Wang Y, Bi B, Yuan Q H, Li X L, Gao J M
Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.
Genet Mol Res. 2012 Mar 14;11(1):606-16. doi: 10.4238/2012.March.14.4.
To identify amplified fragment length polymorphism (AFLP) markers associated with resistance or susceptibility of alfalfa to common leafspot (CLS) caused by the fungus Pseudopeziza medicaginis (Dermateaceae), bulked segregant analysis was conducted based on an F(1(M × M)) population of 93 plants and a BC(1)S population of 91 plants. Three AFLP markers, ACTCAA(R206), TAGCAC(R185), and GGACTA(S264), were found to be associated with CLS resistance or susceptibility. All three markers were found at significantly different frequencies (71.9, 80.3 and 91.8%) compared to resistant or susceptible plants in the original population. Subsequently, these three AFLP markers were converted into three SCAR markers, ACTCAA(R136), TAGCAC(R128) and GGACTA(S254), which are easier to employ in breeding programs. The three SCAR markers were used in a randomly selected population with 50% resistance; the probability of finding one resistant plant was increased to 67.3, 66.7 and 90.0% with markers ACTCAA(R136), TAGCAC(R128) and GGACTA(S254), independently. If two of the SCAR markers were used simultaneously, the probability would be higher than 89%. The three SCAR markers identified in this study would be applicable for selection for CLS resistance in alfalfa breeding programs. Moreover, the genetic analysis indicated that CLS resistance in alfalfa is conferred by a single dominant gene.
为了鉴定与苜蓿对由真菌苜蓿假盘菌（盘菌科）引起的普通叶斑病（CLS）的抗性或易感性相关的扩增片段长度多态性（AFLP）标记，基于93株植物的F(1(M × M))群体和91株植物的BC(1)S群体进行了混合分离群体分析。发现三个AFLP标记，ACTCAA(R206)、TAGCAC(R185)和GGACTA(S264)，与CLS抗性或易感性相关。与原始群体中的抗性或易感植物相比，这三个标记在频率上存在显著差异（分别为71.9%、80.3%和91.8%）。随后，这三个AFLP标记被转化为三个序列特征扩增区域（SCAR）标记，ACTCAA(R136)、TAGCAC(R128)和GGACTA(S254)，它们在育种计划中更易于应用。这三个SCAR标记被用于一个抗性比例为50%的随机选择群体；使用标记ACTCAA(R136)、TAGCAC(R128)和GGACTA(S254)时，独立发现一株抗性植物的概率分别提高到67.3%、66.7%和90.0%。如果同时使用两个SCAR标记，概率将高于89%。本研究中鉴定的这三个SCAR标记可应用于苜蓿育种计划中CLS抗性的选择。此外，遗传分析表明苜蓿对CLS的抗性由一个单显性基因控制。
