Jin X J, Sun D F, Li H Y, Yang Y, Sun G L
College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China.
Genet Mol Res. 2013 Sep 12;12(3):3555-65. doi: 10.4238/2013.September.12.2.
A spontaneous dwarf mutant of wheat was found in an F5 generation line derived from a cross between Huamai No. 9 and Een No. 1 in 1998; it was named Huaai 01. We characterized the genetic pattern of Huaai 01 and mapped the gene controlling the dwarf trait. This dwarf mutant was found insensitive to exogenous gibberellic acid treatment, based on the length of the first leaf and the coleoptile at the seedling stage, suggesting that it plays a crucial role in the gibberellin response pathway. Genetic analysis revealed that a single gene that is partially recessive controls the dwarf phenotype in Huaai 01. We named the dwarfing gene Rht-B2. Simple sequence repeats (SSR) were examined as identifying markers linked to the Rht-B2 gene in an F2 population. We screened 904 pairs of primers and identified 5 SSR markers linked to the Rht-B2 gene. Two markers, barc1096 and xgwm495, were located on the flanking region of the Rht-B2 gene at genetic distances of 2.9 and 3.3 cM, respectively. Based on published SSR linkage data for wheat, the Rht-B2 gene was mapped to the long arm of chromosome 4B. This identification and characterization of the Rht-B2 dwarfing gene will facilitate its utilization in wheat breeding.
1998年，在华麦9号与伊恩1号杂交所得的F5代品系中发现了一个小麦自发矮秆突变体，命名为淮01。我们对淮01的遗传模式进行了表征，并定位了控制矮秆性状的基因。基于幼苗期第一片叶和胚芽鞘的长度，发现该矮秆突变体对外源赤霉素处理不敏感，这表明它在赤霉素反应途径中起关键作用。遗传分析表明，一个部分隐性的单基因控制着淮01的矮秆表型。我们将该矮秆基因命名为Rht - B2。在一个F2群体中，对简单序列重复（SSR）进行检测，作为与Rht - B2基因连锁的鉴定标记。我们筛选了904对引物，鉴定出5个与Rht - B2基因连锁的SSR标记。两个标记barc1096和xgwm495分别位于Rht - B2基因侧翼区域，遗传距离分别为2.9和3.3 cM。根据已发表的小麦SSR连锁数据，Rht - B2基因被定位到4B染色体长臂上。Rht - B2矮秆基因的这一鉴定和表征将有助于其在小麦育种中的应用。
