共查询到20条相似文献,搜索用时 31 毫秒
1.
J. L. Gonzalez-Hernandez P. K. Singh M. Mergoum T. B. Adhikari S. F. Kianian S. Simsek E. M. Elias 《Euphytica》2009,166(2):199-206
Stagonospora nodorum blotch (SNB) is an important foliar disease of durum wheat (Triticum turgidum var. durum) worldwide. The combined effects of SNB and tan spot, considered as components of the leaf spotting disease complex,
result in significant damage to wheat production in the northern Great Plains of North America. The main objective of this
study was the genetic analysis of resistance to SNB caused by Phaeosphaeria nodorum in tetraploid wheat, and its association with tan spot caused by Pyrenophora tritici-repentis race 2. The 133 recombinant inbred chromosome lines (RICL) developed from the cross LDN/LDN(Dic-5B) were evaluated for SNB
reaction at the seedling stage under greenhouse conditions. Molecular markers were used to map a quantitative trait locus
(QTL) on chromosome 5B, explaining 37.6% of the phenotypic variation in SNB reaction. The location of the QTL was 8.8 cM distal
to the tsn1 locus coding for resistance to P. tritici-repentis race 2. The presence of genes for resistance to both SNB and tan spot in close proximity in tetraploid wheat and the identification
of molecular markers linked to these genes or QTLs will be useful for incorporating resistance to these diseases in wheat
breeding programs. 相似文献
2.
Shu-Jun Wu Huan Zhong Yong Zhou Hui Zuo Li-Hui Zhou Jin-Yan Zhu Cao-Qiu Ji Shi-Liang Gu Ming-Hong Gu Guo-Hua Liang 《Euphytica》2009,165(3):557-565
The indica variety Dular has a high level of resistance to rice stripe virus (RSV). We performed quantitative trait locus (QTL) analysis
for RSV resistance using 226 F2 clonal lines at the seedling stage derived from a cross between the susceptible japonica variety Balilla and the resistant indica variety Dular with two evaluation criteria, infection rate (IR) and disease rating index (DRI). The experiments were performed
in both 2004 and 2005. Based on IR, three putative QTLs were detected and had consistent locations in the 2 years, one QTL
was detected in the RM7324–RM3586 interval on chromosome 3. The other two QTLs were linked and located in the RM287–RM209
and RM209–RM21 intervals on the long arm of chromosome 11, and accounted for 87.8–57.8% of the total phenotypic variation
in both years. Based on DRI, three putative QTLs were also detected and had consistent locations in both years. One of them
was located in the RM1124–SSR20 interval on the short arm of chromosome 11, while the other two linked QTLs had the same chromosomal
locations on chromosome 11 as those detected by IR, and accounted for 55.7–42.9% of total phenotypic variation in both years.
In comparison to the mapping results from previous studies, one of the two linked QTLs had a chromosomal location that was
similar to Stv-b
i
, an important RSV resistance gene, while the other appeared to be a newly reported one. 相似文献
3.
Summary Fusarium head blight (FHB) is a serious disease of wheat worldwide that may cause substantial yield and quality losses. Breeding for FHB-resistant cultivars is the most cost-effective approach to control FHB. The objective of the present study was to determine the relationship of resistance between new resistant sources and Sumai 3 using five simple sequence repeat (SSR) markers closely linked to the major QTL for FHB resistance on chromosome arms 3BS and 6BS. All five SSR markers were highly polymorphic between Sumai 3 (and its derivatives) and susceptible Canadian wheat lines. Most of the Sumai 3-derived Chinese wheat accessions and three Canadian FHB-resistant lines had all the Sumai 3 SSR marker alleles on chromosome arms 3BS and 6BS. The Chinese landrace Wangshuibai and two Japanese accessions Nobeokabozu and Nyu Bai had the same banding patterns as Sumai 3 for all five SSR marker alleles, and another Chinese landrace Fangshanmai had three of the five SSR markers in common with Sumai 3, and therefore most likely carries the same QTL as Sumai 3 on 3BS and 6BS. The Brazilian cultivar Frontana had no alleles in common with Sumai 3 on either QTL, and the Chinese landrace Hongheshang had only one of the five SSR markers in common with Sumai 3, therefore likely carrying resistance genes different from Sumai 3. The Italian cultivar Funo is not the donor of either the 3BS QTL or 6BS QTL. All five SSR seem to be effective candidates for marker-assisted selection to increase the level of resistance to FHB in wheat breeding programs. 相似文献
4.
