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1.
A major QTL conferring crown rot resistance in barley and its association with plant height 总被引:1,自引:0,他引:1
H. B. Li M. X. Zhou C. J. Liu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(5):903-910
Crown rot (CR) is one of the most destructive diseases of barley and wheat. Fusarium species causing CR survive in crop residue and a growing acceptance of stubble retention practices has exacerbated disease
severity and yield loss. Growing resistant cultivars has long been recognised as the most effective way to reduce CR damage
but these are not available in barley. In a routine screening of germplasm, a barley landrace from China gave the best CR
resistance among the genotypes tested. Using a doubled haploid population derived from this landrace crossed to Franklin,
we demonstrate that the CR resistance of TX9425 was conditioned by a major QTL. The QTL, designated as Qcrs.cpi-3H, was mapped near the centromere on the long arm of chromosome 3H. Its effect is highly significant, accounting for up to
63.3% of the phenotypic variation with a LOD value of 14.8. The location of Qcrs.cpi-3H was coincident with a major QTL conferring plant height (PH) and the effect of PH on CR reaction was also highly significant.
When the effect of PH was accounted for by covariance analysis, the Qcrs.cpi-3H QTL remained highly significant, accounting for over 40% of the phenotypic variation. The existence of such a major QTL implies
that breeding barley cultivars with enhanced CR resistance should be feasible. 相似文献
2.
Fusarium crown rot (FCR) is one of the most damaging cereal diseases in semi-arid regions worldwide. The genetics of FCR resistance in the bread wheat (Triticum eastivum L.) variety EGA Wylie, the most resistant commercial variety available, was studied by QTL mapping. Three populations of recombinant inbred lines were developed with this elite variety as the resistant parent. Four QTL conferring FCR resistance were detected and resistance alleles of all of them were derived from the resistant parent EGA Wylie. One of these loci was located on the short arm of chromosome 5D (designated as Qcrs.cpi-5D). This QTL explains up to 31.1% of the phenotypic variance with an LOD value of 9.6. The second locus was located on the long arm of chromosome 2D (designated as Qcrs.cpi-2D) and explained up to 20.2% of the phenotypic variance with an LOD value of 4.5. Significant effects of both Qcrs.cpi-5D and Qcrs.cpi-2D were detected in each of the three populations assessed. Another two QTL (designated as Qcrs.cpi-4B.1 and Qcrs.cpi-4B.2, respectively) were located on the short arm of chromosome 4B. These two QTL explained up to 16.9% and 18.8% of phenotypic variance, respectively. However, significant effects of Qcrs.cpi-4B.1 and Qcrs.cpi-4B.2 were not detected when the effects of plant height was accounted for by covariance analysis. The elite characteristics of this commercial variety should facilitate the incorporation of the resistance loci it contains into breeding programs. 相似文献
3.
Guangdeng Chen Yaxi Liu Jun Ma Zhi Zheng Yuming Wei C. Lynne McIntyre You-Liang Zheng Chunji Liu 《PloS one》2013,8(3)
Fusarium crown rot (FCR), caused by various Fusarium species, is a destructive disease of cereal crops in semiarid regions worldwide. As part of our contribution to the development of Fusarium resistant cultivars, we identified several novel sources of resistance by systematically assessing barley genotypes representing different geographical origins and plant types. One of these sources of resistance was investigated in this study by generating and analysing two populations of recombinant inbred lines. A major locus conferring FCR resistance, designated as Qcrs.cpi-4H, was detected in one of the populations (mapping population) and the effects of the QTL was confirmed in the other population. The QTL was mapped to the distal end of chromosome arm 4HL and it is effective against both of the Fusarium isolates tested, one F. pseudograminearum and the other F. graminearum. The QTL explains up to 45.3% of the phenotypic variance. As distinct from an earlier report which demonstrated co-locations of loci conferring FCR resistance and plant height in barley, a correlation between these two traits was not detected in the mapping population. However, as observed in a screen of random genotypes, an association between FCR resistance and plant growth rate was detected and a QTL controlling the latter was detected near the Qcrs.cpi-4H locus in the mapping population. Existing data indicate that, although growth rate may affect FCR resistance, different genes at this locus are likely involved in controlling these two traits. 相似文献
4.
