共查询到20条相似文献,搜索用时 390 毫秒
1.
U. Kumar A. K. Joshi S. Kumar R. Chand M. S. R?der 《Molecular breeding : new strategies in plant improvement》2010,26(3):477-491
Spot blotch caused by Bipolaris sorokiniana is a destructive disease of wheat in warm and humid wheat growing regions of the world. To identify quantitative trait loci
(QTLs) for spot blotch resistance, two mapping populations were developed by making the crosses between common susceptible
cultivar ‘Sonalika’ with the resistant breeding lines ‘Ning 8201’ and ‘Chirya 3’. Single seed descent derived F6, F7, F8 lines of the first cross ‘Ning 8201’ × ‘Sonalika’ were evaluated for resistance to spot blotch in three blocks in each of
the 3 years. After screening of 388 pairs of simple sequence repeat primers between the two parents, 119 polymorphic markers
were used to genotype the mapping population. Four QTLs were identified on the chromosomes 2AS, 2BS, 5BL and 7DS and explained
62.9% of phenotypic variation in a simultaneous fit. The QTL on chromosome 2A was detected only in 1 year and explained 22.7%
of phenotypic variation. In the second cross (‘Chirya 3’ × ‘Sonalika’), F7 and F8 population were evaluated in three blocks in each of the 2 years. In this population, five QTLs were identified on chromosomes
2BS, 2DS, 3BS, 7BS and 7DS. The QTLs identified in the ‘Chirya 3’ × ‘Sonalika’ population explained 43.4% of phenotypic variation
in a simultaneous fit. The alleles for reduced disease severity in both the populations were derived from the respective resistant
parent. The QTLs QSb.bhu-2B and QSb.bhu-7D from both populations were placed in the same deletion bins, 2BS1-0.53-0.75 and 7DS5-0.36-0.61, respectively. The closely
linked markers Xgwm148 to the QTL on chromosome 2B and Xgwm111 to the QTL on chromosome 7D are potentially diagnostic markers for spot blotch resistance. 相似文献
2.
Fusarium head blight (FHB) is one of the most devastating wheat diseases, causing both yield loss and quality reduction. To detect
quantitative trait loci (QTL) responsible for FHB resistance, plants of the F
2:3 population derived from a ‘Wangshui-bai’ × ‘Sy95-7’ cross were artificially inoculated. Of 396 simple sequence repeats (SSRs),
125 amplified fragment length polymorphisms were used for FHB resistance QTL analysis. Five QTLs for FHB resistance were detected
on chromosomes 3B, 6B, 7A, 1B and 2D. The effect of the QTL located on chromosome 3B on phenotypic variation was 31.69%, while
that of the QTL found on 2D was the smallest and only accounted for 4.98% of the variation. The resistance alleles originated
from ‘Wangshibai’ and association of the QTLs using these SSR markers may facilitate marker-assisted selection to improve
FHB resistance in the wheat breeding programs of southwest China. 相似文献
3.
Accumulation of additive effects generates a strong photoperiod sensitivity in the extremely late-heading rice cultivar ‘Nona Bokra’ 总被引:1,自引:0,他引:1
Uga Y Nonoue Y Liang ZW Lin HX Yamamoto S Yamanouchi U Yano M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(8):1457-1466
Many rice cultivars that originated from lower-latitude regions exhibit a strong photoperiod sensitivity (PS) and show extremely
late heading under long-day conditions. Under natural day-length conditions during the cropping season in Japan, the indica rice cultivar ‘Nona Bokra’ from India showed extremely late heading (202 days to heading) compared to the japonica cultivar ‘Koshihikari’ (105 days), from Japan. To elucidate the genetic factors associated with such extremely late heading,
we performed quantitative trait locus (QTL) analyses of heading date using an F2 population and seven advanced backcross progeny (one BC1F2 and six BC2F2) derived from a cross between ‘Nona Bokra’ and ‘Koshihikari’. The analyses revealed 12 QTLs on seven chromosomes. The ‘Nona
Bokra’ alleles of all QTLs contributed to an increase in heading date. Digenic interactions were rarely observed between QTLs.
