小麦-鹅观草易位系T7A/1Rk#1的选育与鉴定

将小麦-鹅观草del1Rk#1L二体添加系的花粉用10 Gy 60Co γ射线照射处理，给小麦中国春授粉，获得杂种。综合利用C-分带、GISH、顺次C带/45SrDNA-FISH和顺次GISH/45SrDNA-FISH等分子细胞遗传学技术在M2代筛选和鉴定出1个涉及小麦7A和鹅观草1Rk#1染色体的相互易位染色体系，并获得1Rk#1染色体的1个45SrDNA位标，该位标和其对应的红色GISH-带纹能够特异地识别1Rk#1染色体短臂。对M2代群体染色体组成分析和测交分析表明，两条易位染色体在后代中以共分离方式成对出现，且易位通过雌配子的传递率高于雄配子。综合2004、2005和2006 3年的赤霉病抗性鉴定结果表明：该易位系对赤霉病表现部分抗病，但抗性表现在不同年份、不同地点有差异。试验还证明花粉辐射是诱导小麦-外缘物种染色体易位的有效方法。

Development and Identification of A Wheat-Roegneria Kamoji Translocation line T7A/1Rk#1

Pollen of Triticum aestivum-Roegneria kamoji del1Rk#1L disomic addition line, treated with 10 Gy 60Co γ rays, was pollinated to T.aestivum cv. Chinese Spring. A reciprocal chromosomal translocation line involving wheat 7A and R.kamoji 1Rk#1 was identified in M2 generation using the techniques including C-banding, GISH, sequential C-banding/45SrDNA-FISH, and sequential GISH/45SrDNA-FISH. A 45SrDNA locus and its corresponding red band in GISH pattern were observed specific to the short arm of 1Rk#1 and could be used as a landmark of 1Rk#1 chromosome. Analyses of chromosome constitution of M2 population and test-crosses showed that the reciprocal translocation chromosomes were co-segregated in offspring, and the transmitting ratios were both higher through female gametes than through male ones. The results of scab resistance identification in 2004, 2005 and 2006 showed that the translocation line conveyed scab resistance that varied in different years or different places. The experiment also showed that pollen irradiation is an effective method to induce wheat-alien chromosome translocations.