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1.
Sheng Chen Matthew N. Nelson Anne-Marie Chèvre Eric Jenczewski Zaiyun Li Annaliese S. Mason 《植物科学评论》2011,30(6):524-547
We introduce and review Brassica crop improvement via trigenomic bridges. Six economically important Brassica species share three major genomes (A, B, and C), which are arranged in diploid (AA, BB, and CC) and allotetraploid (AABB, AACC, and BBCC) species in the classical triangle of U. Trigenomic bridges are Brassica interspecific hybrid plants that contain the three genomes in various combinations, either triploid (ABC), unbalanced tetraploid (e.g., AABC), pentaploid (e.g., AABCC) or hexaploid (AABBCC). Through trigenomic bridges, Brassica breeders can access all the genetic resources in the triangle of U for genetic improvement of existing species and development of new agricultural species. Each of the three Brassica genomes occurs in several species, where they are distinguished as subgenomes with a tag to identify the species of origin. For example, the A subgenome in B. juncea (2n = AABB) is denoted as Aj and the A subgenome in B. napus (2n = AACC) as An. Trigenomic bridges have been used to increase genetic diversity in allopolyploid Brassica crop species, such as a new-type B. napus with subgenomes from B. rapa (Ar) and B. carinata (Cc). Recently, trigenomic bridges from several sources have been crossed together as the ‘founders’ of a potentially new allohexaploid Brassica species (AABBCC). During meiosis in a trigenomic bridge, crossovers are expected to form between homologous chromosomes of related subgenomes (for example Ar and An), but cross-overs may also occur between non-homologous chromosomes (for example between A and C genome chromosomes). Irregular meiosis is a common feature of new polyploids, and any new allotetraploid or allohexaploid Brassica genotypes derived from a trigenomic bridge must achieve meiotic stability through a process of diploidisation. New sequencing technologies, at the genomic and epigenomic level, may reveal the genetic and molecular basis of diploidization, and accelerate selection of stable allotetraploids or allohexaploids. Armed with new genetic resources from trigenomic bridges, Brassica breeders will be able to improve yield and broaden adaptation of Brassica crops to meet human demands for food and biofuel, particularly in the face of abiotic constraints caused by climate change. 相似文献
2.
Intertribal somatic hybrids of Raphanus sativus (2n = 18, RR) and Brassica rapa spp. chinensis (2n = 20, AA) with the dye and medicinal plant Isatis indigotica (2n = 14, I I) were firstly obtained by polyethylene glycol-induced symmetric fusions of mesophyll protoplasts. One mature hybrid
with R. sativus established in field had intermediate morphology but was totally sterile. It had the expected chromosome number (2n = 32, RRI I) and parental chromosomes were distinguished by genomic in situ hybridization (GISH) analysis, and these chromosomes
were paired as 16 bivalents in pollen mother cells (PMCs) at diakinesis and mainly segregated equally as 16:16 at anaphase
I (A I), but the meiotic disturbance in second division was obvious. Five mature hybrids with B. rapa established in field were morphologically intermediate but showed some differences in phenotypic traits and fertility, two
were partially fertile. Cytological and GISH investigations revealed that these hybrids had 2n = 48 with AAIIII complement and their PMCs showed normal pairing of 24 bivalents and mainly equal segregation 24:24, but meiotic
abnormalities of lagging chromosomes and micronuclei appeared frequently during second divisions. AFLP analysis showed that
all of these hybrids had mainly the DNA banding pattern from the addition of two parents plus some alterations. Some hybrids
should be used for the genetic improvement of crops and the dye and medicinal plant. 相似文献
3.
Inter- and intra-genomic homology of the Brassica genomes: implications for their origin and evolution 总被引:7,自引:0,他引:7
M. J. Truco J. Hu J. Sadowski C. F. Quiros 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(8):1225-1233
In order to determine the homologous regions shared by the cultivated Brassica genomes, linkage maps of the diploid cultivated B. rapa (A genome, n = 10), B. nigra (B genome, n = 8) and B. oleracea (C genome, n = 9), were compared. We found intergenomic conserved regions but with extensitve reordering among the genomes. Eighteen linkage groups from all three species could be associated on the basis of homologous segments based on at least three common markers. Intragenomic homologous conservation was also observed for some of the chromosomes of the A, B and C genomes. A possible chromosome phylogenetic pathway based on an ancestral genome of at least five, and no more than seven chromosomes, was drawn from the chromosomal inter-relationships observed. These results demonstrate that extensive duplication and rearrangement have been involved in the formation of the Brassica genomes from a smaller ancestral genome. 相似文献
4.