Based on the genetic parameters of the QTLs, such as additive effects and percentage of phenotypic variance explained, these
12 QTLs are likely generate a large proportion of the phenotypic variation observed in the heading dates between ‘Nona Bokra’
and ‘Koshihikari’. Comparison of chromosomal locations between heading date QTLs detected in this study and QTLs previously
identified in ‘Nipponbare’ × ‘Kasalath’ populations revealed that eight of the heading date QTLs were recognized nearby the
Hd1, Hd2, Hd3a, Hd4, Hd5, Hd6, Hd9, and Hd13. These results suggest that the strong PS in ‘Nona Bokra’ was generated mainly by the accumulation of additive effects of
particular alleles at previously identified QTLs. 相似文献
4.
QTL mapping for plant-height traits has not been hitherto reported in high-oil maize. A high-oil maize inbred ‘GY220’ was
crossed with two dent maize inbreds (‘8984’ and ‘8622’) to generate two connected F2:3 populations. Four plant-height traits were evaluated in 284 and 265 F2:3 families. Single-trait QTL mapping and multiple-trait joint QTL mapping was used to detect QTLs for the traits and the genetic
relationship between plant height (PH) and two other plant-height traits. A total of 28 QTLs and 12 pairs of digenic interactions
among detected QTLs for four traits were detected in the two F2:3 families. Only one marker was shared between the two populations. Joint analysis of PH with ear height (EH) and PH with top
height (TH) detected 32 additional QTLs. Our results showed that QTL detection for PH was dependent on the genetic background
of dent corn inbreds. Multiple-trait joint QTL analysis could increase the number of detected QTLs. 相似文献
5.
Fine mapping of quantitative trait loci Hd-1, Hd-2 and Hd-3, controlling heading date of rice, as single Mendelian factors 总被引:32,自引:0,他引:32
T. Yamamoto Y. Kuboki S. Y. Lin T. Sasaki M. Yano 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(1-2):37-44
Fine mapping was carried out on three putative QTLs (tentatively designated as Hd-1 to Hd-3) of five such QTLs controlling heading date in rice that had been earlier identified using an F2 population derived from a cross between a japonica variety, ‘Nipponbare’, and an indica variety, ‘Kasalath’, using progeny backcrossed with ‘Nipponbare’ as the recurrent parent. One BC3F2 and two BC3F1 plants, in which the target QTL regions were heterozygous and most other chromosomal regions were homozygous for the ‘Nipponbare’
allele, were selected as the experimental material. Self-pollinated progeny (BC3F2 and BC3F3) of the BC3F1 or BC3F2 showed continuous variation in days to heading. By means of progeny testing based on BC3F3 or BC3F4 lines, we determined the genotypes of each BC3F2 or BC3F3 individual at target QTLs. Their segregation patterns fitted Mendelian inheritance ratios. When the results obtained by RFLP
analysis and progeny tests were combined, Hd-1, Hd-2 and Hd-3 were mapped precisely on chromosomes 6, 7 and 6, respectively, of a rice RFLP linkage map. The results demonstrated that
QTLs can be treated as Mendelian factors. Moreover, these precise locations were in good agreement with the regions estimated
by QTL analysis of the initial F2 population, demonstrating the high reliability of QTL mapping using a high-density linkage map.
Received: 5 November 1997 / Accepted: 10 February 1998 相似文献
6.
