Chromosome 2C from Aegilops cylindrica has the ability to induce chromosome breakage in common wheat （Tritivum aestivum）. In the BC1F3 generation of the T. aestivum cv. Chinese Spring and a hybrid between T. aestivu...Chromosome 2C from Aegilops cylindrica has the ability to induce chromosome breakage in common wheat （Tritivum aestivum）. In the BC1F3 generation of the T. aestivum cv. Chinese Spring and a hybrid between T. aestivum-Leymus racemosus Lr.7 addition line and T. aestivum-Ae, cylindrica 2C addition line, three disomic translocation addition lines （2n = 44） were selected by mitotic chromosome C-banding and genomic in situ hybridization. We further characterized these T. aestivum-L, racemosus translocation addition lines, NAU636, NAU637 and NAU638, by chromosome C-banding, in situ hybridization using the A- and D-genome-specific bacterial artificial chromosome （BAC） clones 676D4 and 9M13; plasmids pAsl and pSc119.2, and 45S rDNA; as well as genomic DNA of L. racemosus as probes, in combination with double ditelosomic test cross and SSR marker analysis. The translocation chromosomes were designated as T3AS-Lr7S, T6BS-Lr7S, and T5DS-Lr7L. The translocation line T3AS-Lr7S was highly resistant to Fusarium head blight and will be useful germplasm for resistance breeding.展开更多
In order to induce chromosome translocation between wheat chromosomes and chromosome 5Lr of Leymus racemosus, the mi- crosporocytes during meiosis of T. aestivum-L. racemosus disomic addition line DA5Lr were irradiate...In order to induce chromosome translocation between wheat chromosomes and chromosome 5Lr of Leymus racemosus, the mi- crosporocytes during meiosis of T. aestivum-L. racemosus disomic addition line DA5Lr were irradiated by 60Co γ-rays 800 R (100 R/min). Before flowering, the treated spikes were emasculated and bagged. After 2-3 d, the emasculated flowerets were pollinated using pollens from T. aestivum cv. Chinese Spring. One plant with two translocation chromosomes involved in both the long and short arm of 5Lr was detected in the M1 by GISH. The plant was crossed with line DA5Lr, and its progenies with one 5Lr and two translocation chromosomes were analyzed for chromosome pairing behavior in their pollen mother cells (PMCs). A cross-shaped configuration at diplonema and Z-shaped or ring-shaped quadrivalent configuration at metaphase I were observed, indicating that the two translocation chromosomes were reciprocal translocation. Chromosome C-banding indicated that the wheat chromosomes involved in the reciprocal translocation belonged to A- or D-genome. Fluorescence in situ hybridization using pSc119.2 and pAs1 as the probe found that only pAs1 signals were present in the wheat chromosome segments of the two translocation chromosomes. Combining these results, the reciprocal chromosomal translocation was designated as T7DS·5LrL/5LrS·7DL. The two transloca- tion chromosomes were found to be transmitted together in the gametes of heterozygous reciprocal translocation plants with the transmission ratios of 59.4% in the female gametes and 83.9% in the male gametes, revealing preferential pollen transmission. In the self-fertilized progenies of the heterozygous reciprocal translocation, a line with the homozygous translocation line with a pair of translocation chromosome T7DS·5LrL was identified. The T7DS·5Lr translocation line was highly resistant to wheat scab and can be used as a potential and new source in wheat improvement for scab resistance.展开更多