A doubled haploid barley (Hordeum vulgare L.) population from a cross between the cultivar `Ingrid' and the Ethiopian landrace `Abyssinian' was mapped by AFLP, RFLP,
SSR and STS markers and tested for resistance to isolates`4004', `2', `16-6', `17', `22' and `WRS 1872' of Rhynchosporium secalis (Oudem.) J.J. Davis, the causal agent of leaf scald. Resistance tests were conducted on parents, DH-lines, a near-isogenic
line of `Abyssinian' (NIL) into `Ingrid', and an F2 population descended from the same F1 plants as the DHs. The DH population segregated for at least two major R. secalis resistance QTL. All isolates tested identified a major QTL on chromosome 3 (3H) associated with R. secalis resistance, in a 4 cM support interval between the co-segregating markers Bmac0209/Falc666 and MWG680. The QTL was linked
with the markers Falc666 (2.3 cM), YLM/ylp (0.3 cM), MWG680 (1.7 cM), cttaca2 (2.5 cM) and agtc17 (9.8 cM). The second QTL
was located on chromosome 1 (7H).However, this QTL was only detected by one isolate and was located in an interval of 16 cM
in the distal part of the chromosome. At this QTL the allele for improved scald resistance originated from the parent `Ingrid'.
There were a number of minor QTL on chromosomes 2 (2H), 4 (4H) and 6 (6H) that were not repeatable either across replications
or analysis methods. The importance of checking QTL-models by cross-validation is stressed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
Aluminium (Al) toxicity is a major constraint to crop productivity in acidic soils. A quantitative trait locus (QTL) analysis
was performed to identify the genetic basis of Al tolerance in the wheat cultivar ‘Chinese Spring’. A nutrient solution culture
approach was undertaken with the root tolerance index (RTI) and hematoxylin staining method as parameters to assess the Al
tolerance. Using a set of D genome introgression lines, a major Al tolerance QTL was located on chromosome arm 4DL, explaining
31% of the phenotypic variance present in the population. A doubled haploid population was used to map a second major Al tolerance
QTL to chromosome arm 3BL. This major QTL (Qalt
CS
.ipk-3B) in ‘Chinese Spring’ accounted for 49% of the phenotypic variation. Linkage of this latter QTL to SSR markers opens the possibility
to apply marker-assisted selection (MAS) and pyramiding of this new QTL to improve the Al tolerance of wheat cultivars in
breeding programmes. 相似文献
6.
Yong Xue Jianmin Wan Ling Jiang Chunming Wang Linglong Liu Yuan-ming Zhang Huqu Zhai 《Euphytica》2006,150(1-2):37-45
Summary Quantitative trait loci (QTL) analysis for Al tolerance was performed in rice using a mapping population of 98 BC1F10 lines (backcross inbred lines: BILs), derived from a cross of Al-tolerant cultivar of rice (Oryza sativa L. cv. Nipponbare) and Al-sensitive cultivar (cv. Kasalath). Three characters related to Al tolerance, including root elongation under non-stress conditions (CRE), root elongation under Al stress (SRE) and the relative root elongation (RRE) under Al stress versus non-stress conditions, were evaluated for the BILs and the parents at seedling stage. A total of seven QTLs for the three traits were identified. Among them, three putative QTLs for CRE (qCRE-6, qCRE-8 and qCRE-9) were mapped on chromosomes 6, 8 and 9, respectively. One QTL for SRE (qSRE-4) was identified on chromosome 4. Three QTLs (qRRE-5, qRRE-9 and qRRE-10) for RRE were detected on chromosomes 5, 9, 10 and accounted for 9.7–11.8% of total phenotypic variation. Interestingly, the QTL qRRE-5 appears to be syntenic with the genomic region carrying a major Al tolerance gene on chromosome 6 of maize. Another QTL, qRRE-9, appears to be similar among different rice populations, while qRRE-10 is unique in the BIL population. The common QTLs for CRE and RRE indicate that candidate genes conferring Al tolerance in the rice chromosome 9 may be associated with root growth rates. The existence of QTLs for Al tolerance was confirmed in substitution lines for corresponding chromosomal segments. These results also provide the possibilities of enhancing Al tolerance in rice through using marker-assisted selection (MAS) and pyramiding QTLs. 相似文献
7.