Martin Löffler Chris-Carolin Schön Thomas Miedaner 《Molecular breeding : new strategies in plant improvement》2009,23(3):473-488
Fusarium head blight (FHB) in wheat results in reduced yield and quality and in accumulation of mycotoxins. The objective of this
study was to identify genomic regions in wheat involved in the control of FHB resistance applying a QTL meta-analysis approach
by combining QTL of 30 mapping populations to propose independent meta-QTL (MQTL). A consensus map was created on which initial
QTL were projected. Nineteen MQTL comprising 2–13 initial QTL with widely varying confidence intervals were found on 12 chromosomes.
Some of them coincided with genomic regions previously identified (e.g. chromosomes 3BS, 6B), however, some MQTL were newly
detected by this study. Separate analysis of populations with the same resistant parent showed a rather high consistency for
the Chinese spring wheat donor ‘Sumai 3’, but little consistency for the Chinese donor ‘Wangshuibai’ and the Swiss donor ‘Arina’.
According to our results breeders can in future (1) choose parents for crossing not comprising the same resistance loci or
QTL intervals, (2) exploit new MQTL, and (3) select markers of some of these MQTL to be used in marker-assisted selection.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
5.
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
6.
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
7.
Uttam Kumar Arun K. Joshi Sundeep Kumar Ramesh Chand Marion S. Röder 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(4):783-792
Spot blotch caused by Bipolaris sorokiniana is a destructive disease of wheat in warm and humid wheat growing regions of the world. The development of disease resistant
cultivars is considered as the most effective control strategy for spot blotch. An intervarietal mapping population in the
form of recombinant inbred lines (RILs) was developed from a cross ‘Yangmai 6’ (a Chinese source of resistance) × ‘Sonalika’
(a spot blotch susceptible cultivar). The 139 single seed descent (SSD) derived F6, F7, F8 lines of ‘Yangmai 6’ × ‘Sonalika’ were evaluated for resistance to spot blotch in three blocks in each of the 3 years. Joint
and/or single year analysis by composite interval mapping (CIM) and likelihood of odd ratio (LOD) >2.2, identified four quantitative
trait loci (QTL) on the chromosomes 2AL, 2BS, 5BL and 6DL. These QTLs were designated as QSb.bhu-2A, QSb.bhu-2B, QSb.bhu-5B and QSb.bhu-6D, respectively. A total of 63.10% of phenotypic variation was explained by these QTLs based on the mean over years. Two QTLs
on chromosomes 2B and 5B with major effects were consistent over 3 years. All QTL alleles for resistance were derived from
the resistant parent ‘Yangmai 6’. 相似文献
8.
H. Buerstmayr M. Lemmens G. Fedak P. Ruckenbauer Communicated B. S. Gill 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(1):76-85
Fusarium head blight (FHB or scab) caused by Fusarium spp. is a widespread disease of cereals causing yield and quality losses and contaminating cereal products with mycotoxins. The
breeding of resistant varieties is the method of choice for controlling the disease. Unfortunately, the genetic basis of scab
resistance is still poorly understood. We present the results of a back-cross reciprocal monosomic analysis of FHB resistance
using the highly resistant Hungarian winter wheat line ‘U-136.1’ and the highly susceptible cultivar ‘Hobbit-sib’. Resistance
testing was performed in a field trial artificially inoculated with a Fusarium culmorum conidial suspension. Five hemizygous families containing ‘U-136.1’ chromosomes 6B, 5A, 6D, 1B, and 4B had a visually reduced
spread of infection compared to lines having the ‘Hobbit-sib’ chromosome. Chromosome 2B from ‘U-136.1’ had an increased spread
of infection. The critical chromosomes controlling seed weight were 6D, 3B, 5A, and 6B while those controlling deoxynivalenol
(DON) content were homoeologous groups 2 and 6, although the latter effects were not significant due to a high coefficient
of variation. Results from this and other studies show that chromosomes 6D, 6B, 5A, 4D, and 7A have frequently been associated
with scab resistance in a number of wheat cultivars. Research groups now attempting to map scab resistance in wheat using
markers should pay special attention to the above-mentioned chromosomes.