Flavia M. Moreira Alberto Madini Rosanna Marino Luca Zulini Marco Stefanini Riccardo Velasco Pal Kozma M. Stella Grando 《Tree Genetics & Genomes》2011,7(1):153-167
Two populations (Pop) segregating quantitatively for resistance to downy mildew (DM), caused by Plasmopara viticola, were used to construct genetic maps and to carry out quantitative trait locus (QTL) analysis. Pop1 comprised of 174 F1 individuals from a cross of ‘Moscato Bianco’, a susceptible Vitis vinifera cultivar, and a resistant individual of Vitis riparia. Pop2 consisted of 94 progeny from a cross of two interspecific hybrids, ‘VRH3082 1-42’ and ‘SK77 5/3’, with resistance traits
inherited from Vitis rotundifolia and Vitis amurensis, respectively. Resistance of progeny was measured in field and greenhouse conditions by visual evaluation of disease symptoms
on leaves. Linkage maps of 1037.2 and 651 cM were built essentially with simple sequence repeat markers and were enriched
with gene-derived single-strand conformational polymorphism and single-nucleotide polymorphism markers. Simple interval mapping
and Kruskall–Wallis analysis detected a stable QTL involved in field resistance to DM on linkage group (LG) 7 of the Pop1
integrated map co-localized with a putative Caffeoyl-CoA O-methyltransferase-derived marker. Additional QTLs were detected on LGs 8, 12 and 17. We were able to identify genetic factors
correlated with resistance to P. viticola with lower statistical significance on LGs 1, 6 and 7 of the Pop2 map. Finally, no common QTLs were found between the two
crosses analyzed. A search of the grapevine genome sequence revealed either homologues to non-host-, host- or defense-signalling
genes within the QTL intervals. These positional candidate genes may provide new information about chromosomal regions hosting
phenotypic loci. 相似文献
7.
Pilson Choi Yoshiro Mano Atsuko Ishikawa Masashi Odashima Taishi Umezawa Tatsuhito Fujimura Yoshihito Takahata Takao Komatsuda 《Plant biotechnology reports》2010,4(1):23-27
Quantitative trait loci (QTLs) controlling ability of somatic embryogenesis were identified in soybean. A frame map with 204-point
markers was developed using an RI population consisting of 117 F11 lines derived from a cross between cultivar ‘Keburi’ and a weedy soybean ‘Masshokutou Kou 502’. The parents differed greatly
in their abilities of somatic embryogenesis using immature cotyledons as explants. The ability of somatic embryogenesis was
evaluated in five different experiments: the F11 (evaluated in 1998) and F15 (2002) generations cultured on basal media supplemented with 40 mg l−1 2,4-D (2,4-D1998 and 2,4-D2002), F14 (2001) generation on medium with 40 mg l−1 2,4-D and high sucrose concentration [2,4-D2001 (30 g l−1 sucrose)], and the F11 (1998) and F12 (1999) generations on medium with 10 mg l−1 NAA (NAA1998 and NAA1999). The RILs showed wide and continuous variations in each of the five experiments. In the composite
interval mapping analysis, 2 QTLs were found in group 8 (D1b + W, LOD = 5.42, r
2 = 37.5) in the experiment of 2,4-D1998 and in group 6 (C2, LOD = 6.03, r
2 = 26.0) in the experiment of 2,4-D2001 (high concentration sucrose). In both QTLs, alleles of ‘Masshokutou Kou 502’ with
high ability of somatic embryogenesis contributed to the QTLs. For the other three experiments, no QTL was detected in the
criteria of LOD >3.0, suggesting the presence of minor genes. 相似文献
8.
Sibylle Stoeckli Karsten Mody Cesare Gessler Andrea Patocchi Mauro Jermini Silvia Dorn 《Tree Genetics & Genomes》2008,4(4):833-847
The rosy apple aphid (Dysaphis plantaginea), the leaf-curling aphid (Dysaphis cf. devecta) and the green apple aphid (Aphis pomi) are widespread pest insects that reduce growth of leaves, fruits and shoots in apple (Malus × domestica). Aphid control in apple orchards is generally achieved by insecticides, but alternative management options like growing
resistant cultivars are needed for a more sustainable integrated pest management (IPM). A linkage map available for a segregating
F1-cross of the apple cultivars ‘Fiesta’ and ‘Discovery’ was used to investigate the genetic basis of resistance to aphids.