Botrytis grey mould (BGM) caused by Botrytis cinerea Pers. ex. Fr. is the second most important foliar disease of chickpea (Cicer arietinum L.) after ascochyta blight. An intraspecific linkage map of chickpea consisting of 144 markers assigned on 11 linkage groups
was constructed from recombinant inbred lines (RILs) of a cross that involved a moderately resistant kabuli cultivar ICCV
2 and a highly susceptible desi cultivar JG 62. The length of the map obtained was 442.8 cM with an average interval length
of 3.3 cM. Three quantitative trait loci (QTL) which together accounted for 43.6% of the variation for BGM resistance were
identified and mapped on two linkage groups. QTL1 explained about 12.8% of the phenotypic variation for BGM resistance and
was mapped on LG 6A. It was found tightly linked to markers SA14 and TS71rts36r at a LOD score of 3.7. QTL2 and QTL3 accounted
for 9.5 and 48% of the phenotypic variation for BGM resistance, respectively, and were mapped on LG 3. QTL 2 was identified
at LOD 2.7 and flanked by markers TA25 and TA144, positioned at 1 cM away from marker TA25. QTL3 was a strong QTL detected
at LOD 17.7 and was flanked by TA159 at 12 cM distance on one side and TA118 at 4 cM distance on the other side. This is the
first report on mapping of QTL for BGM resistance in chickpea. After proper validation, these QTL will be useful in marker-assisted
pyramiding of BGM resistance in chickpea. 相似文献
8.
Quantitative trait loci (QTLs) for resistance against non-parasitic leaf spots (NPLS) were first characterized in a spring barley double haploid population derived from the cross IPZ 24727/Barke (Behn et al., 2004). The aim of the present study was to identify QTLs for NPLS resistance in the half-sibling DH population IPZ 24727/Krona and to compare them with the QTLs of the population IPZ 24727/Barke. An anther culture-derived doubled haploid population of 536 DH lines was developed from the cross IPZ 24727 (resistant)/Krona (susceptible). Field trials were performed over two years in two replications, scoring NPLS and agronomic traits that might interact with NPLS. A molecular linkage map of 1035 cM was constructed based on AFLPs, SSRs and the mlo marker. QTL analyses for NPLS identified three QTLs that accounted for 30% of the phenotypic variation. For comparison of the QTLs from each DH population, a consensus map was generated comprising 277 markers with a length of 1199 cM. In both populations, the QTLs for NPLS mapped to chromosomes 1H, 4H and 7H. A common QTL with a great effect in both populations and over all environments was localized at the mlo locus on chromosome 4H, indicating that the mlo powdery mildew resistance locus has a considerable effect on NPLS susceptibility. The steps necessary to validate the QTLs and to improve the NPLS resistance by breeding were discussed. 相似文献
9.