Jeong-Hwan Mun Hee-Ju Yu Soomin Park Beom-Seok Park 《Molecular genetics and genomics : MGG》2009,282(6):617-631
Nucleotide-binding site (NBS)-encoding resistance genes are key plant disease-resistance genes and are abundant in plant genomes,
comprising up to 2% of all genes. The availability of genome sequences from several plant models enables the identification
and cloning of NBS-encoding genes from closely related species based on a comparative genomics approach. In this study, we
used the genome sequence of Brassica rapa to identify NBS-encoding genes in the Brassica genome. We identified 92 non-redundant NBS-encoding genes [30 CC-NBS-LRR (CNL) and 62 TIR-NBS-LRR (TNL) genes] in approximately
100 Mbp of B. rapa euchromatic genome sequence. Despite the fact that B. rapa has a significantly larger genome than Arabidopsis thaliana due to a recent whole genome triplication event after speciation, B. rapa contains relatively small number of NBS-encoding genes compared to A. thaliana, presumably because of deletion of redundant genes related to genome diploidization. Phylogenetic and evolutionary analyses
suggest that relatively higher relaxation of selective constraints on the TNL group after the old duplication event resulted
in greater accumulation of TNLs than CNLs in both Arabidopsis and Brassica genomes. Recent tandem duplication and ectopic deletion are likely to have played a role in the generation of novel Brassica lineage-specific resistance genes. 相似文献
5.
Kim JA Kim JS Hong JK Lee YH Choi BS Seol YJ Jeon CH 《Molecular genetics and genomics : MGG》2012,287(5):373-388
Circadian clocks regulate plant growth and development in response to environmental factors. In this function, clocks influence
the adaptation of species to changes in location or climate. Circadian-clock genes have been subject of intense study in models
such as Arabidopsis thaliana but the results may not necessarily reflect clock functions in species with polyploid genomes, such as Brassica species, that include multiple copies of clock-related genes. The triplicate genome of Brassica
rapa retains high sequence-level co-linearity with Arabidopsis genomes. In B. rapa we had previously identified five orthologs of the five known Arabidopsis pseudo-response regulator (PRR) genes that are key regulators of the circadian clock in this species. Three of these B. rapa genes, BrPRR1, BrPPR5, and BrPPR7, are present in two copies each in the B. rapa genome, for a total of eight B. rapa PRR (BrPRR) orthologs. We have now determined sequences and expression characteristics of the eight BrPRR genes and mapped their positions in the B. rapa genome. Although both members of each paralogous pair exhibited the same expression pattern, some variation in their gene
structures was apparent. The BrPRR genes are tightly linked to several flowering genes. The knowledge about genome location, copy number variation and structural
diversity of these B. rapa clock genes will improve our understanding of clock-related functions in this important crop. This will facilitate the development
of Brassica crops for optimal growth in new environments and under changing conditions. 相似文献
6.
7.
D. K. Yadava Swarup K. Parida V. K. Dwivedi A. Varshney Irfan A. Ghazi V. Sujata T. Mohapatra 《Journal of plant biochemistry and biotechnology.》2009,18(1):29-36
The present study was carried out with the objective of evaluating genomic STMS markers developed earlier in Brassica napus, B. oleracea, B. rapa and B. nigra for their use in Brassica juncea and B. carinata. Ninety-six of the 100 STMS markers used under standardized annealing temperatures and gel concentrations produced clear reproducible amplification pattern. For majority of the markers 60 °C annealing temperature and 3.5% metaphor agarose gel were found suitable. High cross-transferability of STMS markers to related Brassica species including B. carinata (91.6%) and B. juncea (87.5%) suggested the possibility of utilizing these markers for genome analysis in the species where no such markers are available. The ‘B’ genome derived markers showed lower level of transferability to the ‘A’ and ‘C’ genome Brassica species. The potential of STMS markers to detect polymorphism among Brassica species and genera was 98.9%. The level of inter-specific polymorphism was much higher than the intea-specific polymorphism. The markers capable of revealing polymorphism among Brassica species and genera would be useful in Brassica introgression breeding programme. The polymorphic markers were found efficient in establishing the expected evolutionary relationships among the six different Brassica species and two related genera. Low level of intra-specific polymorphism revealed by these markers suggested use of a large set of such markers for various applications in Brassica genetics, genomics and breeding. 相似文献
8.