Aphid infestation and plant growth characteristics were repeatedly assessed for the same 160 apple genotypes in three different
environments and 2 consecutive years. We identified amplified fragment length polymorphism (AFLP) markers linked to quantitative
trait loci (QTLs) for resistance to D. plantaginea (‘Fiesta’ linkage group 17, locus 57.7, marker E33M35–0269; heritability: 28.3%), and to D. cf. devecta (‘Fiesta’ linkage group 7, locus 4.5, marker E32M39–0195; heritability: 50.2%). Interactions between aphid species, differences
in climatic conditions and the spatial distribution of aphid infestation were identified as possible factors impeding the
detection of QTLs. A pedigree analysis of simple sequence repeat (SSR) marker alleles closely associated with the QTL markers
revealed the presence of the alleles in other apple cultivars with reported aphid resistance (‘Wagener’, ‘Cox’s Orange Pippin’),
highlighting the genetic basis and also the potential for gene pyramiding of aphid resistance in apple. Finally, significant
QTLs for shoot length and stem diameter were identified, while there was no relationship between aphid resistance and plant
trait QTLs.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
9.
Identification of molecular markers linked to quantitative trait loci for soybean resistance to corn earworm 总被引:7,自引:0,他引:7
B. G. Rector J. N. All W. A. Parrott H. R. Boerma 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(6-7):786-790
One hundred and thirty nine restriction fragment length polymorphisms (RFLPs) were used to construct a soybean (Glycine max L. Merr.) genetic linkage map and to identify quantitative trait loci (QTLs) associated with resistance to corn earworm (Helicoverpa zea Boddie) in a population of 103 F2-derived lines from a cross of ‘Cobb’ (susceptible) and PI229358 (resistant). The genetic linkage map consisted of 128 markers
which converged onto 30 linkage groups covering approximately 1325 cM. There were 11 unlinked markers. The F2-derived lines and the two parents were grown in the field under a plastic mesh cage near Athens, Ga., in 1995. The plants
were artificially infested with corn earworm and evaluated for the amount of defoliation. Using interval-mapping analysis
for linked markers and single-factor analysis of variance (ANOVA), markers were tested for an association with resistance.
One major and two minor QTLs for resistance were identified in this population. The PI229358 allele contributed insect resistance
at all three QTLs. The major QTL is linked to the RFLP marker A584 on linkage group (LG) ‘M’ of the USDA/Iowa State University
public soybean genetic map. It accounts for 37% of the total variation for resistance in this cross. The minor QTLs are linked
to the RFLP markers R249 (LG ‘H’) and Bng047 (LG ‘D1’). These markers explain 16% and 10% of variation, respectively. The
heritability (h2) for resistance was estimated as 64% in this population.
Received: 15 October 1997 / Accepted: 4 November 1997 相似文献
10.
Matsubara K Ando T Mizubayashi T Ito S Yano M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,115(2):179-186
One outcome of hybrid breakdown is poor growth, which we observed as a reduction in the number of panicles per plant and in
culm length in an F2 population derived from a cross between the genetically divergent rice (Oryza sativa L.) cultivars ‘Sasanishiki’ (japonica) and ‘Habataki’ (indica). Quantitative trait locus (QTL) analysis of the two traits and two-way ANOVA of the detected QTLs suggested that the poor
growth was due mainly to an epistatic interaction between genes at QTLs located on chromosomes 2 and 11. The poor growth was
likely to result when a plant was homozygous for the ‘Habataki’ allele at the QTL on chromosome 2 and homozygous for the ‘Sasanishiki’
allele at the QTL on chromosome 11. The results suggest that the poor growth found in the F2 population was due to hybrid breakdown of a set of complementary genes. To test this hypothesis and determine the precise
chromosomal location of the genes causing the hybrid breakdown, we performed genetic analyses using a chromosome segment substitution
line, in which a part of chromosome 2 from ‘Habataki’ was substituted into the genetic background of ‘Sasanishiki’. The segregation
patterns of poor growth in plants suggested that both of the genes underlying the hybrid breakdown were recessive. The gene
on chromosome 2, designated hybrid breakdown 2 (hbd2), was mapped between simple sequence repeat markers RM3515 and RM3730. The gene on chromosome 11, hbd3, was mapped between RM5824 and RM1341.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
11.
