共查询到20条相似文献,搜索用时 359 毫秒
1.
Molecular mapping and detection of the yellow rust resistance gene Yr26 in wheat transferred from Triticum turgidum L. using microsatellite markers 总被引:15,自引:0,他引:15
Jianxin Ma Ronghua Zhou Yushen Dong Lanfen Wang Xiaoming Wang Jizeng Jia 《Euphytica》2001,120(2):219-226
Yellow rust (stripe rust), caused by Puccinia striiformis Westend f. sp. tritici, is one of the most devastating diseases of wheat throughout the world. Wheat-Haynaldia villosa 6AL.6VS translocation lines R43, R55, R64 and R77, derived from the cross of three species, carry resistance to both yellow
rust and powdery mildew. An F2 population was established by crossing R55 with the susceptible cultivar Yumai 18. The yellow rust resistance in R55 was
controlled by a single dominant gene, which segregated independently of the powdery mildew resistance gene Pm21 located in the chromosome 6VS segment, indicating that the yellow rust resistance gene and Pm21 are unlikely to be carried by the same alien segment. This yellow rust resistance gene was considered to beYr26, originally thought to be also located in chromosome arm 6VS. Bulked Segregation Analysis and microsatellite primer screens
of the population F2 of Yumai 18 × R55 identified three chromosome 1B microsatellite locus markers, Xgwm11, Xgwm18 and Xgwm413, closely linked to Yr26. Yr26 was placed 1.9 cM distal of Xgwm11/Xgwml8, which in turn were 3.2 cM from Xgwm413. The respective LOD values were 21 and 36.5. Therefore, Yr26 was located in the short arm of chromosome 1B. The origin and distribution of Yr26 was investigated by pedigree, inheritance of resistance and molecular marker analysis. The results indicated that Yr26 came from Triticum turgidum L. Three other 6AL.6VS translocation lines, R43, R64 and R77, also carried Yr26. These PCR-based microsatellite markers were shown to be very effective for the detection of the Yr26 gene in segregating populations and therefore can be applied in wheat breeding.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
Emily B. Johnson Vamsi J. Nalam Robert S. Zemetra Oscar Riera-Lizarazu 《Euphytica》2008,163(2):193-201
The spikes of club wheat are significantly more compact than spikes of common wheat due to the action of the dominant allele
of the compactum (C) locus. Little is known about the location of C on chromosome 2D and the relationship between C and to other spike-compacting genes. Thus, a study was undertaken to place C on linkage maps and a chromosome deletion bin, and to assess its relatedness to the spike compacting genes zeocriton (Zeo) from barley and soft glume (Sog) from T. monococcum. Genetic mapping was based on recombinant inbred lines (RILs) from a cross between the cultivars Coda (club) and Brundage
(common) and F2 progeny from a cross between the club wheat Corrigin and a chromosome 2D substitution line [Chinese Spring (Ae. tauschii 2D)]. The C locus was flanked by Xwmc144 and Xwmc18 in the RIL population and it was completely linked to Xcfd116, Xgwm358 and Xcfd17 in the F2 population. C could not be unambiguously placed to a chromosome bin because markers that were completely linked to C or flanked this locus were localized to chromosome bins on either side of the centromere (C-2DS1 and C-2DL3). Since C has been cytogenetically mapped to the long arm of chromosome 2D, we suspect C is located in bin C-2DL3. Comparative mapping suggested that C and Sog were present in homoeologous regions on chromosomes 2D and 2Am, respectively. On the other hand, C and Zeo, on chromosome 2H, did not appear to be orthologous. 相似文献
3.