K. Selvaraju P. Shanmugasundaram S. Mohankumar M. Asaithambi R. Balasaraswathi 《Euphytica》2007,157(1-2):35-43
Rice leaffolder (RLF) (Cnaphalocrocis medinalis (Guenée) is a destructive and widespread insect pest throughout the rice growing regions in Asia. The genetics of resistance
to RLF in rice is very complex and not thoroughly explored. The present study was conducted to detect the quantitative trait
loci (QTL) associated with RLF resistance involving 176 recombinant inbred lines (RILs) of F8 generation derived from a cross between IR36, a leaffolder susceptible variety and TNAULFR831311, a moderately resistant
indica rice culture. Simple sequence repeat (SSR) markers were used to construct specific linkage groups of rice. All the RILs were
screened to assess their level of resistance to RLF by measuring the leaf area damaged. Besides this, the length and width
of the flag leaf of each RIL were measured since these two parameters were considered as correlated traits to the RLF resistance
in rice. All the above parameters observed across the RILs showed quantitative variation. Correlation analysis revealed that
damage score based on greenhouse screening was positively correlated with length and width of the flag leaf. Out of 364 SSR
markers analysed, 90 were polymorphic between the parents. Multi-point analysis carried out on segregating 69 SSR marker loci
linkage group wise resulted in construction of linkage map with eleven groups of 42 SSR markers. Through single marker analysis,
19 SSR markers were found to have putative association with the three phenotypic traits studied. Of these markers, RM472 was
identified as a locus having major effect on RLF resistance trait based on length of the flag leaf. Interval mapping detected
two QTLs on linkage group 1. Among these QTLs, the QTL flanked by RM576–RM3412 were found to be associated with width of the
flag leaf and RLF resistance. The putative SSR markers associated with leaffolder resistance identified in the present study
may be one of the loci contributing resistance to RLF in rice. 相似文献
10.
Sugarcane mosaic virus (SCMV) is one of devastating pathogens in maize (Zea mays L.), and causes serious yield loss in susceptible cultivars. An effective solution to control the virus is utilizing resistant
genes to improve the resistance of susceptible materials, whereas the basic work is to analyze the genetic basis of resistance.
In this study, maize inbred lines Huangzao4 (resistant) and Mo17 (susceptible) were used to establish an F9 immortal recombinant inbred line (RIL) population containing 239 RILs. Based on this segregation population, a genetic map
was constructed with 100 simple sequence repeat (SSR) markers selected from 370 markers, and it covers 1421.5 cM of genetic
distance on ten chromosomes, with an average interval length of 14.2 cM. Analysis of the genetic map and resistance by mapping
software indicated that a major quantitative trait locus (QTL) was between bin6.00 and bin6.01 on chromosome 6, linked with
marker Bnlg1600 (0.1 cM of interval). This QTL could account for 50.0% of phenotypic variation, and could decrease 27.9% of
disease index. 相似文献
11.
Identification of QTLs controlling quantitative characters in rice using RFLP markers 总被引:14,自引:0,他引:14
Summary Segregation of plant height (PH), tiller number (TN), panicle number (PN), average panicle length per plant (PL), average primary branch number per panicle per plant (PBN) and 1000 grain weight (1000G) were specific in an F2 population derived from a cross of Palawan, a tall Javanica variety, and IR42, an Indica semidwarf variety. One hundred and four informative RFLP markers covering all 12 chromosomes were used for detecting putative QTLs controlling the traits. Orthogonal contrasts and interval mapping analysis were used for the analysis. QTL detected for PH on the region of chromosome 1, where semidwarfing gene sd-1 locus is located, seems to be a multiple allelic locus. An additional QTL for PH was identified on chromosome 2. Two QTLs for TN were detected on chromosomes 4 and 12. The QTL on chromosome 4 seemed also to govern the variation in PN. Four QTLs were found for the other traits, two of them for PL were located on chromosomes 6 and 2, one for PBN on chromosome 6 and the other for 1000G on chromosome 1. Additive gene actions were found to be predominant, except one QTL for PH and one QTL for PL, but partial or incomplete dominance also existed for the QTLs detected. 相似文献
12.