Received: 31 March 1998 / Accepted: 14 July 1998 相似文献
9.
Delourme R Piel N Horvais R Pouilly N Domin C Vallée P Falentin C Manzanares-Dauleux MJ Renard M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,117(7):1055-1067
The most common and effective way to control phoma stem canker (blackleg) caused by Leptosphaeria maculans in oilseed rape (Brassica napus) is by breeding resistant cultivars. Specific resistance genes have been identified in B. napus and related species but in some B. napus cultivars resistance is polygenic [mediated by quantitative trait loci (QTL)], postulated to be race non-specific and durable.
The genetic basis of quantitative resistance in the French winter oilseed rape ‘Darmor’, which was derived from ‘Jet Neuf’,
was previously examined in two genetic backgrounds. Stable QTL involved in blackleg resistance across year and genetic backgrounds
were identified. In this study, near isogenic lines (NILs) were produced in the susceptible background ‘Yudal’ for four of
these QTL using marker-assisted selection. Various strategies were used to develop new molecular markers, which were mapped
in these QTL regions. These were used to characterize the length and homozygosity of the ‘Darmor-bzh’ introgressed segment in the NILs. Individuals from each NIL were evaluated in blackleg disease field trials and assessed
for their level of stem canker in comparison to the recurrent line ‘Yudal’. The effect of QTL LmA2 was clearly validated and to a lesser extent, QTL LmA9 also showed an effect on the disease level. This work provides valuable material that can be used to study the mode of action
of genetic factors involved in L. maculans quantitative resistance. 相似文献
10.
L. Albar M. Lorieux N. Ahmadi I. Rimbault A. Pinel A. A. Sy D. Fargette A. Ghesquière 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(7):1145-1154
Rice yellow mottle virus (RYMV) resistance QTLs were mapped in a doubled-haploid population of rice, ‘IR64/Azucena’. Disease
impact on plant morphology and development, expression of symptoms and virus content were evaluated in field conditions. Virus
content was also assessed in a growth chamber. RYMV resistance was found to be under a polygenic determinism, and 15 QTLs
were detected on seven chromosomal fragments. For all of the resistance QTLs detected, the favourable allele was provided
by the resistant parent ‘Azucena’. Three regions were determined using different resistance parameters and in two environments.
On chromosome 12, a QTL of resistance that had already been detected in this population and another indica/japonica population was confirmed both in the field and under controlled conditions. Significant correlations were observed between
resistance and tillering ability, as measured on control non-inoculated plants. In addition, the three genomic fragments involved
in resistance were also involved in plant architecture and development. In particular, the semi-dwarfing gene sd-1, on chromosome 1, provided by the susceptible parent, ‘IR64’, mapped in a region where resistance QTLs were detected with
most of the resistance parameters. In contrast, the QTL of resistance mapped on chromosome 12 was found to be independent
of plant morphology.
Received: 20 April 1998 / Accepted: 30 April 1998 相似文献
11.
