| Wheat is widely cultivated in the world and the total volume of its annual trade is higher than any other cereal crops. It plays an important role in the world economy. Like other natural disaster, the fungous disease of wheat is one of the main factors that affect the production of wheat. Stripe rust is the major fungous disease in wheat. For preventing the disease from breaking out, the application of resistance variety is the most economical way and it's safety for the environment. However, the disease-resistance power of wheat variety may lose with the evolution of new toxicant biological race after the variety is cultivated by the human beings. So it is necessary to develope new sources of stripe rust resistance and search for new gene with stripe rust resistance for wheat breeding. It's a good way to transfer new gene with stripe rust resistance from kindred plant into the cultivar by distant hybridization. Furthermore ,cytogentic analysis and exploration on the mechanism of gene with stripe rust resistance transfered are also needed for the application of the new germplasm speedily.Transfering gene resistant to stripe rust new races from hexaploid Triticale into common wheat by cross-fertilization between them as well as multiple back-crossing, nine new germplasms with stripe rust new races resistance were developed. In this study, basic cytogenetic identify of these new germplasms was conducted by using cytogenetic method, screen of strip rust resistance and elementary analysis of karyotype. Some mechanism that gene with strip rust resistance transfered from hexaploid triticale into common wheat was also explored .The results show:(l)Some abnormal frequency of chromosome pairing appeared in PMC MI in new germplasm * China Spring. Based on existed theory and combining with identify of strip rust resistance and elementary analysis of karyotype , we can conclude that SCV-3-4-100 is vsheat-triticale substitution line and other eight new germplasms ,TiKe-2-Hao, WTscv-3-1?WT25-2-11-4-100-1 , WT20-2-2A-118-100, WT25-2-11-3-102-1 , SCV-3-4-103-1 , WT20-7-1-24-100-1 , WT37-2-1R-12-25-6-2 are translation line and this kind of translocation is different from 1B/1R translocation line.(2): Percentage of seed set in reciprocal cross between triticale and common wheat were high, but percentage of seedling in reciprocal cross were very significant different. Percentage of seedling in hexaploid Tritical X common wheat was more high because endosperm developed very well than that in common wheat X hexaploid Tritical because endosperm developed bad. Many seeds and good seedling were obtained by back-crossing. (3): Abnormalities were observed in PMC MI in reciprocal cross between triticale andcommon wheat. The number of univalent in triticale x common wheat is higher than theoretical value, but lower in common wheat ^triticale than theoretical value. However, the number of divalent is lower than theroretical value in both of them. At the same time, the number of multivalent and rod divalent is higher in common wheat x triticale than triticale xcommon wheat. In common wheat ^hexaploid triticale, the exogenous genes are transferred by means of homoeologous chromosome pairing. But in hexaploid triticale x common wheat, they rely on the chromosome breakage and recombination.
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