Qun Wan Zhengsheng Zhang Meichun Hu Li Chen Dajun Liu Xiao Chen Wei Wang Jing Zheng 《Euphytica》2007,158(1-2):241-247
A genetic linkage map of chromosome 6 was constructed by using 270 recombinant inbred lines originated from an upland cotton
cross (Yumian 1 × T586) F2 population. The genetic map included one morphological (T1) and 18 SSR loci, covering 96.2 cM with an average distance of 5.34 cM between two markers. Based on composite interval mapping
(CIM), QTL(s) affecting lint percentage, fiber length, fiber length uniformity, fiber strength and spiny bollworm resistance
(Earias spp.) were identified in the t1 locus region on chromosome 6. The allele(s) originating from T586 of QTLs controlling lint percentage increased the trait
phenotypic value while the alleles originating from Yumian 1 of QTLs affecting fiber length, fiber length uniformity, fiber
strength and spiny bollworm resistance increased the trait phenotypic value. 相似文献
13.
Summary
Septoria glume blotch, caused by Stagonospora nodorum, is an important disease of wheat (Triticum aestivum). Separate genetic mechanisms were found to control flag leaf and spike resistance. Genes for resistance to S. nodorum were located on different chromosomes in the few wheat cultivars studied. These studies only partially agree on the chromosome locations of gene in wheat for resistance to S. nodorum, and chromosomal arm locations of such genes are not known. The objectives of this study were to determine the chromosome and chromosomal arm locations of genes that significantly influence resistance to S. nodorum in wheat cultivar Cotipora. Monosomic analysis showed that flag leaf resistance was controlled by genes on chromosomes 3A, 4A, and 3B whereas the spike resistance was controlled by genes on chromosomes 3A, 4A, 7A, and 3B (P=0.01). Additionally, genes on chromosomes 6B and 5A influenced the susceptibility of the flag leaf and spike reactions, respectively (P=0.01). Telocentric analysis showed that genes on both arms of chromosome 3A, and the long arms of chromosomes 4A and 3B were involved in the flag leaf resistance whereas genes on both arms of chromosome 4A, the short arm of chromosome 3A, and the long arm of chromosome 3B conferred spike resistance. 相似文献
14.
Richard Finkers Yuling Bai Petra van den Berg Ralph van Berloo Fien Meijer-Dekens Arjen ten Have Jan van Kan Pim Lindhout Adriaan W. van Heusden 《Euphytica》2008,159(1-2):83-92
Tomato (Solanum lycopersicum) is susceptible to gray mold (Botrytis cinerea). Quantitative resistance to B. cinerea was previously identified in a wild relative, S. neorickii G1.1601. The 122 F3 families derived from a cross between the susceptible S. lycopersicum cv. Moneymaker and the partially resistant S. neorickii G1.1601 were tested for susceptibility to B. cinerea using a stem bioassay. Three putative quantitative trait loci (pQTL) were detected: pQTL3 and pQTL9 reducing lesion growth
(LG) and pQTL4 reducing disease incidence (DI). For each pQTL, a putative homologous locus was identified recently in another
wild tomato relative, S. habrochaites LYC4. pQTL3 was confirmed by assessing disease resistance in BC3S1 and BC3S2 progenies of S. neorickii G1.1601. pQTL4 was not statistically confirmed but the presence of the S. neorickii resistance allele reduced DI in all three tested populations. The reduction in LG of pQTL9 was not confirmed but rather,
this locus conferred a reduced DI, similar to observations in the QTL study using S. habrochaites. The results are discussed in relation to other disease resistance loci identified in studies with other wild tomato relatives. 相似文献
15.
‘Conrad’, a soybean cultivar tolerant to Phytophthora root rot (PRR), and ‘OX760-6-1’, a breeding line with low tolerance
to PRR, were crossed. F2 derived recombinant inbred lines were advanced to F6 to generate a population through single-seed descent. This population was used to identify quantitative trait loci (QTLs)
influencing PRR tolerance in ‘Conrad’. A total of 99 simple sequence repeat (SSR), or microsatellite, markers that were polymorphic
and clearly segregated in the F6 mapping population were used for QTL detection. Based on the data of PRR in the field at two planting locations, Woodslee
and Weaver, for the years 2000 and 2001, one putative QTL, designated as Qsatt414-596, was detected using MapMaker/QTL. Qsatt414-596
was flanked by two SSR markers from the linkage group MLG J, Satt414 and Satt596. Satt414 and Satt596 were also detected to
be significantly (P < 0.005) associated with PRR using the SAS GLM procedure and were estimated to explain 13.7% and 21.5% of the total phenotypic
variance, respectively. 相似文献
16.