Fusarium head blight (FHB) caused by Fusarium graminearum and F. culmorum is a devastating disease with high effects on grain yield and quality. We developed spring wheat lines incorporating the highly effective FHB resistance quantitative trait loci (QTL) Fhb1 and Qfhs.ifa‐5A. Whether these QTL lead to competition within Fusarium populations in the field resulting in isolates with higher aggressiveness has not been analysed. The aims of this study were to determine (i) the aggressiveness potential of F. graminearum and F. culmorum isolates, (ii) competition effects of these isolates in binary mixtures and (iii) the stability of resistant hosts. Six F. graminearum, two F. culmorum isolates and seven binary mixtures containing these isolates were tested for their aggressiveness and mycotoxin production at two locations in South Germany in 2007 and 2008. Host lines were four spring wheat lines containing the resistance QTL Fhb1 and/or Qfhs.ifa‐5A or none of them and one standard variety. Re‐isolates were sampled from plots inoculated with the binary mixtures to identify the percentage of each isolate in the mixture by simple sequence repeat markers. Resistant host lines reacted as expected and had a high stability to all isolates and mixtures. Only less important host × mixture interactions were detected. Aggressiveness among isolates and mixtures was significantly different. Type and amount of mycotoxin and high single isolate aggressiveness were not necessarily advantageous in the mixture. However, both F. culmorum isolates outcompeted F. graminearum isolates. Significant deviations from the inoculated 1 : 1 proportions occurred in 34 of 49 cases, illustrating that competition effects appeared in the mixtures. These differences depended mainly on the year and not on the level of host resistance. We conclude that resistance should not be affected by the Fusarium isolates and mixtures. 相似文献
12.
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
13.
14.
Samreen Kazi J. Shultz J. Afzal Rizwan Hashmi Mohammed Jasim Jason Bond Prakash R. Arelli David A. Lightfoot 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(3):633-644
Soybean [Glycine max (L.) Merr.] cultivars varied in their resistance to different populations of the soybean cyst nematode (SCN), Heterodera glycines, called HG Types. The rhg1 locus on linkage group G was necessary for resistance to all HG types. However, the loci for resistance to H. glycines HG Type 1.3- (race 14) and HG Type 1.2.5- (race 2) of the soybean cyst nematode have varied in their reported locations.
The aims were to compare the inheritance of resistance to three nematode HG Types in a population segregating for resistance
to SCN and to identify the underlying quantitative trait loci (QTL). ‘Hartwig’, a soybean cultivar resistant to most SCN HG
Types, was crossed with the susceptible cultivar ‘Flyer’. A total of 92 F5-derived recombinant inbred lines (RILs; or inbred
lines) and 144 molecular markers were used for map development. The rhg1 associated QTL found in earlier studies were confirmed and shown to underlie resistance to all three HG Types in RILs (Satt309;
HG Type 0, P = 0.0001 R
2 = 22%; Satt275; HG Type 1.3, P = 0.001, R
2 = 14%) and near isogeneic lines (NILs; or iso-lines; Satt309; HG Type 1.2.5-, P = 0.001 R
2 = 24%). A new QTL underlying resistance to HG Type 1.2.5- was detected on LG D2 (Satt574; P = 0.001, R
2 = 11%) among 14 RILs resistant to the other HG types. The locus was confirmed in a small NIL population consisting of 60
plants of ten genotypes (P = 0.04). This QTL (cqSCN-005) is located in an interval previously associated with resistance to both SDS leaf scorch from
‘Pyramid’ and ‘Ripley’ (cqSDS-001) and SCN HG Type 1.3- from Hartwig and Pyramid. The QTL detected will allow marker assisted
selection for multigenic resistance to complex nematode populations in combination with sudden death syndrome resistance (SDS)
and other agronomic traits. 相似文献
15.
