质子辐照对金花葵生长发育的影响及其基因组变异的RAPD 分析

对金花葵(Abelmoschus manihot)种子进行不同剂量的质子辐照,并经过种植观察和RAPD分子标记分析,探究辐照对其生长发育的影响.结果显示,辐照剂量为200、500、1000c的金花葵营养生长和生殖生长状况与对照差异显著,但辐照100 c的金花葵变化不明显.其中,辐照剂量为200、500、1000c的金花葵植株明显较对照高,茎秆直径也大于对照,但果实的长、宽均有所减小;每果结籽数有一定增多,但种子的千粒重有一定下降,其中以辐照500、1000c下降较为明显.RAPD分析显示:各辐照处理谱带的分子量集中在200～2 000 bp之间;各辐照处理的DNA基因组均发生了一定变化,出现了条带增多或缺失,以及条带深浅的变化.辐照100、200、500、1000c处理电泳条带与对照间的Nei's遗传距离分别为0.1126、0.2444、0.2081和0.2000.可见,质子辐照能够引起金花葵的基因组发生变化,并表现出植株增高、茎秆变粗、结籽增多、果实变狭长、种子千粒重降低等生物学效应,辐照剂量在200～1000 c时这种诱变效应更明显.

Effects of proton irradiation on growth and development of Abelmoschus manihot and related RAPD analysis of genomic vaiation

In this studythe seeds of Abelmoschus manihot were irradiated with different dose of proton irradiation, then the seeds were planted, observed and analysed by RAPD Randomly Amplified Polymorphic DNA molecular marker assay method to explore the irradiation effects on their growth and development. The results showed that the vegetative growth and reproductive growth of A. manihot which were irradiated by the dose of 200 c 1 c = 4.6 108 protons/cm2), 500 c and 1 000 c was obviously different from that of control group. The plants were significantly higher and their stem diameters were greater than those of control group. The length andwidth of fruits reduced and the seed number of every fruit increased when the seed kernels fell. But thechange with the dose of 100 c was not obvious. The RAPD analysis showed that the molecular weight ofirradiation groups focused on the band between 200 bp to 2 000 bp. The genomic DNA of every irradiatio group changed to a certain degree, with electrophoretic bands increasing or missing, and staining depth changing. The Nei ''s genetic distances of electrophoresis bands between experimental groups(of 100 c, 200 c, 500 c and 1 000 c) and control (based short) were 0.1126, 0.2444, 0.2081 and 0.2000, respectively. The results proved that proton irradiation could cause genomic change of A. manihot and the mutant A. manihot exhibited higher plant, thicker stem, increased seeds, longer and narrower fruit, and lighter seed kernel. The mutagenic effect was more apparent with the irradiation dose of 200-1 000 c.