Identification of QTLs controlling rice drought tolerance at seedling stage in hydroponic culture 总被引:1,自引:0,他引:1
‘Drought avoidance’ and ‘drought tolerance’ are two mechanisms by which plants adapt under water stress. These mechanisms
are difficult to evaluate separately in field experiments. Using hydroponic culture, we studied the genetic control of drought
tolerance in rice (Oryza sativa L.) without the effect of drought avoidance. A backcross inbred population of ‘Akihikari’ (lowland cultivar) × ‘IRAT109’
(upland cultivar) with 106 lines was cultured with (stressed condition) and without (non-stressed condition) polyethylene
glycol (PEG) at seedling stage. The relative growth rate (RGR), specific water use (SWU), and water use efficiency (WUE) showed
significant genotype × environment interactions with or without PEG, indicating that each line responded differently to water
stress. A quantitative trait locus (QTL) analysis revealed that these interactions were QTL specific. A total of three QTLs
on chromosomes 2, 4, and 7 were detected for RGR. The QTL on chromosome 7 had a constant effect across environments, while
the QTL on chromosome 4 had an effect only under non-stressed condition and that on chromosome 2 only under stressed condition.
The stress-specific QTL on chromosome 2 was not co-located with any QTLs for root system depth previously reported from the
same mapping population. However, this QTL was co-located with a stress-specific QTL for SWU, suggesting that the control
of transpiration was relevant to dry matter production under drought. We concluded that PEG-treated hydroponic culture is
very effective for use in genetic analyses of drought tolerance at seedling stage. 相似文献
17.
Summary Fifty-four land races of dry beans (Phaseolus vulgaris), indigenous to areas of Brazil where anthracnose (caused by Colletotrichum lindemuthianum) is a common problem, were evaluated in field nurseries for partial resistance to race Brazilian 1 (B1) of C. lindemuthianum using symptom severity classes (SSC) from 0 to 6. Plants were selected if symptoms were present and the SSC was less than the 95% confidence interval of the mean SSC of the susceptible cultivar Carioca. S1 progeny from selected plants were evaluated in air-conditioned chambers for partial resistance to races B1, delta, and kappa of C. lindemuthianum. Of 246 S1 families evaluated, 145 families were partially resistant to one or two of the races [symptoms present, but S1 family mean significantly (p<0.05) less than the mean of Carioca] and susceptible to the third. Six families were partially resistant to all three races. The remaining families were either susceptible or segregated for reaction to race B1. Partial resistance to C. lindemuthianum showed race specificity in the air-conditioned chambers and field nurseries. 相似文献
18.
Zhi-Hong Zhang Ping Li Ling-Xia Wang Chang-Jun Tan Zhong-Li Hu Ying-Guo Zhu Li-Huang Zhu 《Euphytica》2002,128(2):279-284
The number of vascular bundles in peduncle and the ratio of vascular bundles to primary rachis branches (V/R ratio)distinguishable
between indica andjaponica, are the traits associated with the processes of differentiation between indica and japonica inrice (Oryza sativa L.). In this paper a doubled-haploid population derived from the F1 hybrid of a cross between anindica cultivar and a japonicacultivar was used to map quantitative trait loci(QTLs) controlling numbers of vascular bundles in peduncle, primary rachis
branches and the V/R ratio. For vascular bundles, three QTLs were detected and they collectively explained 58.8% of the total
variation. Among them, the QTLqVB-8 with the largest effect,located on chromosome 8, individually accounted for 31.1% of the total variation. Two QTLs controlling
primary rachis branches, located on chromosome 8and 10 respectively, were identified and they individually explained 10.5%
and18.0% of the total variation respectively. Three QTLs for the V/R ratio, mapped on chromosome 1, 2 and 8, respectively,jointly
explained 61.3% of the total variation. Of the three QTLs, the QTL qV/R-1 with the largest additive effect,explained 25.3% of the total variation,was located on chromosome 1 and found to be closely
linked to the gene sh-2, a major gene underlying grain-shattering ability. In addition, four and two pairs of significant epistatic QTLs were detected
for vascular bundles and the V/R ratio,respectively, but none for rachis branches. Our results suggested that the numbers
of vascular bundles and primary rachis branches were independently controlled by different polygenic systems, but the two
polygenic systems shared a fraction of quantitative trait loci. The present study also demonstrated that the chromosome region
carrying the QTL qV/R-1 for the V/R ratio and the gene sh-2 might play an important role in the processes ofindica-japonica differentiation in rice (Oryza sativa L.).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
19.