Leymus racemosus is highly resistant to wheat scab (Fusarum head bright). The transfer of scab resistant gene from L. racemosus to Triticum aestivum is of great significance for broadening the base of wheat resistance...Leymus racemosus is highly resistant to wheat scab (Fusarum head bright). The transfer of scab resistant gene from L. racemosus to Triticum aestivum is of great significance for broadening the base of wheat resistance. In the present study, the pollen of T. aestivum-L. racemosus monosomic addition line with scab resistance was treated by irradiation with 1200 R 60Co-γ-rays prior to pollinating to emasculated wheat cv. Mianyang 85-45. Nine plants with a telocentric chromosome 7Lr#1S were observed in M1, and one ditelosomic substitution line 7Lr#1S was selected from selfcrossing progenies and confirmed by chromosome C-banding and GISH. Furthermore, a co-dominant EST-SSR marker CINAU 31 was employed to identify this substitution line. A pair of chromosome 7A of common wheat were found to be replaced by a pair of telocentric chromosome 7Lr#1S, and further investigation showed that chromosome configuration of the substitution line at MI of PMCs after GISH was 17.50○II W + 2.19 IIW + 0.42II7Lr#1S + 1.08 I7Lr#1S + 0.69 IW. Two telocentric chromosomes paired as a bivalent in 59.7% of PMCs. Abnormal chromosome behaviors of telocentric chromosomes were observed in part of PMCs at anaphase I and telophase I, including the moving of two telocentric chromosomes to the same pole, lagging and earlier separation of their sister chromatid. All these abnormal behaviors can be grouped into three distinct types of tetrads according to different numbers of 7Lr#1S in their daughter cells and various micronucleus in some tetrads. However, due to the high transmission frequency of the female and male gametes with a 7Lr#1S, 84% of the selfcrossing progeny plants had ditelosomic substitution. The substitution line showed high resistance to wheat scab in a successive two-year test both in the greenhouse and field; hence, the line will be particularly valuable for alien gene mapping, small fragment translocation induction and telosomic cytological behavior analysis.展开更多
Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most widely distributed and destructive fungal diseases worldwide. Since 1995, most Chinese wheat cultivars have lost their stripe rust r...Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most widely distributed and destructive fungal diseases worldwide. Since 1995, most Chinese wheat cultivars have lost their stripe rust resistance due to the subsequent emergence of the new races CYR30, CYR31, CYR32, and CYR33 （Han et al., 2010）. Therefore, it is necessary to seek effective resistance genes and develop new resistance germ- plasm for wheat resistance breeding.展开更多
基金supported by the National Natural Science Foundation of China (No. 30270827 and 30871519)the Science and Technology Project of Jiangsu Province (No. BG20053107)+1 种基金the 111 Project of the Ministry of Education of ChinaCCRP Program of the McKnight Foundation.
文摘Chromosome 2C from Aegilops cylindrica has the ability to induce chromosome breakage in common wheat （Tritivum aestivum）. In the BC1F3 generation of the T. aestivum cv. Chinese Spring and a hybrid between T. aestivum-Leymus racemosus Lr.7 addition line and T. aestivum-Ae, cylindrica 2C addition line, three disomic translocation addition lines （2n = 44） were selected by mitotic chromosome C-banding and genomic in situ hybridization. We further characterized these T. aestivum-L, racemosus translocation addition lines, NAU636, NAU637 and NAU638, by chromosome C-banding, in situ hybridization using the A- and D-genome-specific bacterial artificial chromosome （BAC） clones 676D4 and 9M13; plasmids pAsl and pSc119.2, and 45S rDNA; as well as genomic DNA of L. racemosus as probes, in combination with double ditelosomic test cross and SSR marker analysis. The translocation chromosomes were designated as T3AS-Lr7S, T6BS-Lr7S, and T5DS-Lr7L. The translocation line T3AS-Lr7S was highly resistant to Fusarium head blight and will be useful germplasm for resistance breeding.
