从T-DNA突变体库中获得一份以中花11为遗传背景的白色中脉突变体。该突变体剑叶以下叶片的中下部中脉表现为白色, 白色中脉附近的叶色微黄, 并且伴随株高等农艺性状的改变, 暂时将其定名为Oswm2(Oryza sativa white midrib 2)。遗传分析表明该突变性状受一对隐性单基因控制, 以Oswm2和粳稻02428杂交的F2分离群体作为定位群体, 将OsWM2基因定位在水稻第7染色体的SSR标记RM21478和RM418之间, 遗传距离分别为8.7和15.9 cM。

A rice (Oryza sativa L.) plant with white midrib (Oswm2) was selected from the T-DNA inserted mutant pool of rice. The basal midrib of the leaves in the mutant, except for the flag leaves, is white. The blade close to the white midrib is etiolated, and alterations of the agronomic traits, such as plant height, panicle length occur in the mutant. Genetic analysis indicated that this mutant trait was controlled by a recessive nuclear gene. To map the OsWM2 gene, an F2 population was constructed by crossing mutant Oswm2 with 02428. The OsWM2 locus was preliminarily located between the SSR molecular markers RM21478 and RM418 on chromosome 7 with the distances of 8.7 and 15.9 cM, respectively.