Agropyron cristatum (L.) Gaertn. (2n = 4x = 28, PPPP), one of the most important wild relatives of wheat, harbors many desirable genes for wheat genetic improvement. Development of wheat-A. cristatum translocation lines with superior agronomic traits facilitates wheat genetic improvement. In this study, 5106-DS was identified to be a wheat-A. cristatum 6P (6D) disomic substitution line using cytogenetic identification and molecular markers analysis, which displayed higher thousand-grain weight than its wheat parent Triticum aestivum cv. Fukuhokomugi (2n = 6x = 42, AABBDD). Analysis of its backcross populations indicated that there might be genes conferring increased grain weight and width on the chromosome 6P of 5106-DS. In the backcross population, we found three plants as Robertsonian translocation lines, created by chromosome centric breakage-fusion. Among them, there are one T6DS·6PL and two T6PS·6DL Robertsonian translocation lines. Additionally, the centromeres of these three translocation lines were determined to be fused centromeres of 6D and 6P using the probes pAcCR1 and pCCS1. The development of Robertsonian translocation lines would promote the utilization of A. cristatum chromosome 6P in wheat improvement.

冰草 ( Agropyron cristatatum ) (L.) Gaertn. (2 n  = 4 x  = 28, PPPP) 是小麦最重要的野生近缘种之一，拥有许多小麦遗传改良所需的基因。开发具有优良农艺性状的小麦-A.cristatatum易位系有利于小麦遗传改良。本研究通过细胞遗传学鉴定和分子标记分析，将5106-DS鉴定为小麦-A. cristatum 6P（6D）二体替代系，其千粒重高于其小麦亲本Triticum aestivum cv. 5106-DS。Fukuhokomugi (2 n  = 6 x  = 42, AABBDD)。对其回交群体的分析表明，5106-DS 的 6P 染色体上可能存在赋予粒重和宽度增加的基因。在回交群体中，我们发现了三种植物作为罗伯逊易位系，由染色体中心断裂融合产生。其中，有1条T6DS·6PL和2条T6PS·6DL罗伯逊易位系。另外，使用探针pAcCR1和pCCS1确定这三个易位系的着丝粒是6D和6P的融合着丝粒。罗伯逊易位系的发展将促进冠毛麦6P染色体在小麦改良中的利用。