Bhoja R. Basnet Karl D. Glover Amir M. H. Ibrahim Yang Yen Shiaoman Chao 《Euphytica》2012,186(1):91-101
Much effort has been invested in identifying molecular markers in wheat (Triticum aestivum L.) linked to quantitative trait loci (QTL) that confer resistance to Fusarium head blight (FHB) caused by Fusarium graminearum Schwabe [teleomorph Gibberella zeae (Schwein) Petch]. Even after several generations of crossing and selection by many wheat breeding programs, resistance of the Chinese spring wheat cultivar ‘Sumai 3’ (PI 481542) remains among the most effective. It therefore seems that undocumented resistance QTL present in Sumai 3 were not detected in various mapping studies. Using an extremely susceptible Tibetan landrace (‘Y1193-6’; unknown pedigree) in the creation of a mapping population with Sumai 3, the objective of this research was to identify undocumented resistance QTL in Sumai 3. This was accomplished through collecting disease index (DI) and Fusarium damaged kernel (FDK) phenotypic values along with 305 Diversity Array Technology (DArT) and 52 Simple Sequence Repeat (SSR) marker genotypes on 160 F2:6 recombinant inbred lines (RILs). Disease response evaluations were based on four (two greenhouse and two field) experiments where spray inoculation methods were used. Three QTL were identified on chromosome arms 3BS, 6BL and 2DS explaining 26.1, 10.7 and 18.9% of the phenotypic variation for DI, respectively. The same QTL were also significantly associated with reduced FDK scores and explained 28.0, 11.0 and 23.0% of phenotypic variation. Lines within the mapping population were placed in eight categories with respect to their various QTL combinations. Lines with no QTL were the most susceptible, whereas those with the Sumai 3-derived 3BS and 6BL QTL combined with the 2DS QTL from Y1193-6 were the most resistant. Though the 3BS and 6BL QTL are well-documented, the 2DS resistance QTL, which was contributed by the susceptible parent, confers increased susceptibility when derived from Sumai 3. In this study no new FHB QTL from Sumai 3 was discovered, but results suggest that Sumai 3 contains a QTL for susceptibility on chromosome arm 2DS. Selection against this QTL may potentially increase resistance levels among Sumai 3-derived populations. 相似文献
20.
Summary F1 hybrids of triazine resistant Brassica napus and triazine susceptible B. oleracea were morphologically intermediate to the parent species. Of 49 hybrids examined, 44 had 28 chromosomes, two had 37, one had 38 and two had 56. The 38-chromosome plant was thought to be a matromorph, the others, A1C1C (28), A1C1CC (37) or A1A1C1C1CC (56) type hybrids. Pollen stainability averaged 9.0% in the sesquidiploid, 32.0% in the tetraploids and 89.5% in the hexaploids. All the interspecific hybrids were resistant to 1.0×10-4 mol L-1 atrazine. The sesquidiploid hybrids produced gametes with chromosome numbers ranging from 9 to 17 and the tetraploid hybrid gametes had chromosome numbers from 15 to 22. Most hybrids produced self-seed. The partial fertility of these hybrids may permit their backcrossing to one or both parents. 相似文献