航天诱变凤仙花嵌合突变体（SP2）的形态及减数分裂的观察

在航天诱变凤仙花的SP2代中，得到一株枝叶嵌合突变体．该嵌合突变体的两类枝条在许多性状存在明显差异．突变枝条的减数分裂严重异常，而正常枝条的减数分裂受突变枝生长情况的影响而表现不同程度的异常．本文对嵌合突变体正常枝的性状恢复的可能原因进行了分析，认为原突变株多个性状的改变可能是控制枝叶，花器发生以及减数分裂代谢途径的上游基因发生了突变而表现的基因多效性，而嵌合体上正常枝条性状的恢复可能是由基因的回复突变造成的．

Observation of Morphological Characters and Meiosis on Chimera Mutant (SP2) Induced by Space Flight in Impatiens balsamina

A chimera mutant in generation SP_2 induced by space flight of Impatiens balsamina is obtained, and its traits and meiosis are investigated. There are apparent differences between the two branches and leaves of chimera mutant I_(7-1-1). Meiosis of mutation branch is abnormal. The degree of abnormal meiosis of normal branch is affected by the mutation branch, especially by the development of the mutntion branch. The reason of the normal branch of chimera mutant developed from abnormal branch is analysis, and it is thought that the change of characters of the preceding mutant is ascribed to the mutation of epistatic gene controlling differentiation of branch and leave, along with meiotic behavior. The resumed normal branch is probably due to back mutation of the epistatic gene.