G. Pressoir L. Albar N. Ahmadi I. Rimbault M. Lorieux D. Fargette A. Ghesquière 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(7):1155-1161
The genetic basis of resistance to rice yellow mottle virus (RYMV) was studied in a doubled-haploid (DH) population derived
from a cross between the very susceptible indica variety ‘IR64’ and the resistant upland japonica variety Azucena. As a quantitative trait locus (QTL) involved in virus content estimated with an ELISA test has been previously
identified on chromosome 12, we performed a wide search for interactions between this QTL and the rest of the genome, and
between this QTL and morphological traits segregating in the population. Multiple regression with all identified genetic factors
was used to validate the interactions. Significant epistasis accounting for a major part of the total genetic variation was
observed. A complementary epistasis between the QTL located on chromosome 12 and a QTL located on chromosome 7 could be the
major genetic factor controlling the virus content. Resistance was also affected by a morphology-dependent mechanism since
tillering was interfering with the resistance mechanism conditioned by the epistasis between the two QTLs. Marker-assisted
backcross breeding was developed to introgress the QTLs of chromosome 7 and chromosome 12 in the susceptible ‘IR64’ genetic
background. First results confirmed that if both QTLs do not segregate in a backcross-derived F2 population, then the QTL of chromosome 12 cannot explain differences in virus content. A near-isogenic line (NIL) approach
is currently being developed to confirm the proposed genetic model of resistance to RYMV.
Received: 20 April 1990 / Accepted: 30 April 1998 相似文献
12.
Taguchi K Ogata N Kubo T Kawasaki S Mikami T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(2):227-234
Aphanomyces root rot, caused by Aphanomyces cochlioides Drechs., is one of the most serious diseases of sugar beet (Beta vulgaris L.). Identification and characterization of resistance genes is a major task in sugar beet breeding. To ensure the effectiveness
of marker-assisted screening for Aphanomyces root rot resistance, genetic analysis of mature plants’ phenotypic and molecular
markers’ segregation was carried out. At a highly infested field site, some 187 F2 and 66 F3 individuals, derived from a cross between lines ‘NK-310mm-O’ (highly resistant) and ‘NK-184mm-O’ (susceptible), were tested,
over two seasons, for their level of resistance to Aphanomyces root rot. This resistance was classified into six categories
according to the extent and intensity of whole plant symptoms. Simultaneously, two selected RAPD and 159 ‘NK-310mm-O’-coupled
AFLP were used in the construction of a linkage map of 695.7 cM. Each of nine resultant linkage groups was successfully anchored
to one of nine sugar beet chromosomes by incorporating 16 STS markers. Combining data for phenotype and molecular marker segregation,
a single QTL was identified on chromosome III. This QTL explained 20% of the variance in F2 population (in the year 2002) and 65% in F3 lines (2003), indicating that this QTL plays a major role in the Aphanomyces root rot resistance. This is the first report
of the genetic mapping of resistance to Aphanomyces-caused diseases in sugar beet. 相似文献
13.
Kazuhiro Sato Kiyosumi Hori Kazuyoshi Takeda 《Molecular breeding : new strategies in plant improvement》2008,22(4):517-526
Fusarium head blight (FHB) resistance was evaluated in five recombinant inbred (RI) populations. The RI populations consisted
of top-cross progeny derived from a diallel set of crosses. Each of five two-row barley lines differing in response to FHB
were crossed with ‘Harbin 2-row’. FHB severity was scored on an 11-point scale, where resistant = 0 and susceptible = 10,
based on the ‘cut-spike test’. Disease data were obtained for each population for 2 or 3 years. Linkage maps comprised of
expressed sequence tag (EST) markers were developed for each population and used for quantitative trait locus (QTL) detection.