Summary
Aegilops umbellulata acc. Y39 and Triticum carthlicum acc. PS5, immune to many powdery mildew isolates, were crossed to make an amphidiploid line Am9. The powdery mildew resistance of Am9 was transferred to common wheat cultivar Laizhou953 by crossing and backcrossing. In this study, the origin of powdery mildew resistance in a BC3F4:5 population derived from a cross of Am9 and Laizhou953 was identified. Microsatellite markers analysis showed that markers Xgwm257, Xgwm296, and Xgwm319, co-segregated with the powdery mildew resistance, whereas markers Xgwm210, Xgwm388/140, Xgwm388/170 and Xgwm526 were related to susceptibility and linked to resistance in repulsion. Of three markers related to resistance, Xgwm257 and Xgwm319 were codominant, whereas Xgwm296 was dominant. All three markers were Ae. umbellulata-specific indicating that resistance in the test population originated from Ae. umbellulata acc. Y39. The chromosome location and mapping of these linked microsatellite markers, the chromosome numbers of derived BC3F4:6 families, and chromosome pairing in F1 plants from a cross of a homozygous resistant BC3F4:5 plant and Laizhou953, showed that wheat chromosome 2B was substituted by Ae. umbellulata chromosome 2U. This is the first gene conferring powdery mildew resistance transferred to wheat from Ae. umbellulata, and it should be a novel resistance gene to powdery mildew. It was temporarily designated PmY39.The first two authors made equal contributions 相似文献
4.
Triticum monococcum L. (2n = 2x = 14, AmAm genome) is one of the most ancient of the domesticated crops in the Middle East, but it is not the ancestor of the A genome
of durum wheat (T. durum Desf. 2n = 4x = 28, genomes BBAA) and bread wheat (T. aestivum L., 2n = 6x = 42, genomes BBAADD). It has been suggested that some differentiation has occurred between the Am and A genomes. The chlorina mutants at the cn-A1 locus located on chromosome 7AL have been described in T. aestivum L. and T. durum, and a chlorina mutant has been found in T. monococcum. The aims of our study were to establish linkage maps for chlorina mutant genes on chromosome 7A of T. aestivum and T. durum and chromosome 7Am of T. monococcum and to discuss the differentiation that has occurred between the A and Am genomes. The chlorina mutant gene was found to be linked with Xhbg234 (8.0 cM) and Xgwm282 (4.3 cM) in F2 plants of T. aestivum ANK-32A/T. petropavlovskyi k54716, and with Xbarc192 (19.5 cM) and Xgwm282 (12.0 cM) in F2 plants of T. durum ANW5A-7A/T. carthlicum #521. Both the hexaploid and tetraploid wheats contained a common marker, Xgwm282. In F2 lines of T. monococcum KT 3-21/T. sinskajae, the cn-A1 locus was bracketed by Xgwm748 (25.7 cM) and Xhbg412 (30.8 cM) on chromosome 7AmL. The distal markers, Xhbg412, Xgwm282, and Xgwm332, were tightly linked in T. aestivum and T. durum. The common marker Xhbg412 indicated that the chlorina mutant genes are located on chromosome 7AL and that they are homoeologous mutations. 相似文献
5.
Conxita Royo Fanny Álvaro Vanessa Martos Abdelhamid Ramdani Julio Isidro Dolors Villegas Luis F. García del Moral 《Euphytica》2007,155(1-2):259-270
Twelve field experiments comparing 24 durum wheat varieties from three periods—old (<1945), intermediate (1950–1985) and modern
(1988–2000)—were carried out in order to ascertain the advances made in durum wheat yield components and related traits in
Italian and Spanish germplasm. Grain yield improvements were based on linear increases in the number of grains per m2 and harvest index, while grain weight and biomass remained unchanged. Yield per plant increased at a rate of 0.36 and 0.44%
y−1 and the number of grains per m2 improved by 39% and 55% in Italian and Spanish varieties, respectively. The mean rate of increase in the number of grains
per m2 was 0.55% y−1. Plants per m2, spikes per plant and grains per spike contributed 20%, 29% and 51%, respectively, to the increase in the number of grains
per m2. The enhance of the number of grains per m2 was due to the greater grain set in the modern varieties, since the number of spikelets per spike remained unchanged. Harvest
index increased overall by 0.48% y−1 (0.40 and 0.53% y−1 in Italian and Spanish varieties, respectively). Plant height was the trait that suffered the most dramatic changes (it decreased
at a rate of −0.81% y−1, with little difference between the varieties of the two countries), as consequence of the presence of the Rht-B1 dwarfing gene. Harvest index and plant height, which were the traits that most contributed to discriminating between periods,
remained unchanged from 1980 to 2000. The higher rates of improvement in Spain are discussed in the context of the contrasting
strategies followed to improve durum wheat yield in the two countries. 相似文献
6.
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
7.
