistance in the ND2603/Butte 86 population. Markers
in the 3BS QTL region (Qfhs.ndsu-3BS) alone explain 41.6 and 24.8% of the resistance to FHB in the Sumai 3/Stoa and ND2603/Butte 86 populations, respectively.
This region contains a major QTL for resistance to FHB and should be useful in marker-assisted selection.
Received: 17 August 2000 / Accepted: 16 October 2000 相似文献
16.
Shen X Van Becelaere G Kumar P Davis RF May OL Chee P 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,113(8):1539-1549
Root-knot nematodes Meloidogyne incognita (Kofoid and White) can cause severe yield loss in cotton (Gossypium hirsutum L.). The objectives of this study were to determine the inheritance and genomic location of genes conferring root-knot nematode resistance in M-120 RNR, a highly resistant G. hirsutum line with the Auburn 623 RNR source of resistance. Utilizing two interspecific F2 populations developed from the same M-120 RNR by Gossypium barbadense (cv. Pima S-6) cross, genome-wide scanning with RFLP markers revealed a marker on Chromosome 7 and two on Chromosome 11 showing significant association with the resistant phenotype. The association was confirmed using SSR markers with the detection of a minor and a major dominant QTL on Chromosome 7 and 11, respectively. Combined across the two populations, the major QTL on Chromosome 11 Mi-C11 had a LOD score of 19.21 (9.69 and 9.61 for Pop1 and Pop2, respectively) and accounted for 63.7% (52.6 and 65.56% for Pop1 and Pop2, respectively) of the total phenotypic variation. The minor QTL locus on Chromosome 7 Mi
1
-C07 had a LOD score of 3.48 and accounted for 7.7% of the total phenotypic variation in the combined dataset but was detected in only one population. The allele from the M-120 RNR parent contributed to increased resistance in the Mi-C11 locus, but surprisingly, the Pima S-6 allele contributed to increased resistance in the Mi-C07 locus. The M-120 RNR allele in the Mi-C11 locus, derived from the Auburn 623 RNR, is likely to have originated from the Clevewilt 6 cultivar. Results from this study indicated that the SSR marker CIR316 may replace the laborious greenhouse screening in breeding programs to identify genotypes resistant to M. incognita. 相似文献
17.
T. Toojinda L. H. Broers X. M. Chen P. M. Hayes A. Kleinhofs J. Korte D. Kudrna H. Leung R. F. Line W. Powell L. Ramsay H. Vivar R. Waugh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(4):580-589
Stripe rust, leaf rust, and Barley Yellow Dwarf Virus (BYDV) are important diseases of barley (Hordeum vulgare L). Using 94 doubled-haploid lines (DH) from the cross of Shyri x Galena, multiple disease phenotype datasets, and a 99-marker
linkage map, we determined the number, genome location, and effects of genes conferring resistance to these diseases. We also
mapped Resistance Gene Analog Polymorphism (RGAP) loci, based on degenerate motifs of cloned disease resistance genes, in
the same population. Leaf rust resistance was determined by a single gene on chromosome 1 (7H). QTLs on chromosomes 2 (2H),
3 (3H), 5 (1H), and 6 (6H) were the principal determinants of resistance to stripe rust. Two- locus QTL interactions were
significant determinants of resistance to this disease. Resistance to the MAV and PAV serotypes of BYDV was determined by
coincident QTLs on chromosomes 1 (7H), 4 (4H), and 5 (1H). QTL interactions were not significant for BYDV resistance. The
associations of molecular markers with qualitative and quantitative disease resistance loci will be a useful information for
marker-assisted selection.
Received: 2 February 1999 / Accepted: 30 December 1999 相似文献
18.
