离子注入后同源四倍体多胚苗突变水稻的筛选及其遗传稳定性

以低能氮离子束为诱变源,对同源四倍体水稻品系“IR36-4X”进行离子注入,在其第2代群体内筛选得到了1株具有多胚苗性状特征的突变株(IR36-双)。对该突变株后代的主要农艺性状、多胚苗形态特征和遗传稳定性进行研究表明,突变株系与其原始亲本在主要农艺性状上存在明显差异,前者在株高、穗长、千粒重和结实率等性状上比后者分别下降35.41%、5.08%、15.72%和12.39%。“IR36-双”在双胚苗性状的表现形态上有其特异性,在同一纯合株系的群体内双胚苗的苗位有非完全双苗和完全双苗两种类型。在非完全双苗中又包括单胚轴单胚根双苗和单胚根异胚轴双苗;在完全双苗中可分为正常双苗和异常双苗。在多胚苗材料中,单胚根单胚轴双苗所占的比例相对较大。经过多个世代观察表明,“IR36-双”的多胚苗特性表现出明显的可遗传性。

DEVELOPMENT AND CHARACTER OBSERVATION OF AUTOTETRAPLOID POLYEMBRYONIC MUTANT RICE INDUCED BY ION BEAM IMPLANTATIOON

Autotetraploid rice IR36-4X was treated with ion implantation of low energy nitrogen ion beams and a polyembryonic seedling mutant IR36-Shuang was identified in M_2 generation.The major agronomic characters,morphology and the genetic stability of polyembryonic seedling of the mutant line were systematically investigated.The results are as follows.The agronomic characters of IR36-Shuang were obvious different with its parent IR36-4X.The plant height,panicle length,1000 grain weight and the setting rate of the IR36-Shuang were lower than that of its parent by 35.41%、5.08%、15.72% and 12.39%,respectively.The morphology of polyembryonic rice IR36-Shuang could be differentiated into 2 types: uncomplete twin seedlings and complete twin seedlings.There were 2 types in uncomplete twin seedlings,i.e.twin seedlings with single plumule axis and single radicle and twin seedlings with single radicle and twin plumule axis.The complete twin seedlings also included 2 types,i.e.normal and abnormal twin seedlings.In IR36-Shuang materials,the rate of twin seedlings with single radicle and single plumule axis was higher than that in other types.The several generations observation showed that the polyembryonic trait was inherited and stable.