Xiaoling Ji Chaojie Xie Zhongfu Ni Tsomin Yang Eviatar Nevo Tzion Fahima Zhiyong Liu Qixin Sun 《Euphytica》2008,159(3):385-390
Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a devastating disease of wheat (Triticum aestivum) in China and worldwide, causing severe yield losses annually. Wild emmer (T. dicoccoides) accession IW72 collected from Israel is resistant to powdery mildew at the seedling and adult stages. Genetic analysis indicated
that the resistance was controlled by a single dominant gene, temporarily designated MlIW72. The F2 population and F3 families derived from a hybrid between IW72 and susceptible durum wheat line Mo75 were used for molecular mapping of the
resistance gene. MlIW72 was linked with SSR loci Xgwm344, Xcfa2040, Xcfa2240, Xcfa2257 and Xwmc525 on the long arm of chromosome 7A. In addition, two STS markers, MAG2185 (derived from RFLP marker PSR680) and MAG1759 (developed
from EST CD452874), were mapped close to MlIW72. All these markers were physically located in the terminal bin 0.86–1.00 of 7AL. The chromosome location and genetic mapping
results suggested that the powdery mildew resistance gene identified in wild emmer accession IW72 might be a new allele at
the Pm1 locus or a new locus closely linked to Pm1. 相似文献
8.
Liguleless phenotypes of wheat lack ligule and auricle structures on all leaves of the plant. Two recessive genes principally control the liguleless character in tetraploid wheat. The F2 progenies of k17769 (liguleless mutant)/Triticum dicoccoides and k17769/T. dicoccum segregated in a 15:1 ratio, whereas the F2 progenies of k17769/T. durum and k17769/T. turgidum segregated in a 3:1 ratio. A new gene, lg3, was found on chromosome 2A. Segregation of F2 progenies between k17769 and chromosome substitution lines for homoeologous group 2 chromosomes suggested that the liguleless genotype had occurred by mutation at the lg3 locus on chromosome 2A, and then by mutation at the lg1 locus on chromosome 2B, in the process of domestication of tetraploid wheat. The gene (lg1) was linked to Tc2 (11.9 cM), which determines phenol colour reaction of kernels, on the long arm of chromosome 2B. The distance of lg1 to the centromere was found to be 60.4 cM, and microsatellite mapping established the gene order, centromere – Xgwm382 – Xgwm619 – Tc2 – lg1 on the long arm of chromosome 2B. 相似文献
9.
The inheritance of the leaf pubescence character of a Chinese local wheat cultivar ‘Hon-mang-mai’ was investigated by monosomic
and telosomic analyses. Leaf pubescence was evaluated by observation of the adaxial side of the penultimate leaf of adult
plants. F1 hybrids of ‘Hong-mang-mai’ with a non-pubescent cultivar ‘Chinese Spring’ had leaf pubescence, but its density was about
a half of that of ‘Hong-mang-mai’. In the F2 generation, the segregation ratio of pubescent to non-pubescent plants fitted a ratio of 3: 1, suggesting that leaf pubescence
was controlled by one dominant gene. Monosomic analysis revealed that the gene for pubescence is located on chromosome 7B.
Telosomic analysis showed that the gene is located on the short arm of chromosome 7B with a distance of 14.3%from the centromere.
This gene is not allelic with the previously reported hairy leaf gene Hl on chromosome 4B, and therefore, is designated Hl2, hairy leaf 2.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
Telosomic mapping of the homoeologous genes for the long glume phenotype in tetraploid wheat 总被引:1,自引:0,他引:1
Triticum turgidum ssp. polonicum and T. ispahanicum were characterized by the long glume phenotype. P
1 gene determines the long glume phenotype of T. polonicum, and locates on chromosome 7A. T. ispahanicum has shorter glume than T. polonicum and the long glumephenotype is determined by P
2 gene located on chromosome 7B. In the present study, aneuploid stocks of `Langdon' durum wheat were used to map the genes, P
1 and P
2. P
1 located on the long arms of chromosome 7A and its map distances from the centromere was 14.5 cM. On chromosome 7B, four loci located as cc (chocolate black chaff) – Pc (purple culm) – centromere – P
2 – cn-BI (chlorina). P
2 located on the long arms of chromosome 7B and its map distances from the centromere was 11.7 cM. It was suggested that a paralogous gene set conditions long glume phenotype in the homoeologous group 7 chromosomes. The P
1 and P
2 genes may be useful as genetic markers in tetraploid wheat. 相似文献
11.