Entang Tian Yingfen Jiang Lunlin Chen Jun Zou Fei Liu Jinling Meng 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(8):1431-1440
Allopolyploidy plays an important role in plant evolution and confers obvious advantages on crop growth and breeding compared to low ploidy levels. The present investigation was aimed at synthesising the first known chromosomally stable hexaploid Brassica with the genome constitution AABBCC. More than 2,000 putative hexaploid plants were obtained through large-scale hybridisation from various combinations of crosses between different cultivars of Brassica carinata (BBCC) and B. rapa (AA). The majority of plants after two generations of selfing within selected hexaploid plants (H2) were aneuploid, and only 80 plants (4.6%) had the expected hexaploid chromosome number (2n = 54). The hexaploid ratio increased to an average of 23.0 and 26.3% in the H3 and H4 generations, respectively, and was accompanied by an increase in pollen fertility. The appearance of aneuploid plants in each generation could be detected having various chromosomal abnormalities at meiosis. The frequency of hexaploid plants varied significantly among different cultivar combinations, from 0 to 56% in the H4 generation, and it showed a positive correlation with pollen fertility. The frequency of SSR allelic fragments lost or novel alleles gained was significantly lower in H4 than in H2 and H3, which reflects increasing genome stability in H4. The A and C genomes were significantly less stable than the B genome, which may mainly result from frequent homoeologous pairing and rearrangements between the A and C genomes. Methods to establish a stable hexaploid Brassica crop by intercrossing these lines followed by intensive selection are also discussed. 相似文献
9.
Researchers recognized early that chromosome behavior, as other morphological characters, is under genetic control and gave
some cytogenetical examples such as the homoeologous chromosome pairing in wheat. In the intergeneric sexual hybrids between
cultivated Brassica species and another crucifer Orychophragmus violaceus, the phenomenon of parental genome separation was found under genetic control during mitosis and meiosis. The cytogenetics
of these hybrids was species-specific for Brassica parents. The different chromosome behavior of hybrids with three Brassica diploids (B. rapa, B. nigra and B. oleracea) might contribute to the different cytology of hybrids with three tetraploids (B. napus, B. juncea and B. carinata). The finding that genome-specific retention or loss of chromosomes in hybrids of O. violaceus with B. carinata and synthetic Brassica hexaploids (2n=54, AABBCC) is likely related to nucleolar dominance gives new insight into the molecular mechanisms regarding the cytology
in these hybrids. It is proposed that the preferential expressions of genes for centromeric proteins from one parent (such
as the well presented centromeric histone H3) are related with chromosome stability in wide hybrids and nucleolar dominance
is beneficial to the production of centromere-specific proteins of the rRNAs-donor parent and to the stability of its chromosomes. 相似文献
10.
Foo Cheung Martin Trick Nizar Drou Yong Pyo Lim Jee-Young Park Soo-Jin Kwon Jin-A Kim Rod Scott J. Chris Pires Andrew H. Paterson Chris Town Ian Bancroft 《The Plant cell》2009,21(7):1912-1928
Homoeologous regions of Brassica genomes were analyzed at the sequence level. These represent segments of the Brassica A genome as found in Brassica rapa and Brassica napus and the corresponding segments of the Brassica C genome as found in Brassica oleracea and B. napus. Analysis of synonymous base substitution rates within modeled genes revealed a relatively broad range of times (0.12 to 1.37 million years ago) since the divergence of orthologous genome segments as represented in B. napus and the diploid species. Similar, and consistent, ranges were also identified for single nucleotide polymorphism and insertion-deletion variation. Genes conserved across the Brassica genomes and the homoeologous segments of the genome of Arabidopsis thaliana showed almost perfect collinearity. Numerous examples of apparent transduplication of gene fragments, as previously reported in B. oleracea, were observed in B. rapa and B. napus, indicating that this phenomenon is widespread in Brassica species. In the majority of the regions studied, the C genome segments were expanded in size relative to their A genome counterparts. The considerable variation that we observed, even between the different versions of the same Brassica genome, for gene fragments and annotated putative genes suggest that the concept of the pan-genome might be particularly appropriate when considering Brassica genomes. 相似文献
11.
