Location: Cereal Crops ResearchTitle: Meiotic homoeologous recombination-based alien gene introgression in the genomics era of wheat Author
|Zhang, Wei - North Dakota State University|
|Cao, Yaping - North Dakota State University|
|Zhang, Mingyi - North Dakota State University|
|Zhu, Xianwen - North Dakota State University|
|Ren, Shuangfeng - North Dakota State University|
|Cai, Xiwen - North Dakota State University|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/2/2016
Publication Date: 6/16/2017
Publication URL: http://handle.nal.usda.gov/10113/5729161
Citation: Zhang, W., Cao, Y., Zhang, M., Zhu, X., Ren, S., Long, Y., Gyawali, Y., Chao, S., Xu, S., Cai, X. 2017. Meiotic homoeologous recombination-based alien gene introgression in the genomics era of wheat. Crop Science. 57:1189-1198. doi: 10.2135/cropsci2016.09.0819.
Interpretive Summary: Wheat originated from natural hybridization of three diploid species. Such origin resulted in modern wheat crop having a narrow genetic resource. However, wheat has numerous wild relatives that can be used for expanding its genetic base through exchanging DNA sequences between wheat chromosomes and their related chromosomes from wild relative species. Traditionally, the laborious chromosome analyses have been employed to detect the wheat chromosomes containing the DNA sequences from wild relative species. This has limited the progress of alien gene introgression (transfer) in wheat improvement. In this research, we used a modified wheat line and highly-efficient DNA marker technologies to identify and facilitate the exchanges between wheat chromosome 2B and its genetically-related chromosomes 2S and 2E derived from goat-grass species Aegilops speltoides and tall wheat-grass species Thinopyrum elongatum, respectively. Several wheat lines carrying 2B-2S and 2B-2E interchanges and associated DNA markers were successfully developed. The results indicated that the DNA marker-mediated approach described in this study can enhance the recovery and detection of chromosome interchanges for alien gene introgression and boost the utilization of desirable genes in wild relative species for wheat improvement.
Technical Abstract: Wheat (Triticum spp.) has a narrow genetic basis due to its allopolyploid origin. However, wheat has numerous wild relatives usable for expanding genetic variability of its genome through meiotic homoeologous recombination. Traditionally, laborious cytological analyses have been employed to detect homoeologous recombination. This has limited the progress of alien gene introgression in wheat improvement. Here, we used the ph1b mutant and high-throughput genotyping technologies to identify and facilitate homoeologous recombination-based alien gene introgression. Genotypes homozygous for ph1b and heterozygous for wheat chromosome 2B and its homoeologue in the wild species Aegilops speltoides Tausch (2S) and Thinopyrum elongatum (Host) D. R. Dewey (2E) were constructed to enhance 2B–2S and 2B–2E meiotic pairing and recombination. Backcross populations were subsequently developed to effectively recover and detect 2B–2S and 2B–2E homoeologous recombination events using the high-throughput, chip-based single-nucleotide polymorphism (SNP) assay and uniplex SNP-derived polymerase chain reaction (PCR) markers. This DNA marker-mediated approach will enhance the recovery and detection of meiotic homoeologous recombination for alien gene introgression and boost the utilization of alien genes in wheat improvement.