I. Leonova E. Pestsova E. Salina T. Efremova M. Röder A. Börner G. Fischbeck 《Plant Breeding》2003,122(3):209-212
An F2 population segregating for the dominant gene Vrn‐B1 was developed from the cross of the substitution line ‘Diamant/'Miro‐novskaya 808 5A’ and the winter wheat cultivar ‘Bezostaya 1′. Microsatellite markers (Xgwm and Xbarc) with known map locations on chromosome 5B of common wheat were used for mapping the gene Vrn‐B1. Polymorphism between parental varieties was observed for 28 out of 34 microsatellite markers (82%). Applying the quantitative trait loci mapping approach, the target gene was mapped on the long arm of chromosome 5B, closely linked to Xgwm408. The map position of Vrn‐B1 suggests that the gene is homoeologous to other vernalization response genes located on the homoeologous group 5 chromosomes of wheat, rye and barley. 相似文献
12.
Summary Several near-isogenic lines of durum wheat cv. LD222 have been developed. These include a near-isogenic line carrying gene P and designated P-LD222. The P gene from Triticum polonicum determines a long empty outer glume. The objective of this study was to determine the inheritance and chromosomal location of the P gene. To determine the inheritance, P-LD222 was crossed to two chlorina mutants and to a near-isogenic line for the purple culm trait, Pc-LD222. Linkage of the P gene with the mutated gene in chlorina mutant CDd6 indicated that the P gene was located on chromosome 7A. P-LD222 was also crossed with durum cultivar Langdon (LDN) and the LDN D genome substitution lines, LDN 7D(7A) and LDN 7D(7B). Segregation for the long glume trait in the F2 of LDN/P-LD222 and LDN 7D(7B)/P-LD222 was normal (3:1) and indicated P gene was not on chromosome 7B. Significant deviation from a 3:1 in the F2 of LDN 7D(7A)/P-LD222 confirmed the location of P on chromosome 7A, as indicated by the linkage analysis. 相似文献
13.
M. Golabadi A. Arzani S. A. M. Mirmohammadi Maibody B. E. Sayed Tabatabaei S. A. Mohammadi 《Euphytica》2011,177(2):207-221
Grain yield and yield components are the main important traits involved in durum wheat (Triticum turgidum L.) improvement programs. The purpose of this research was to identify quantitative trait loci (QTL) associated with yield
components such as 1000 grain weight (TGW), grain weight per spike (GWS), number of grains per spike (GNS), spike number per
m2 (SN), spike weight (SW), spike harvest index (SHI) and harvest index (HI) using microsatellite markers. Populations of F3 and F4 lines derived from 151 F2 individuals developed from a cross between Oste-Gata, a drought tolerant, and Massara-1, a drought susceptible durum wheat
genotypes, were used. The populations were evaluated under four environmental conditions including two irrigation regimes
of drought stress at terminal growth stages and normal field conditions in two growing seasons. Two hundred microsatellite
markers reported for A and B genomes of bread wheat were used for parental polymorphism analysis and 30 polymorphic markers
were applied to genotype 151 F2:3 families. QTL analysis was performed using genome-wide single marker regression analysis (SMA) and composite interval mapping
(CIM). The results of SMA revealed that about 20% of the phenotypic variation of harvest index and TGW could be explained
by Xcfd22-7B and Xcfa2114-6A markers in different environmental conditions. Similarly, Xgwm181-3B, Xwmc405-7B and Xgwm148-3B and marker Xwmc166-7B were found to be associated with SHI and GWS, respectively. A total of 20 minor and major QTL were detected; five for
TGW, two for GWS, two for GNS, three for SN, five for HI, two for SHI and one for SW. The mapped QTL associated with ten markers.
Moreover, some of these QTL were prominent and stable under drought stress and non drought stress environments and explained
up to 49.5% of the phenotypic variation. 相似文献
14.