D. Struss C. F. Quiros J. Plieske G. Röbbelen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(7):1026-1032
The three B genomes of Brassica contained in B. nigra, B. carinata and B. juncea were dissected by addition in B. napus. Using phenotypic, isozyme and molecular markers we characterized 8 alien B-genome chromosomes from B. nigra and B. carinata and 7 from B. juncea by constructing synteney groups. The alien chromosomes of the three different sources showed extensive intragenomic recombinations that were detected by the presence of the same loci in more than one synteny group but flanked by different markers. In addition, intergenomic recombinations were observed. These were evident in euploid AACC plants of the rapeseed phenotype derived from the addition lines carrying a few markers from the B genome due to translocations and recombinations between non-homoeologous chromosomes. The high plasticity of the Brassica genomes may have been an powerful factor in directing their evolution by hybridization and amphiploidy. 相似文献
12.
Feng Cheng Terezie Mandáková Jian Wu Qi Xie Martin A. Lysak Xiaowu Wang 《The Plant cell》2013,25(5):1541-1554
The genus Brassica includes several important agricultural and horticultural crops. Their current genome structures were shaped by whole-genome triplication followed by extensive diploidization. The availability of several crucifer genome sequences, especially that of Chinese cabbage (Brassica rapa), enables study of the evolution of the mesohexaploid Brassica genomes from their diploid progenitors. We reconstructed three ancestral subgenomes of B. rapa (n = 10) by comparing its whole-genome sequence to ancestral and extant Brassicaceae genomes. All three B. rapa paleogenomes apparently consisted of seven chromosomes, similar to the ancestral translocation Proto-Calepineae Karyotype (tPCK; n = 7), which is the evolutionarily younger variant of the Proto-Calepineae Karyotype (n = 7). Based on comparative analysis of genome sequences or linkage maps of Brassica oleracea, Brassica nigra, radish (Raphanus sativus), and other closely related species, we propose a two-step merging of three tPCK-like genomes to form the hexaploid ancestor of the tribe Brassiceae with 42 chromosomes. Subsequent diversification of the Brassiceae was marked by extensive genome reshuffling and chromosome number reduction mediated by translocation events and followed by loss and/or inactivation of centromeres. Furthermore, via interspecies genome comparison, we refined intervals for seven of the genomic blocks of the Ancestral Crucifer Karyotype (n = 8), thus revising the key reference genome for evolutionary genomics of crucifers. 相似文献
13.
Kwangsoo Cho Carmel M. O’Neill Soo‐Jin Kwon Tae‐Jin Yang Andrew M. Smooker Fiona Fraser Ian Bancroft 《The Plant journal : for cell and molecular biology》2010,61(4):591-599
We conducted a sequence‐level comparative analyses, at the scale of complete bacterial artificial chromosome (BAC) clones, between the genome of the most economically important Brassica species, Brassica napus (oilseed rape), and those of Brassica rapa, the genome of which is currently being sequenced, and Arabidopsis thaliana. We constructed a new B. napus BAC library and identified and sequenced clones that contain homoeologous regions of the genome including stearoyl‐ACP desaturase‐encoding genes. We sequenced the orthologous region of the genome of B. rapa and conducted comparative analyses between the Brassica sequences and those of the orthologous region of the genome of A. thaliana. The proportion of genes conserved (~56%) is lower than has been reported previously between A. thaliana and Brassica (~66%). The gene models for sets of conserved genes were used to determine the extent of nucleotide conservation of coding regions. This was found to be 84.2 ± 3.9% and 85.8 ± 3.7% between the B. napus A and C genomes, respectively, and that of A. thaliana, which is consistent with previous results for other Brassica species, and 97.5 ± 3.1% between the B. napus A genome and B. rapa, and 93.1 ± 4.9% between the B. napus C genome and B. rapa. The divergence of the B. napus genes from the A genome and the B. rapa genes was greater than anticipated and indicates that the A genome ancestor of the B. napus cultivar studied was relatively distantly related to the cultivar of B. rapa selected for genome sequencing. 相似文献
14.
