小麦-鹅观草第一部分同源群染色体渗入系鉴定与基因组归属分析

鹅观草（Roegneria kamoji，2n=42，SSHHYY）是小麦异源六倍体野生近缘种，对小麦赤霉病具有良好抗性，是改良小麦赤霉病抗性的重要遗传资源。通过远缘杂交，将鹅观草第一部分同源群染色体上的抗赤霉病基因Fhb6导入普通小麦。由于第一部分同源群染色体包含1S、1H和1Y三条染色体，为研究这些同源染色体对小麦赤霉病抗性的影响，筛选出4个鹅观草第一部分同源群染色体特异分子标记，通过PCR扩增鹅观草属不同野生种的基因组DNA，明确了抗赤霉病Fhb6基因位于鹅观草1Y#1染色体。进一步利用分子细胞遗传学技术从中国春与鹅观草的后代中选育出5份涉及鹅观草1Y#2和1S#2染色体的渗入系材料。其中：21RK?1为二体异代换系DS1Y#2(1A)，21RK?2为二体异代换系DS1S#2（1D），21RK?3为二体异附加系DA1S#2，21RK?4为1S#2和TW·1S#2S的双单体附加系，21RK?5为纯合TW·1S#2S易位系。这些新种质为小麦抗赤霉病基因的发掘及遗传改良奠定了基础。

Introgression and Characterization of the Homologous Group 1 Chromosomes from Roegneria kamoji into Common Wheat

Roegneria kamoji （2n=42， SSHHYY） is a hexaploid wild relatives of common wheat. Due to high resistance level of Fusarium head blight （FHB）， R. kamoji is regarded as a potential germplasm to explore FHB?resistant genes. The FHB resistance gene Fhb6 located on the homoeologous group 1 chromosome of R. kamoji had been introduced into common wheat through hybridization. The homoeologous group 1 chromosomes of R. kamoji included 1S， 1H or 1Y chromosome. In order to understand the effect of homoeologous chromosome on resistance of FHB， four STS markers specific to homoeologous group 1 chromosomes of R. kamoji werescreened. Subsequently， these markers were used to amplify the DNA samples of the disomic substitution line DS1RK#1（1A） carrying Fhb6 and the other relatives with different genomes. Results indicated that Fhb6 was located on 1Y#1 chromosome. Five new wheat?R. kamoji introgression lines involving 1Y#2 and 1S#2 chromosomes were identified from the backcross progeny of the second hybrid between Chinese Spring and R. kamoji. Of which， 21RK?1 was the disomic substitution line DS1Y#2（1A）， 21RK?2 was the disomic substitution line DS1S#2（1D）， 21RK?3 was the disomic addition line DA1S#2， 21RK?4 was the double monosomic addition line of 1S#2 and TW·1S#2S， and 21RK?5 was the homologous TW·1S#2S translocation line. These new germplasm resources and the specific molecular markers developed in the present study provided the foundation for the genetic improvement of wheat resistance to Fusarium head blight.