Thirty two QTLs were detected using all data sets (individual populations and years). Thirteen QTLs were detected using averages
across years; 10 of these were consistent across the individual year and average data sets. These QTLs clustered at 14 regions,
with clusters on all chromosomes. At 11 of these clusters, Harbin 2-row contributed FHB resistance alleles. No QTLs were detected
near the row type (vrs1) locus in any of the five RI populations, suggesting that the FHB resistance QTL in this region reported in two-row × six-row
crosses may be pleiotropic effect of vrs1. QTL were coincident with the flowering type locus (cly1/Cly2) on chromosome 2H in every population. Some QTL × QTL interactions were significant, but these were smaller than QTL main
effects. Considering the pleiotropic effect of spike morphology on FHB resistance, future FHB resistance mapping efforts in
barley should focus on cross combinations in which alleles at vrs1 are not segregating.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
14.
Sibylle Stoeckli Karsten Mody Andrea Patocchi Markus Kellerhals Silvia Dorn 《Tree Genetics & Genomes》2009,5(1):257-267
The aim of this study was to assess the genetic basis of rust mite (Aculus schlechtendali) resistance in apple (Malus × domestica). A. schlechtendali infestation of apple trees has increased as a consequence of reduced side effects of modern fungicides on rust mites. An
analysis of quantitative trait loci (QTLs) was carried out using linkage map data available for F1 progeny plants of the cultivars ‘Fiesta’ × ‘Discovery’. Apple trees representing 160 different genotypes were surveyed for
rust mite infestation, each at three different sites in two consecutive years. The distribution of rust mites on the individual
apple genotypes was aggregated and significantly affected by apple genotype and site. We identified two QTLs for A. schlechtendali resistance on linkage group 7 of ‘Fiesta’. The AFLP marker E35M42-0146 (20.2 cM) and the RAPD marker AE10-400 (45.8 cM) were
closest positioned to the QTLs and explained between 11.0% and 16.6% of the phenotypic variability. Additionally, putative
QTLs on the ‘Discovery’ chromosomes 4, 5 and 8 were detected. The SSR marker Hi03a10 identified to be associated to one of
the QTLs (AFLP marker E35M42-0146) was traced back in the ‘Fiesta’ pedigree to the apple cultivar ‘Wagener’. This marker may
facilitate the breeding of resistant apple cultivars by marker assisted selection. Furthermore, the genetic background of
rust mite resistance in existing cultivars can be evaluated by testing them for the identified SSR marker.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
15.
K. Richter J. Schondelmaier C. Jung 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(8):1225-1234
Resistance loci for seedling-stage resistance to net blotch disease (Drechslera teres) in barley were mapped with molecular markers in an F2 population derived from a cross between the susceptible barley cultivar ‘Arena’ and the resistant Ethiopian landrace ‘Hor
9088’. Disease reactions were scored with first and second leaves of 2-week-old plants 7 and 9 days after inoculation with
a single spore-derived isolate. For linkage analysis, 22 RFLP markers and 284 AFLP markers were used. The seven linkage groups
covered 1153.3 cM with an average marker interval of 3.76 cM. The resistance was determined to be inherited in a quantitative
manner. Altogether, 12 QTLs were mapped with positions depending on the leaf used for testing and the time period after infection.
Heritability in the broad sense ranged between 0.21 and 0.37.
Received: 26 May 1998 / Accepted: 9 June 1998 相似文献
16.
Mitsuhiro Obara Wataru Tamura Takeshi Ebitani Masahiro Yano Tadashi Sato Tomoyuki Yamaya 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(3):535-547
Root system development is an important target for improving yield in cereal crops. Active root systems that can take up nutrients
more efficiently are essential for enhancing grain yield. In this study, we attempted to identify quantitative trait loci
(QTL) involved in root system development by measuring root length of rice seedlings grown in hydroponic culture. Reliable
growth conditions for estimating the root length were first established to renew nutrient solutions daily and supply NH4
+ as a single nitrogen source. Thirty-eight chromosome segment substitution lines derived from a cross between ‘Koshihikari’,
a japonica variety, and ‘Kasalath’, an indica variety, were used to detect QTL for seminal root length of seedlings grown in 5 or 500 μM NH4
+. Eight chromosomal regions were found to be involved in root elongation. Among them, the most effective QTL was detected
on a ‘Kasalath’ segment of SL-218, which was localized to the long-arm of chromosome 6. The ‘Kasalath’ allele at this QTL,
qRL6.1, greatly promoted root elongation under all NH4
+ concentrations tested. The genetic effect of this QTL was confirmed by analysis of the near-isogenic line (NIL) qRL6.1. The seminal root length of the NIL was 13.5–21.1% longer than that of ‘Koshihikari’ under different NH4
+ concentrations. Toward our goal of applying qRL6.1 in a molecular breeding program to enhance rice yield, a candidate genomic region of qRL6.1 was delimited within a 337 kb region in the ‘Nipponbare’ genome by means of progeny testing of F2 plants/F3 lines derived from a cross between SL-218 and ‘Koshihikari’. 相似文献
17.