Z. Li J. G. Wu Y. Liu H. L. Liu W. K. Heneen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(2):251-265
Intergeneric hybrids between Brassica juncea (2n=36), B. carinata (2n=34) and Orychophragmus violaceus (2n=24) were produced when B. juncea and B. carinata cultivars were used as female parents. The hybrids between B. juncea and O. violaceus had an intermediate morphology except for petal colour and were partially fertile. The hybrids between B. carinata and O. violaceus had a matroclinous morphology and were nearly fertile. Cytological analysis of the hybrids and their progenies gave the following
results. (1) In the hybrids between B. juncea and O. violaceus, the somatic tissues of the roots, leaves and styles were mixoploid (2n=12–42), and cells with 24, 30 or 36 chromosomes were
the most frequent. Based on the recorded numbers and behaviour of the mitotic and meiotic chromosomes, complete and partial
separation of the parental genomes was proposed to have occurred during mitosis. This resulted in the occurrence of cells
with possibly complete and incomplete complements of the parental species and cells with parental complements and some additional
chromosomes from the other parent. (2) Pollen mother cells (PMCs) possibly with both parental chromosome complements, only
B. juncea chromosomes or a complete B. juncea complement with additional O. violaceus chromosomes were more competitive in entering meiosis. The majority of fertile gametes were deduced to have been produced
by PMCs with a B. juncea complement with or without additional O. violaceus chromosomes. (3) The progeny plants from selfed hybrids between B. juncea and O. violaceus were morphologically either of a B. juncea, hybrid or variable type. Cytologically they were grouped into six types according to the frequencies of cells with various
chromosome numbers. All of the plants except 2 which constituted two types, were mixoploids, composed of cells with various
chromosome numbers, mainly in a certain serial range. (4) The hybrid plants between B. carinata and O. violaceus were mixoploids with chromosome numbers in the range of 12–34, and cells with 2n=34 were the most frequent. The main categories
of PMCs with 17 bivalents at metaphase I and 17 : 17 segregations at anaphase I contributed to the high fertility of the hybrids
and the fact that their progeny after selfing were mainly plants with 2n=34. Somatic and meiotic separation of the parental
genomes was proposed to have occurred in the hybrids between B. carinata and O. violaceus. (5) Mitotic and meiotic elimination of what could be O. violaceus chromosomes might also have contributed to the observed mitotic and meiotic cell types in the two kinds of hybrids studied.
Finally, the possible mechanisms behind these cytological observations and their potential in the production of Brassica aneuploids were discussed.
Received: 4 February 1997/Accepted: 29 July 1997 相似文献
15.
Y. Takahata T. Takeda 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,80(1):38-42
Summary Intergeneric hybrids between Moricandia arvensis (C3–C4 intermediate species) and Brassica A and B genome species (B. campestris and B. nigra) were produced via ovary culture. When M. arvensis was used as a female parent, the hybrid embryo yield (0.25–0.45 embryo per pollination) was similar between two genomes, regardless of the male parent. The reciprocal hybrid using B. campestris as a female was also obtained, although yield of embryo was lower (0.02 embryo per pollination). On the other hand, no hybrids were obtained without the in vitro technique. As most hybrid embryos could not develop normal shoots, plants were regenerated by inducing shoots on the cultured hypocotyl. The hybrid nature of the regenerated plant was confirmed morphologically and cytogenetically. A certain amount of bivalents (2.52-2.71) in the hybrids indicated the existence of partial chromosome homology between two genera. The present results indicate that ovary culture is an effective technique for overcoming the crossing barrier between M. arvensis and Brassica cultivated species. 相似文献
16.
17.
R. J. Snowdon W. Köhler W. Friedt A. Köhler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(8):1320-1324
Genomic in situ hybridization (GISH) methods were used to detect different genome components within Brassica amphidiploid species and to identify donor chromatin in hybrids between Brassica napus and Raphanus sativus. In Brassica juncea and Brassica carinata the respective diploid donor genomes could be reliably distinguished by GISH, as could all R-genome chromosomes in the intergeneric
hybrids. The A- and C-genome components in B. napus could not be clearly distinguished from one another using GISH, confirming the considerable homoeology between these genomes.