Identification and molecular mapping of a leaf rust resistance gene in spelt wheat landrace Altgold 总被引:2,自引:0,他引:2
Yanjie Wang Huiru Peng Gang Liu Chaojie Xie Zhongfu Ni Tsomin Yang Zhiyong Liu Qixin Sun 《Euphytica》2010,174(3):371-375
Leaf rust, caused by Puccinia triticina, is an important disease for wheat production, both in China and worldwide. In laboratory studies spelt wheat (Triticum aestivum ssp. spelta) landrace Altgold was resistant to P. triticina races THT and PHT and genetic analysis indicated that it possessed a dominant leaf rust resistance gene, temporarily designated
LrAlt. F6 recombinant inbred lines (RILs) derived from a cross with the susceptible common wheat cultivar Nongda 3338 were used to
map LrAlt with SSR markers. The resistance gene was distal to SSR loci Xbarc212, Xwmc382, Xgwm636, and Xwmc407 on the short arm of chromosome 2A. The closest markers Xbarc212 and Xwmc382 which co-segregated were 1.8 cM away from LrAlt. The relationships of LrAlt and other wheat leaf rust resistance genes located on the short arm of chromosome 2A were discussed, suggesting that LrAlt might be a new leaf rust resistance gene. 相似文献
15.
The introduction into bread wheat of a major gene for resistance to powdery mildew from wild emmer wheat 总被引:19,自引:0,他引:19
Summary A new source of resistance to wheat powdery mildew caused by Erysiphe graminis has been transferred to hexaploid bread wheat, Triticum aestivum, from the wild tetraploid wheat, Triticum dicoccoides. The donor was crossed to bread wheat and the pentaploid progeny was then self-pollinated. Plants having a near stable hexaploid chromosome complement were selected in the F3 progeny and topcrossing and backcrossing of these to a second wheat cultivar to improve the phenotype was undertaken. Monosomic analysis of early backcross lines showed the transferred gene to be located on chromosome 4A. The gene has been designated Pm16. 相似文献
16.
Molecular characterization of a novel powdery mildew resistance gene Pm30 in wheat originating from wild emmer 总被引:1,自引:0,他引:1
Powdery mildew caused by Erysiphe graminis f. sp. tritici is one of the most important wheat diseases in many regions of theworld. A powdery mildew resistance gene, originating from wild emmerwheat (Triticum dicoccoides) accession `C20', from Rosh Pinna, Israel,was successfully transferred to hexaploid wheat through crossing andbackcrossing. Genetic analysis indicated that a single dominant genecontrols the powdery mildew resistance at the seedling stage. SegregatingBC1F2 progenies of the cross 87-1/C20//2*8866 wereused for bulked segregant analysis (BSA). The PCR approach was used togenerate polymorphic DNA fragments between the resistant and susceptibleDNA pools by use of 10-mer random primers, STS primers, and wheatmicrosatellite primers. Three markers, Xgwm159/430,Xgwm159/460, and Xgwm159/500, were found to be linked tothe resistance gene. After evaluating the polymorphic markers in twosegregating populations, the distance between the markers and the mildewresistance gene was estimated to be 5–6 cM. By means of ChineseSpring nullisomic-tetrasomics and ditelosomics, the polymorphic markersand the resistance gene were assigned to chromosome arm 5BS and werephysically mapped on the gene rich regions of fragment length (FL) 0.41–0.43 by Chinese Spring deletion lines. As no powdery mildew resistancegene has been reported on chromosome arm 5BS, the mildew resistancegene originating from C20 should be a new gene and is designated Pm30. 相似文献
17.
A novel photoperiod response gene, designated Ppd-B2, was mapped to wheat chromosome arm 7BS, using a set of lines carrying various segments of 7BS from the early flowering breeding
line ‘F26-70 7B’ in a background of the variety ‘Favorit’. The gene was 4.4 cM distal of the microsatellite locus Xgwm0537 and 20.7 cM proximal to Xgwm0255. In contrast to the well-characterized Ppd-1 genes, which require short days for expression, Ppd-B2 was detected when plants were exposed to a long photoperiod. The accelerated flowering produced by Ppd-B2 was correlated with increased grain protein content. 相似文献
18.
Understanding the genetic basis of tolerance to high temperature is important for improving the productivity of wheat (Triticum aestivum L.) in regions where the stress occurs. The objective of this study was to estimate inheritance of heat tolerance and the
minimum number of genes for the trait in bread wheat by combining quantitative genetic estimates and molecular marker analyses.