基金supported by the National High-Tech Research and Deve-lopment Program of China (Grant No. 2006AA10Z1F6)Programme of Introducing Talents of Discipline to Universities (Grant No. B08025)
文摘In order to induce chromosome translocation between wheat chromosomes and chromosome 5Lr of Leymus racemosus, the mi- crosporocytes during meiosis of T. aestivum-L. racemosus disomic addition line DA5Lr were irradiated by 60Co γ-rays 800 R (100 R/min). Before flowering, the treated spikes were emasculated and bagged. After 2-3 d, the emasculated flowerets were pollinated using pollens from T. aestivum cv. Chinese Spring. One plant with two translocation chromosomes involved in both the long and short arm of 5Lr was detected in the M1 by GISH. The plant was crossed with line DA5Lr, and its progenies with one 5Lr and two translocation chromosomes were analyzed for chromosome pairing behavior in their pollen mother cells (PMCs). A cross-shaped configuration at diplonema and Z-shaped or ring-shaped quadrivalent configuration at metaphase I were observed, indicating that the two translocation chromosomes were reciprocal translocation. Chromosome C-banding indicated that the wheat chromosomes involved in the reciprocal translocation belonged to A- or D-genome. Fluorescence in situ hybridization using pSc119.2 and pAs1 as the probe found that only pAs1 signals were present in the wheat chromosome segments of the two translocation chromosomes. Combining these results, the reciprocal chromosomal translocation was designated as T7DS·5LrL/5LrS·7DL. The two transloca- tion chromosomes were found to be transmitted together in the gametes of heterozygous reciprocal translocation plants with the transmission ratios of 59.4% in the female gametes and 83.9% in the male gametes, revealing preferential pollen transmission. In the self-fertilized progenies of the heterozygous reciprocal translocation, a line with the homozygous translocation line with a pair of translocation chromosome T7DS·5LrL was identified. The T7DS·5Lr translocation line was highly resistant to wheat scab and can be used as a potential and new source in wheat improvement for scab resistance.
基金the National Hi-Tech Research and Development Program of China (Grant No. 2006AA10Z1F6)National Natural Science Foundation of Jiangsu Province (Grant No. BK2006720)+1 种基金High Tech Research Plan of Jiangsu Province (Grant No. BG2005310)Program of Introducing Talents of Discipline to Universities (Grant No. B08025)
文摘Leymus racemosus is highly resistant to wheat scab (Fusarum head bright). The transfer of scab resistant gene from L. racemosus to Triticum aestivum is of great significance for broadening the base of wheat resistance. In the present study, the pollen of T. aestivum-L. racemosus monosomic addition line with scab resistance was treated by irradiation with 1200 R 60Co-γ-rays prior to pollinating to emasculated wheat cv. Mianyang 85-45. Nine plants with a telocentric chromosome 7Lr#1S were observed in M1, and one ditelosomic substitution line 7Lr#1S was selected from selfcrossing progenies and confirmed by chromosome C-banding and GISH. Furthermore, a co-dominant EST-SSR marker CINAU 31 was employed to identify this substitution line. A pair of chromosome 7A of common wheat were found to be replaced by a pair of telocentric chromosome 7Lr#1S, and further investigation showed that chromosome configuration of the substitution line at MI of PMCs after GISH was 17.50○II W + 2.19 IIW + 0.42II7Lr#1S + 1.08 I7Lr#1S + 0.69 IW. Two telocentric chromosomes paired as a bivalent in 59.7% of PMCs. Abnormal chromosome behaviors of telocentric chromosomes were observed in part of PMCs at anaphase I and telophase I, including the moving of two telocentric chromosomes to the same pole, lagging and earlier separation of their sister chromatid. All these abnormal behaviors can be grouped into three distinct types of tetrads according to different numbers of 7Lr#1S in their daughter cells and various micronucleus in some tetrads. However, due to the high transmission frequency of the female and male gametes with a 7Lr#1S, 84% of the selfcrossing progeny plants had ditelosomic substitution. The substitution line showed high resistance to wheat scab in a successive two-year test both in the greenhouse and field; hence, the line will be particularly valuable for alien gene mapping, small fragment translocation induction and telosomic cytological behavior analysis.
基金supported by the grants from the National High Technology Research and Development Program of China (No. 2011AA100102)the Chinese Academy of Sciences (No. KSCX2-EW-N-02)
文摘Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most widely distributed and destructive fungal diseases worldwide. Since 1995, most Chinese wheat cultivars have lost their stripe rust resistance due to the subsequent emergence of the new races CYR30, CYR31, CYR32, and CYR33 （Han et al., 2010）. Therefore, it is necessary to seek effective resistance genes and develop new resistance germ- plasm for wheat resistance breeding.
