水稻耐淹涝性状的遗传分析和SSR标记的研究

淹涝胁迫对水稻生产造成了严重影响, 发掘可应用于耐淹涝辅助选择的分子标记(MAS), 将有助于水稻耐淹涝性状的遗传改良。应用耐淹涝材料FR13A和淹涝敏感材料IR39595-503-2-1-2为亲本做正反交获得F₁和F₂代群体。对正反交的F₁群体的耐淹涝性状进行遗传分析, 发现正反交的F₁代群体在耐淹涝性状上没有显著差异, 说明耐淹涝性状是核基因控制。从两次淹涝处理中F₂代群体的分离情况来看, 来源于FR13A的耐淹特性表现出数量-质量性状遗传的特点。当淹涝胁迫压力比较轻时表现为数量性状遗传, 具有微效多基因的作用。当淹涝胁迫压力增大时, 表现为主效基因控制的质量性状。在SSR分析中, 187对SSR引物中有73对引物在两亲本间有明显的差异, 差异率为39%。用这73对差异引物, 对F2群体进行多态筛选, 结果筛选到一个与耐淹涝性状连锁的标记RM219, 验证了耐淹涝性状确实由主效基因Sub1控制, 因此, RM219在水稻耐淹涝育种中具有利用价值。

Genetic Analysis and SSR Marker of Tolerance to Submergence in Rice

Submergence stress has severe harm to rice (Oryza sativa L.) production. It is important to identify molecular markers associated with tolerance to submergence for marker-assisted selection (MAS). F1 and F2 populations ware obtained from reciprocal crosses between submergence tolerant parent FR13A and submergence sensitive parent IR39595-503-2-1-2. No difference in reciprocal crosses in F1 population was detected for tolerance to submergence. This indicates that the submergence character is controlled by nucleic factor(s). Tolerance to submergence derived from FR13A appeared to be a quantitative-qualitative trait as revealed by the segregation of F2 population in two submergent experiments. Under light submergence stress, multiple minor genes might work and the trait inherited quantitatively it appeared a quantity trait, While under severe submergence stress, it exhibited a qualitative inheritance controlled by a major gene. Among the 187 pairs of SSR primers, 73 (39%) were polymorphic between the two parents and were used to tag submergence in the F2 population. Primer RM219 was detected to be linked to submergence tolerant trait loci. This result confirmed that tolerance to submergence is controlled by the major gene sub1, which will be helpful in improvement of the trait in rice.