Dasypyrum villosum, an important genetic and trait resource for hexaploid wheat engineering

Authors: WU, NAN - Nanjing Agricultural University; HE, ZIMING - Nanjing Agricultural University; FANG, JIAXIN - Nanjing Agricultural University; LIU, XIN - Nanjing Agricultural University; SHEN, XIA - Nanjing Agricultural University; ZHANG, JUAN - Nanjing Agricultural University; LEI, YANHONG - Nanjing Agricultural University; XIA, YATING - Nanjing Agricultural University; HE, HUAGANG - Jiangsu University; LIU, WENXUAN - Henan Agricultural University; Chu, Chenggen; WANG, CONGLEI - Tianjin Academy Of Agricultural Sciences; QI, ZENGJUN - Nanjing Agricultural University

Submitted to: Annals of Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/12/2022
Publication Date: 4/22/2022
Citation: Wu, N., He, Z., Fang, J., Liu, X., Shen, X., Zhang, J., Lei, Y., Xia, Y., He, H., Liu, W., Chu, C.N., Wang, C., Qi, Z. 2022. Dasypyrum villosum, an important genetic and trait resource for hexaploid wheat engineering. Annals Of Botany. https://doi.org/10.1093/aob/mcac054.
DOI: https://doi.org/10.1093/aob/mcac054

Interpretive Summary: Mosquito grass is a wild species related to wheat that possesses many beneficial genes conferring resistance to several devastating wheat diseases as well as tolerance to environmental stresses. The highly diversified genetic background among mosquito grass accessions collected from around the world makes this species particularly useful for improving wheat characteristics and enhancing wheat genetic diversity. Analysis of genetic differences between accessions provided important information for using mosquito grass as a gene source in wheat breeding. In this research, a set of mosquito grass accessions collected from different countries were analyzed using different molecular tools, which revealed abundant variations on each chromosome among mosquito grass accessions. The unique fluorescence signals shown on each chromosome of mosquito grass in different accessions will be useful markers for incorporating mosquito grass beneficial genes into wheat through chromosome engineering techniques. In addition, new plant material developed from crossing emmer wheat with mosquito grass will provide progenies that can easily cross with wheat, which will provide another important genetic resource for wheat breeding. Taken together, this research has shown that mosquito grass can be a sustainable genetic resource for wheat improvement.

Technical Abstract: Dasypyrum villosum harbors abundant beneficial genes for wheat improvement. Owing to its open-pollinated nature, a high level of chromosome diversity likely exists among accessions. Therefore, application of D. villosum accessions in wheat breeding can contribute to increasing wheat genetic diversity in addition to trait improvement. Revealing genetic polymorphisms among D. villosum accessions will be important for directing their usage in wheat breeding. In this study, thirteen D. villosum accessions originated from Bulgaria, Turkey, Italy, Greece, and the United Kingdom were used to investigate chromosome polymorphisms. FISH through Multiplex Oligonucleotides Probes ONPM#4, GISH and molecular markers were used to detect polymorphisms of D. villosum chromosomes among accessions, and data of polymorphic signal block types, chromosome heterogeneity and heterozygosity, and chromosome polymorphic information content (CPIC) were used for analyzing genetic diversity of D. villosum. Consensus karyotypes of D. villosum were developed, and homoeologous status of D. villosum chromosomes corresponding to wheat homoeologous groups were determined. The tandem repeat probes of AFA family, pSc119.2 and (GAA)10 produced high-resolution signals not only showed the differences on D. villosum chromosomes but also revealed variation of tandem repeat distribution among chromosomes as well as accessions. A total of 106 polymorphic D. villosum chromosomes were identified and high level of heterozygosity and heterogeneity were observed. A subset of 56 polymorphic chromosomes including fifteen from chromosome 1V, six from 2V, and seven from each of the rest five D. villosum chromosomes were carried in two newly developed durum - D. villosum amphidiploids. This research indicated that D. villosum will be a sustainable genetic resource not only improves traits but also broadens genetic base of wheat.