Rich genetic resources are contained among wheat wild relatives. Cytogenetics Institute of Nanjing Agricultural University commences to transfer these genetic resources from relatives into common wheat. The hybrids be...Rich genetic resources are contained among wheat wild relatives. Cytogenetics Institute of Nanjing Agricultural University commences to transfer these genetic resources from relatives into common wheat. The hybrids between common wheat and Haynaldia villosa, Leymus racemosus,Roegneria ciliaris, Roegneria Kamoji, Secale cereale or Thinopyrum baserabicum, and their alien chromosome stocks such as addition, substitution, translocation and introgression lines were developed via successive pollinations and immature embryo rescues. The resulted progenies were characterized using mitotic and meiotic analysis combining with chromosome banding and in situ hybridization. Isozyme pattern and RFLP analysis were used to determine the homoeologous relationship between alien chromosomes and those of common wheat. Irradiation, Ph system (homoeologous pairing control system), gametocidal chromosome effect were successfully employed to induce translocation and deletion lines. Chromosome C banding, in situ hybridization, RFLP and trait tracing were used to identify alien chromosome, chromosome segments, breakage point of translocation or deletion, and to map the introgressed genes such as those conferring resistance to powdery mildew, yellow rust, Fusarium head blight and take all diseases. As the result of above effort, new genetic materials, which contained multiple useful alien genes, were developed. To improve the agronomic characters of the derived lines, back crosses or “rolling” crosses using superior varieties or lines as recurrent parents are currently being conducted.展开更多
A total of 206 SSR （Simple Sequence Repeats） primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were d...A total of 206 SSR （Simple Sequence Repeats） primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were detected in 31 Yunnan, 15 Tibetan and 6 Xinjiang wheat accessions with an average of PIC values 0.2764, 0.3082, and 0.1944, respectively. Substantial differences in allelic polymorphisms were detected by SSR markers in all the 21 chromosomes, the 7 homoeologous groups, and the three genomes （A, B, and D） in Yunnan, Tibetan, and Xinjiang wheat. The highest and lowest allelic polymorphisms in all the 21 chromosomes were observed in 3B and 1D chromosomes, respectively. The lowest and highest allelic polymorphisms among the seven homoeologous groups was observed in 6 and 3 homoeologous groups, respectively. Among the three genomes, B genome showed the highest, A the intermediate, and D the lowest allelic polymorphism. The genetic distance （GD） indexes within Yunnan, Tibetan, and Xinjiang wheat, and between different wheat types were calculated. The GD value was found to be much higher within Yunnan and Tibetan wheat than within Xinjiang wheat, but the GD value between Yunnan and Tibetan wheat was lower than those between Yunnan and Xinjiang wheat, and between Tibetan and Xinjiang wheat. The cluster analysis indicated a closer relationship between Yunnan and Tibetan wheat than that between Yunnan and Xinjiang wheat or between Tibetan and Xinjiang wheat.展开更多
文摘Rich genetic resources are contained among wheat wild relatives. Cytogenetics Institute of Nanjing Agricultural University commences to transfer these genetic resources from relatives into common wheat. The hybrids between common wheat and Haynaldia villosa, Leymus racemosus,Roegneria ciliaris, Roegneria Kamoji, Secale cereale or Thinopyrum baserabicum, and their alien chromosome stocks such as addition, substitution, translocation and introgression lines were developed via successive pollinations and immature embryo rescues. The resulted progenies were characterized using mitotic and meiotic analysis combining with chromosome banding and in situ hybridization. Isozyme pattern and RFLP analysis were used to determine the homoeologous relationship between alien chromosomes and those of common wheat. Irradiation, Ph system (homoeologous pairing control system), gametocidal chromosome effect were successfully employed to induce translocation and deletion lines. Chromosome C banding, in situ hybridization, RFLP and trait tracing were used to identify alien chromosome, chromosome segments, breakage point of translocation or deletion, and to map the introgressed genes such as those conferring resistance to powdery mildew, yellow rust, Fusarium head blight and take all diseases. As the result of above effort, new genetic materials, which contained multiple useful alien genes, were developed. To improve the agronomic characters of the derived lines, back crosses or “rolling” crosses using superior varieties or lines as recurrent parents are currently being conducted.
基金Hi-Tech Research and Development (863) Program of China (No. 2006AA10Z1F6)Hi-Tech Re-search of Jiangsu Province (No.BG2005310)+2 种基金the Program for Changjiang Scholars and Innovative Research Team in University (No.10418) (PCSIRT)Innovation Foundation of Young Science and Technology of Nanjing Agriculture UniversityIntroduction of Talents Foundation of Nanjing Agriculture University.
文摘A total of 206 SSR （Simple Sequence Repeats） primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were detected in 31 Yunnan, 15 Tibetan and 6 Xinjiang wheat accessions with an average of PIC values 0.2764, 0.3082, and 0.1944, respectively. Substantial differences in allelic polymorphisms were detected by SSR markers in all the 21 chromosomes, the 7 homoeologous groups, and the three genomes （A, B, and D） in Yunnan, Tibetan, and Xinjiang wheat. The highest and lowest allelic polymorphisms in all the 21 chromosomes were observed in 3B and 1D chromosomes, respectively. The lowest and highest allelic polymorphisms among the seven homoeologous groups was observed in 6 and 3 homoeologous groups, respectively. Among the three genomes, B genome showed the highest, A the intermediate, and D the lowest allelic polymorphism. The genetic distance （GD） indexes within Yunnan, Tibetan, and Xinjiang wheat, and between different wheat types were calculated. The GD value was found to be much higher within Yunnan and Tibetan wheat than within Xinjiang wheat, but the GD value between Yunnan and Tibetan wheat was lower than those between Yunnan and Xinjiang wheat, and between Tibetan and Xinjiang wheat. The cluster analysis indicated a closer relationship between Yunnan and Tibetan wheat than that between Yunnan and Xinjiang wheat or between Tibetan and Xinjiang wheat.
