四倍体小麦背景中长穗偃麦草E染色体传递特征

Transmitting characters of individual E chromosomes of Thinopyrum elongatum in Triticum turgidum background

通过细胞学方法和染色体特异分子标记鉴定六倍体小偃麦(AABBEE)与硬粒小麦(AABB)杂交的自交后代F_2和F_3植株,探讨长穗偃麦草染色体在硬粒小麦背景中世代间的传递特征,并筛选硬粒小麦-长穗偃麦草E染色体附加系。对218个F2单株染色体数检测表明,2n=28植株占41.7%,2n=29植株占18.3%,其余40.0%植株的染色体数在2n=31~42范围内。分子标记鉴定表明,在F_2代2n=29单体附加植株中,不同的长穗偃麦草染色体传递率之间存在明显差异,1E传递率最高,3E和6E传递率最低。在F_2代2n=30单株中,1E、4E、7E和5E染色体相互组合产生的双单体多,6E参与组合较少,未检测到2E或3E与其他染色体的组合单株。在1E^7E单体附加株自交后代F_3中,E染色体传递率变化范围为9.1%~27.5%,1E传递率最高,6E传递率最低,与F2的传递率一致。从F3代中选育出1E^7E单体附加及少数二体附加,所有单体附加均可育。这些附加E染色体材料将对小麦代换系和易位系的创制提供有益的中间材料。

The transmission patterns of Thinopyrum elongatum chromosomes in the background of Triticum turgidum were investigated through cytogenetic and molecular marker analysis based on the F2 and F3 plants derived from a cross between Triticum trititrigia （AABBEE） and T. turgidum L. ssp. durum （AABB）. An additional objective was to develop durum-Th. elongatum E chromosome addition lines. Among 218 F2 plants, individuals with 2n=28 accounted for 41.7%, those with 2n=29 accounted for 18.3%, and the remaining 40.0% had 2n=31-42. Molecular marker analysis of the F2 monosomic addition plants with 2n=29 showed significant differences in transmission rate among Th. elongatum chromosomes. Chromosome 1E had the highest transmission rates, while 3E and 6E had the lowest. Among F2 double monosomic addition plants with 2n=30, joint transmission was frequent between 1E, 4E, 7E and 5E;6E was less frequent in joint transmission with other chromosomes, while 2E and 3E never transmitted along with other chromosomes. Among F3 plants derived from F2 monosomic addition plants, the transmission rates of E chromosomes varied widely, from the minimum of 9.1% for 6E to the maximum of 27.5% for 1E, consistent with observations from F2 plants. A full set of durum-Th. elongatum 1E-7E monosomic addition lines and several disomic addition lines were selected from F3 plants, and all monosomic addition plants were fertile. These chromosome E addition lines will be useful intermediate materials for developing substitution lines and translocation lines.