Two cultivars, Ventnor (heat-tolerant) and Karl92 (heat-susceptible), were crossed to produce F1, F2, and F3populations, and their grain-filling duration (GFD) at 30/25 °C 16/8 h day/night was determined as a measure of heat tolerance. Distribution of GFD in the F1 and F2 populations followed the normal model (χ2, p > 0.10). A minimum of 1.4 genes with both additive and dominance effects, broad-sense heritability of 80%, and realized heritability
of 96%for GFD were determined from F2 and F3 populations. Products from 59primer pairs among 232 simple sequence repeat (SSR) pairs were polymorphic between the parents.
Two markers, Xgwm11 andXgwm293, were linked to GFD by quantitative trait loci (QTL) analysis of the F2 population. The Xgwm11-linked QTL had only additive gene action and contributed 11% to the total phenotypic variation in GFD in the F2population, whereas the Xgwm293-linked QTL had both additive and dominance action and contributed 12% to the total variation in GFD. The results demonstrated
that heat tolerance of common wheat is controlled by multiple genes and suggested that marker-assisted selection with microsatellite
primers might be useful for developing improved cultivars.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
19.
Recently a major gene determining non-specific adult plant disease resistance against stripe rust (Puccinia striiformis) designated Yrns-B1 was mapped in wheat Triticum aestivum L. by using a cross between ‘Lgst. 79-74’ (resistant) and ‘Winzi’ (susceptible). Linkage to five Gatersleben wheat microsatellite
(GWM) markers was discovered, previously mapped on chromosome arm 3BS. In the present study this map was improved by the incorporation
of four additional GWM markers. QTL-analysis revealed high LOD values for the resistance at all nine loci, whereas the largest
LOD (20.76) was found for the newly mapped marker Xgwm1329.
Microsatellite analysis and resistance tests of a collection of old German/UK wheat varieties, including probable ancestors
of ‘Lgst.79-74’ were carried out. A high coincidence of non-specific adult plant disease resistance against stripe rust and
the presence of ‘Lgst. 79-74’ allele (117 bp) of the marker Xgwm533 was observed among the varieties tested. Linkage during the inheritance of both the resistance and the 117 bp allele of Xgwm533 was demonstrated. The probable origin of Yrns-B1 is discussed. Carriers of this resistance gene were grown on large areas since more than 100 years. To estimate the capability
of Xgwm533 as a diagnostic marker for non-specific adult plant disease resistance against stripe rust, microsatellite analysis and resistance
tests of a collection of Russian spring wheat varieties were performed. The 117 bp allele of Xgwm533 was found in about 35% of the Russian cultivars analysed, however, none of them possessed the expected disease resistance.
Thus, the utilisation of Xgwm533 as diagnostic marker seems to be restricted to certain genepools. 相似文献
20.
`Langdon' (LDN), a durum wheat (Triticum turgidum L. var. durum) cultivar, and a set of chromosome substitution lines of Langdon, where A or B genome chromosome were replaced with a homologous
chromosome of wild emmer wheat, T. turgidum ssp. dicoccoides (DIC), were used to assess the effect of the specific chromosome on seed dormancy in tetraploid wheat. The LDN(DIC 3A) and
LDN (DIC 313) lines showed significantly lower seed germination than Langdon. It appears that LDN(DIC 3A) and LDN(DIC 3B)
have red grain whose allele were designated as R-A1b and R-B1b, respectively and the rachises of LDN(DIC 3A) and LDN(DIC 3B) were fragile. The alleles for brittle rachis were designated
as Br
2 for LDN(DIC 3A) and Br
3 for LDN(DIC 3B). From the F2 of the crosses, Langdon/LDN(DIC 3A) and Langdon/LDN(DIC 3B), Br
2 was located approximately 44.2 cM from the R-A1b locus and Br
3 approximately 47.0 cM from the R-B1b locus, respectively. Recombinant inbred chromosomal lines for 3A and 3B were used to assess (1) the linkage relationship
between grain colour and fragile rachis, and (2) the effect of grain colour on germination. Estimated distance between R-B1b – Br
2 was 39.6 cM. For the 3A population, germination percentage of both colour groups was 12.4% for the red grain group and 68.6%
for the amber group, respectively. For the 3B population, germination percentage of the red group was 7.3% and that of the
amber group was 82.1%. For both populations, differences were statistical significant by t-tests. We considered that seed dormancy of T. turgidum ssp. dicoccoides was dependent on grain colour. It raised the possibility that brittle rachis is due to a paralogous gene set on homoeologous
group 3 chromosomes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献