Rajeev K. Varshney Manish K. Pandey Pasupuleti Janila Shyam N. Nigam Harikishan Sudini M. V. C. Gowda Manda Sriswathi T. Radhakrishnan Surendra S. Manohar Patne Nagesh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(8):1771-1781
Key message
Successful introgression of a major QTL for rust resistance, through marker-assisted backcrossing, in three popular Indian peanut cultivars generated several promising introgression lines with enhanced rust resistance and higher yield.Abstract
Leaf rust, caused by Puccinia arachidis Speg, is one of the major devastating diseases in peanut (Arachis hypogaea L.). One QTL region on linkage group AhXV explaining upto 82.62 % phenotypic variation for rust resistance was validated and introgressed from cultivar ‘GPBD 4’ into three rust susceptible varieties (‘ICGV 91114’, ‘JL 24’ and ‘TAG 24’) through marker-assisted backcrossing (MABC). The MABC approach employed a total of four markers including one dominant (IPAHM103) and three co-dominant (GM2079, GM1536, GM2301) markers present in the QTL region. After 2–3 backcrosses and selfing, 200 introgression lines (ILs) were developed from all the three crosses. Field evaluation identified 81 ILs with improved rust resistance. Those ILs had significantly increased pod yields (56–96 %) in infested environments compared to the susceptible parents. Screening of selected 43 promising ILs with 13 markers present on linkage group AhXV showed introgression of the target QTL region from the resistant parent in 11 ILs. Multi-location field evaluation of these ILs should lead to the release of improved varieties. The linked markers may be used in improving rust resistance in peanut breeding programmes. 相似文献19.
Mapping of the QTL (quantitative trait locus) conferring partial resistance to leaf blast in rice cultivar Chubu 32 总被引:7,自引:0,他引:7
Zenbayashi K Ashizawa T Tani T Koizumi S 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,104(4):547-552
The rice cultivar Chubu 32 possesses a high level of partial resistance to leaf blast. The number and chromosomal location
of genes conferring this resistance were detected by restriction fragment length polymorphism (RFLP) linkage mapping and quantitative
trait locus (QTL) analysis. For the mapping, 149 F3 lines derived from the cross between rice cultivar Norin 29, with a low level of partial resistance, and Chubu 32 were used,
and their partial resistance to leaf blast was assessed in upland nurseries. A linkage map covering six chromosomes and consisting
of 36 RFLP markers was constructed. In the map, only one significant QTL (LOD>2.0) for partial resistance was detected on
chromosome 11. This QTL explained 45.6% of the phenotypic variation. The segregation ratio of the F3 lines was 3:1 for partial
resistance to susceptibility. These results suggest that the partial resistance in Chubu 32 is controlled by a major gene.
Received: 15 March 2001 / Accepted: 13 August 2001 相似文献
20.
Nagabhushan H. C. Lohithaswa Anand S. Pandravada 《Molecular breeding : new strategies in plant improvement》2017,37(1):2
Sorghum downy mildew (SDM), caused by obligate biotrophic fungi Peronosclerospora sorghi, is an economically important disease of maize. The genetics of resistance was reported to be polygenic thereby necessitating identification of QTLs for resistance to SDM to initiate effective marker-assisted selection programs. During post-rainy and winter season of 2012, 645 F2:3 progeny families from the cross CML153 (susceptible) × CML226 (resistant) were screened for their reaction to SDM. Characterization of QTLs affecting resistance to SDM was undertaken using the genetic linkage map with 319 polymorphic SSR and SNP marker loci and the phenotypic data of F2:3 families. Three QTLs conferring resistance to SDM were consistently identified on chromosomes 2, 3 and 6 in both seasons. The resistant parent CML226 contributed all the QTL alleles conferring resistance to SDM. The major QTL located on chromosome 2 explained 38.68% of total phenotypic variation in the combined analysis with a LOD score of 9.12. All the three QTL showed partially dominant gene effects in combined analysis. The detection of more than one QTL supports the hypothesis that quantitative genes control resistance to P. sorghi. The generation was advanced to F6 using markers linked to major QTLs on chromosomes 2 and 3 to derive 33 SDM resistant maize inbred lines. 相似文献