F. Taguchi-Shiobara S. Y. Lin K. Tanno T. Komatsuda M. Yano T. Sasaki S. Oka 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(5-6):828-833
Quantitative trait loci (QTL) controlling the regeneration ability of rice seed callus were detected using 245 RFLP markers
and 98 BC1F5 lines derived from two varieties, ‘Nipponbare’ and ‘Kasalath’. Regeneration ability was evaluated by two indices: average
number of regenerated shoots per callus (NRS) and regeneration rate (RR). The BC1F5 lines showed continuous segregation for both indices. Five putative QTL for NRS (tentatively named qRg1, qRg2, qRg4a, qRg4b and qRg4c) located on chromosomes 1, 2 and 4 were detected. Digenic interaction among these detected QTL was not significant (P<0.01). Among the five QTL detected, four ‘Kasalath’ alleles and one ‘Nipponbare’ allele increased NRS. According to an estimate
based on the nearest marker loci, the five QTL accounted for 38.5% of the total phenotypic variation of the BC1F5 lines. For RR, four putative QTL were detected on chromosomes 2 and 4, and all of these were in the same chromosomal regions
as the NRS QTL. The four RR QTL accounted for 32.6% of the total phenotypic variation.
Received: 7 November 1996 / Accepted: 25 April 1997 相似文献
18.
Zorrilla-Fontanesi Y Cabeza A Domínguez P Medina JJ Valpuesta V Denoyes-Rothan B Sánchez-Sevilla JF Amaya I 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(5):755-778
Breeding for fruit quality traits in strawberry (Fragaria × ananassa, 2n = 8x = 56) is complex due to the polygenic nature of these traits and the octoploid constitution of this species. In order to
improve the efficiency of genotype selection, the identification of quantitative trait loci (QTL) and associated molecular
markers will constitute a valuable tool for breeding programs. However, the implementation of these markers in breeding programs
depends upon the complexity and stability of QTLs across different environments. In this work, the genetic control of 17 agronomical
and fruit quality traits was investigated in strawberry using a F1 population derived from an intraspecific cross between two contrasting selection lines, ‘232’ and ‘1392’. QTL analyses were
performed over three successive years based on the separate parental linkage maps and a pseudo-testcross strategy. The integrated
strawberry genetic map consists of 338 molecular markers covering 37 linkage groups, thus exceeding the 28 chromosomes. 33
QTLs were identified for 14 of the 17 studied traits and approximately 37% of them were stable over time. For each trait,
1–5 QTLs were identified with individual effects ranging between 9.2 and 30.5% of the phenotypic variation, indicating that
all analysed traits are complex and quantitatively inherited. Many QTLs controlling correlated traits were co-located in homoeology
group V, indicating linkage or pleiotropic effects of loci. Candidate genes for several QTLs controlling yield, anthocyanins,
firmness and l-ascorbic acid are proposed based on both their co-localization and predicted function. We also report conserved QTLs among
strawberry and other Rosaceae based on their syntenic location. 相似文献
19.
