Characterization and genetic analysis of near-isogenic lines of common wheat for awn-inhibitor gene | 小麦芒长抑制基因B1近等基因系的鉴定及遗传分析

Chinese. 芒是小麦穗部重要的光合器官之一。本研究以一对芒长度存在差异的近等基因系SN051-1（长芒）与SN051-2（短芒）为材料,对其形态性状、穗和旗叶光合能力进行了调查,对芒长性状进行了遗传分析和分子标记分析。结果表明,SN051-1与SN051-2在抽穗期、开花期、株高、穗长、每株穗数、小穗数和穗粒数等性状方面均表现一致,仅芒的长度差异明显;SN051-1穗部的光合效率高于SN051-2穗部的光合效率,其千粒重也高于SN051-2;遗传分析证明二者芒性的遗传由单基因控制,短芒为显性。此外,我们筛选获得一个与芒长性状紧密连锁的、位于5A染色体长臂的SSR标记Xgwm291,与该基因间的遗传距离为4.99cM。因此,我们初步推断SN051-1与SN051-2可能是为位于5A染色体长臂的芒抑制基因B1的近等基因系。[著者文摘]

English. Awn is one of the major photosynthetic organ of wheat ear. In this study, near-isogenic lines of common wheat with different awn length, SN051-1 （long awns） and SN051-2 （short awns）, were investigated on morphological traits and photosynthetic abilities of wheat ear and flag leaf, genetic analysis and molecular marker identification for the awn trait were also carried out. The results showed that the two lines had no obvious difference in the observed traits, which including heading date, flowering period, plant height, spike length, spike number per plant, spikelet number per spike and kernel number per spike except the traits of awn leagth and thousand kernel weight The further results demonstrated that the photosynthetic rate of the wheat ear of SN051-1 was higher than that of SN051-2, which presented the same trend of the thousand kernel weight. Genetic analysis revealed that the awn length of the tested lines might be controlled by single-locus, and the trait of short awn should be dominant trait. In this research we also identified an SSR marker, Xgwm291, linked with the locus controlling the length of awn and mapped on the long arms of 5A chromosome with the distance of 4.99 cM from the known awn-inhibitor gene B1, and consequently we may have an elementary conclusion that the lines of SN051-1 and SN051-2 could have allele conferring the awn-inhibitor gene B1.[著者文摘]