The impact of moisture on the development of Fusarium head blight (FHB) and accumulation of deoxynivalenol (DON) in Fusarium-infected wheat was examined. The field experiments were designed as split-split-plot with five replicates. Main plots were
durations of mist-irrigation [14, 21, 28 and 35 days after inoculation (DAI)]; sub-plots were wheat cultivar; and sub-sub-plots
were F. graminearum isolates differing in aggressiveness and DON production capacity. The wheat cultivars ‘Alsen’ (moderately resistant), ‘2375’
(moderately susceptible) and ‘Wheaton’ (susceptible) were inoculated at anthesis. Severity of FHB was assessed 21 days after
inoculation. Visually scabby kernels (VSK) and mycotxin content (DON, 15-AcDON, 3-AcDON and nivalenol) were determined on
harvested grain. The damage to grain, as measured by VSK, was significantly lower in the treatments receiving the least amount
of mist-irrigation (14 DAI) suggesting that extended moisture promotes disease development. DON was, however, significantly
lower in the 35-DAI misting treatment than in treatments receiving less post-inoculation moisture. The reduction of DON observed
in treatments receiving extended mist-irrigation was greatest in ‘Wheaton’ which recorded the highest FHB severity, VSK and
DON of the cultivars examined. Our results suggest that DON and other trichothecenes may be reduced by late-season moisture
despite increased grain colonization. We suggest that leaching may explain much of the reduction of mycotoxins, and that differences
in tissue morphology and metabolism may determine the rate of leaching from specific tissues. 相似文献
16.
Schwander F Eibach R Fechter I Hausmann L Zyprian E Töpfer R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(1):163-176
A population derived from a cross between grapevine breeding strain Gf.Ga-52-42 and cultivar ‘Solaris’ consisting of 265 F1-individuals
was genetically mapped using SSR markers and screened for downy mildew resistance. Quantitative trait locus (QTL) analysis
revealed two strong QTLs on linkage groups (LGs) 18 and 09. The locus on LG 18 was found to be identical with the previously
described locus Rpv3 and is transmitted by Gf.Ga-52-42. ‘Solaris’ transmitted the resistance-related locus on LG 09 explaining up to 50% of the
phenotypic variation in the population. This downy mildew resistance locus is named Rpv10 for resistance to Plasmopara viticola. Rpv10 was initially introgressed from Vitis amurensis, a wild species of the Asian Vitis gene pool. The one-LOD supported confidence interval of the QTL spans a section of 2.1 centi Morgan (cM) corresponding to
314 kb in the reference genome PN40024 (12x). Eight resistance gene analogues (RGAs) of the NBS–LRR type and additional resistance-linked
genes are located in this region of PN40024. The F1 sub-population which contains the Rpv3 as well as the Rpv10 locus showed a significantly higher degree of resistance, indicating additive effects by pyramiding of resistance loci. Possibilities
for using the resistance locus Rpv10 in a grapevine breeding programme are discussed. Furthermore, the marker data revealed ‘Severnyi’ × ‘Muscat Ottonel’ as the
true parentage for the male parent of ‘Solaris’. 相似文献
17.
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
18.
Different hypotheses on the genetic control of the resistance to the plum pox virus (PPV) have been reported in apricot, but
there was a lack of agreement about the number of loci involved. In recent years, apricot genetic maps have been constructed
from progenies derived from ‘Stark Early Orange’ or ‘Goldrich’, two main sources of resistance, three of these including the
mapping of the PPV resistance loci. As the location of the locus was not precisely established, we mapped the PPV resistance
loci using interval mapping (IM), composite interval mapping (CIM), and the Kruskal–Wallis non-parametric test in the F1 progeny derived from a cross between the susceptible cv. ‘Polonais’ and ’Stark Early Orange’. Four genomic regions were identified
as being involved in PPV resistance. One of these mapped to the upper region of linkage group 1 of ‘Stark Early Orange’, and
accounted for 56% of the phenotypic variation. Its location was similar to the one previously identified in ‘Goldrich’ and
Prunus davidiana. In addition, a gene strongly associated to these major quantitative trait loci (QTL) was found to be related to PPV infection.
