摘要
Agropyron cristatum, a wild relative of common wheat(Triticum aestivum L.), provides many desirable genetic resources for wheat improvement, such as tolerance to cold, drought, and disease. To transfer and utilize these desirable genes, in this study, two wheat-A. cristatum derivatives II-13 and II-23 were identified and analyzed. We found that the number of root tip cell chromosomes was 44 in both II-13 and II-23, but there were four and six P genome chromosomes in II-13 and II-23, respectively, based on genomic in situ hybridization(GISH). The chromosome configurations of II-13 and II-23 were both 2 n=22 II by the meiotic analysis of pollen mother cells(PMCs) at metaphase I, indicating that there were two and three pairs of P chromosomes in II-13 and II-23, respectively. Notably, wheat chromosome 7 D was absent in derivative line II-13 while II-23 lacked chromosomes 4 B and 7 A based on SSR analysis combining fluorescence in situ hybridization(FISH) analysis with p As1 and p Sc119.2 as probes. Chromosomes 2 P and 7 P were detected in both II-13 and II-23. Another pair of P genome chromosomes in II-23 was determined to be 4 P based on expressed-sequences tags-sequence tagged sites(EST-STS) markers specific to A. cristatum and FISH with probes p Ac TRT1 and p Acp CR2. Overall, these results suggest that II-13 was a 7 P(7 D) substitution line with one pair of additional 2 P chromosomes and II-23 was a multiple 4 P(4 B), 7 P(7 A) substitution line with one pair of additional 2 P chromosomes. Moreover, we obtained six alien disomic addition lines and five alien disomic substitution lines by backcrossing. These new materials will allow desirable genes from A. cristatum to be used in common wheat.
Agropyron cristatum, a wild relative of common wheat(Triticum aestivum L.), provides many desirable genetic resources for wheat improvement, such as tolerance to cold, drought, and disease. To transfer and utilize these desirable genes, in this study, two wheat-A. cristatum derivatives II-13 and II-23 were identified and analyzed. We found that the number of root tip cell chromosomes was 44 in both II-13 and II-23, but there were four and six P genome chromosomes in II-13 and II-23, respectively, based on genomic in situ hybridization(GISH). The chromosome configurations of II-13 and II-23 were both 2 n=22 II by the meiotic analysis of pollen mother cells(PMCs) at metaphase I, indicating that there were two and three pairs of P chromosomes in II-13 and II-23, respectively. Notably, wheat chromosome 7 D was absent in derivative line II-13 while II-23 lacked chromosomes 4 B and 7 A based on SSR analysis combining fluorescence in situ hybridization(FISH) analysis with p As1 and p Sc119.2 as probes. Chromosomes 2 P and 7 P were detected in both II-13 and II-23. Another pair of P genome chromosomes in II-23 was determined to be 4 P based on expressed-sequences tags-sequence tagged sites(EST-STS) markers specific to A. cristatum and FISH with probes p Ac TRT1 and p Acp CR2. Overall, these results suggest that II-13 was a 7 P(7 D) substitution line with one pair of additional 2 P chromosomes and II-23 was a multiple 4 P(4 B), 7 P(7 A) substitution line with one pair of additional 2 P chromosomes. Moreover, we obtained six alien disomic addition lines and five alien disomic substitution lines by backcrossing. These new materials will allow desirable genes from A. cristatum to be used in common wheat.
基金
supported by the National Key Research and Development Program of China (2016YFD0100102)