DNA marker analysis of loci conferring resistance to peanut root-knot nematode in soybean 总被引:4,自引:0,他引:4
J. P. Tamulonis B. M. Luzzi R. S. Hussey W. A. Parrott H. R. Boerma 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):664-670
Peanut root-knot nematode [Meloidogyne arenaria (Neal) Chitwood] (Ma) is a serious pathogen of soybean, Glycine max L. Merrill, in the southern USA. Breeding for root-knot nematode resistance is an important objective in many plant breeding
programs. The inheritance of soybean resistance to Ma is quantitative and has a moderate-to-high variance-component heritability
on a family mean basis. The objectives of the present study were to use restriction fragment length polymorphism (RFLP) markers
to identify quantitative trait loci (QTLs) conferring resistance to Ma and to determine the genomic location and the relative
contribution to resistance of each QTL. An F2 population from a cross between PI200538 (Ma resistant) and ‘CNS’ (Ma susceptible) was mapped with 130 RFLPs. The 130 markers
converged on 20 linkage groups spanning a total of 1766 cM. One hundred and five F2:3 families were grown in the greenhouse and inoculated with Ma Race 2. Two QTLs conferring resistance to Ma were identified
and PI200538 contributed the alleles for resistance at both QTLs. One QTL was mapped at 0-cM recombination with marker B212V-1
on linkage group-F (LG-F) of the USDA/ARS-Iowa State University RFLP map, and accounted for 32% of the variation in gall number.
Another QTL was mapped in the interval from B212D-2 to A111H-2 on LG-E, and accounted for 16% of the variation in gall number.
Gene action for the QTL located on LG-F was additive to partially dominant, whereas the gene action for the QTL on LG-E was
dominant with respect to resistance. The two QTLs, when fixed on the framework map, accounted for 51% of the variation in
gall number in a two-QTL model. The two QTLs for Ma resistance were found in duplicated regions of the soybean genome, and
the major QTL for Ma resistance on LG-F is positioned within a cluster of eight diverse disease-resistance loci.
Received: 10 June 1996 / Accepted: 18 April 1997 相似文献
20.
A major QTL for resistance to Gibberella stalk rot in maize 总被引:1,自引:0,他引:1
Qin Yang Guangming Yin Yanling Guo Dongfeng Zhang Shaojiang Chen Mingliang Xu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(4):673-687
Fusarium graminearum Schwabe, the conidial form of Gibberella zeae, is the causal fungal pathogen responsible for Gibberella stalk rot of maize. Using a BC1F1 backcross mapping population derived from a cross between ‘1145’ (donor parent, completely resistant) and ‘Y331’ (recurrent
parent, highly susceptible), two quantitative trait loci (QTLs), qRfg1 and qRfg2, conferring resistance to Gibberella stalk rot have been detected. The major QTL qRfg1 was further confirmed in the double haploid, F2, BC2F1, and BC3F1 populations. Within a qRfg1 confidence interval, single/low-copy bacterial artificial chromosome sequences, anchored expressed sequence tags, and insertion/deletion
polymorphisms, were exploited to develop 59 markers to saturate the qRfg1 region. A step by step narrowing-down strategy was adopted to pursue fine mapping of the qRfg1 locus. Recombinants within the qRfg1 region, screened from each backcross generation, were backcrossed to ‘Y331’ to produce the next backcross progenies. These
progenies were individually genotyped and evaluated for resistance to Gibberella stalk rot. Significant (or no significant) difference in resistance reactions between homozygous and heterozygous genotypes
in backcross progeny suggested presence (or absence) of qRfg1 in ‘1145’ donor fragments. The phenotypes were compared to sizes of donor fragments among recombinants to delimit the qRfg1 region. Sequential fine mapping of BC4F1 to BC6F1 generations enabled us to progressively refine the qRfg1 locus to a ~500-kb interval flanked by the markers SSR334 and SSR58. Meanwhile, resistance of qRfg1 to Gibberella stalk rot was also investigated in BC3F1 to BC6F1 generations. Once introgressed into the ‘Y331’ genome, the qRfg1 locus could steadily enhance the frequency of resistant plants by 32–43%. Hence, the qRfg1 locus was capable of improving maize resistance to Gibberella stalk rot. 相似文献