GISH methods will be extremely beneficial for monitoring chromatin transfer and introgression in interspecific Brassica hybrids.
Received: 20 May 1997 / Accepted: 28 July 1997 相似文献
18.
Jingyin Yu Sadia Tehrim Fengqi Zhang Chaobo Tong Junyan Huang Xiaohui Cheng Caihua Dong Yanqiu Zhou Rui Qin Wei Hua Shengyi Liu 《BMC genomics》2014,15(1)
Background
Plant disease resistance (R) genes with the nucleotide binding site (NBS) play an important role in offering resistance to pathogens. The availability of complete genome sequences of Brassica oleracea and Brassica rapa provides an important opportunity for researchers to identify and characterize NBS-encoding R genes in Brassica species and to compare with analogues in Arabidopsis thaliana based on a comparative genomics approach. However, little is known about the evolutionary fate of NBS-encoding genes in the Brassica lineage after split from A. thaliana.Results
Here we present genome-wide analysis of NBS-encoding genes in B. oleracea, B. rapa and A. thaliana. Through the employment of HMM search and manual curation, we identified 157, 206 and 167 NBS-encoding genes in B. oleracea, B. rapa and A. thaliana genomes, respectively. Phylogenetic analysis among 3 species classified NBS-encoding genes into 6 subgroups. Tandem duplication and whole genome triplication (WGT) analyses revealed that after WGT of the Brassica ancestor, NBS-encoding homologous gene pairs on triplicated regions in Brassica ancestor were deleted or lost quickly, but NBS-encoding genes in Brassica species experienced species-specific gene amplification by tandem duplication after divergence of B. rapa and B. oleracea. Expression profiling of NBS-encoding orthologous gene pairs indicated the differential expression pattern of retained orthologous gene copies in B. oleracea and B. rapa. Furthermore, evolutionary analysis of CNL type NBS-encoding orthologous gene pairs among 3 species suggested that orthologous genes in B. rapa species have undergone stronger negative selection than those in B .oleracea species. But for TNL type, there are no significant differences in the orthologous gene pairs between the two species.Conclusion
This study is first identification and characterization of NBS-encoding genes in B. rapa and B. oleracea based on whole genome sequences. Through tandem duplication and whole genome triplication analysis in B. oleracea, B. rapa and A. thaliana genomes, our study provides insight into the evolutionary history of NBS-encoding genes after divergence of A. thaliana and the Brassica lineage. These results together with expression pattern analysis of NBS-encoding orthologous genes provide useful resource for functional characterization of these genes and genetic improvement of relevant crops.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-3) contains supplementary material, which is available to authorized users. 相似文献19.
20.
Genetic changes in a novel breeding population of Brassica napus synthesized from hundreds of crosses between B. rapa and B. carinata
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Jun Zou Annaliese S. Mason Xueqi Shen Xiaohua Wang Nian Wang Fabian Grandke Meng Wang Shihao Chang Rod J. Snowdon Jinling Meng 《Plant biotechnology journal》2018,16(2):507-519
Introgression of genomic variation between and within related crop species is a significant evolutionary approach for population differentiation, genome reorganization and trait improvement. Using the Illumina Infinium Brassica 60K SNP array, we investigated genomic changes in a panel of advanced generation new‐type Brassica napus breeding lines developed from hundreds of interspecific crosses between 122 Brassica rapa and 74 Brassica carinata accessions, and compared them with representative accessions of their three parental species. The new‐type B. napus population presented rich genetic diversity and abundant novel genomic alterations, consisting of introgressions from B. rapa and B. carinata, novel allelic combinations, reconstructed linkage disequilibrium patterns and haplotype blocks, and frequent deletions and duplications (nonrandomly distributed), particularly in the C subgenome. After a much shorter, but very intensive, selection history compared to traditional B. napus, a total of 15 genomic regions with strong selective sweeps and 112 genomic regions with putative signals of selective sweeps were identified. Some of these regions were associated with important agronomic traits that were selected for during the breeding process, while others were potentially associated with restoration of genome stability and fertility after interspecific hybridization. Our results demonstrate how a novel method for population‐based crop genetic improvement can lead to rapid adaptation, restoration of genome stability and positive responses to artificial selection. 相似文献