Two putative QTLs were detected on linkage groups 3 of ‘Polonais’ and 5 of both ‘Polonais’ and ‘Stark Early Orange’ with both
parametric and non-parametric methods at logarithm of odds (LOD) scores slightly above the detection threshold. The last QTL
was only detected in the early stage of the infection. PPV resistance is, thus, controlled by a major dominant factor located
on linkage group 1. The hypothesis of recessive factors with lower effect is discussed. 相似文献
19.
Yusaku Uga Kazutoshi Okuno Masahiro Yano 《Molecular breeding : new strategies in plant improvement》2010,26(3):533-538
The stele (root vascular cylinder) in plants plays an important role in the transport of water and nutrients from the root
to the shoot. A quantitative trait locus (QTL) on rice chromosome 9 that controls stele transversal area (STA) was previously
detected in an F3 mapping population derived from a cross between the lowland cultivar ‘IR64’, with a small STA, and the upland cultivar ‘Kinandang
Patong’, with a large STA. To identify the gene(s) underlying this QTL, we undertook fine mapping of the locus. We screened
eight plants from BC2F3 lines in which recombination occurred near the QTL. Progeny testing of BC2F4 plants was used to determine the genotype classes for the QTL in each BC2F3 line. Accordingly, the STA QTL Sta1 (Stele Transversal Area 1) was mapped between the InDel markers ID07_12 and ID07_14. A candidate genomic region for Sta1 was defined more precisely between markers RM566 and RM24334, which delimit a 359-kb interval in the reference cultivar ‘Nipponbare’.
A line homozygous for the ‘Kinandang Patong’ allele of Sta1 had an STA approximately 28.4% larger than that of ‘IR64’. However, Sta1 did not influence maximum or total root length, suggesting that this QTL specifically controls STA. 相似文献
20.
Riaz S Tenscher AC Ramming DW Walker MA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(6):1059-1073
A limited genetic mapping strategy based on simple sequence repeat (SSR) marker data was used with five grape populations
segregating for powdery mildew (Erysiphe necator) resistance in an effort to develop genetic markers from multiple sources and enable the pyramiding of resistance loci. Three
populations derived their resistance from Muscadinia rotundifolia ‘Magnolia’. The first population (06708) had 97 progeny and was screened with 137 SSR markers from seven chromosomes (4,
7, 9, 12, 13, 15, and 18) that have been reported to be associated with powdery or downy mildew resistance. A genetic map
was constructed using the pseudo-testcross strategy and QTL analysis was carried out. Only markers from chromosome 13 and
18 were mapped in the second (04327) and third (06712) populations, which had 47 and 80 progeny, respectively. Significant
QTLs for powdery mildew resistance with overlapping genomic regions were identified for different tissue types (leaf, stem,
rachis, and berry) on chromosome 18, which distinguishes the resistance in ‘Magnolia’ from that present in other accessions
of M. rotundifolia and controlled by the Run1 gene on chromosome 12. The ‘Magnolia’ resistance locus was termed as Run2.1. Powdery mildew resistance was also mapped in a fourth population (08391), which had 255 progeny and resistance from M. rotundifolia ‘Trayshed’. A locus accounting for 50% of the phenotypic variation mapped to chromosome 18 and was named Run2.2. This locus overlapped the region found in the ‘Magnolia’-based populations, but the allele sizes of the flanking markers
were different. ‘Trayshed’ and ‘Magnolia’ shared at least one allele for 68% of the tested markers, but alleles of the other
32% of the markers were not shared indicating that the two M. rotundifolia selections were very different. The last population, 08306 with 42 progeny, derived its resistance from a selection Vitis romanetii C166-043. Genetic mapping discovered a major powdery mildew resistance locus termed Ren4 on chromosome 18, which explained 70% of the phenotypic variation in the same region of chromosome 18 found in the two M. rotundifolia resistant accessions. The mapping results indicate that powdery mildew resistance genes from different backgrounds reside
on chromosome 18, and that genetic markers can be used as a powerful tool to pyramid these loci and other powdery mildew resistance
loci into a single line. 相似文献