^(60)Co-γ射线对三角梅枝条诱变效应的影响

Mutagenic Effect on Branches of Bougainvillea spp.Induced by ^(60) Co-γ Ray

以‘柠檬黄’‘塔橙’和‘樱花’3个三角梅品种的枝条为试材,采用辐射诱变的方法,分别设置10、20、30、40 Gy和50 Gy的辐射剂量,以不辐射(0 Gy)枝条为空白对照(CK),研究了各个品种枝条的成活率,同时针对变异株进行2年的观察,待性状稳定后进行简化基因组测序(GBS),筛选出变异株与对照存在的特异性位点,以期培育出新品种。结果表明:随着辐射剂量增加,3个品种枝条的成活率呈下降趋势,除10 Gy处理下的‘塔橙’以外,其它各处理均显著低于对照;‘柠檬黄’‘塔橙’和‘樱花’辐射耐受范围分别为10~30、10~20 Gy和10~20 Gy,耐受性由强至弱为‘塔橙’>‘柠檬黄’>‘樱花’;3个品种中仅有20 Gy处理下的‘塔橙’发生3种变异症状:变异1叶片呈中卵形,并出现斑叶现象,苞片呈紫红色;变异2苞片呈紫红色;变异3叶片呈窄卵形,苞片呈披针形,颜色偏红,且花被管较突出。经分子鉴定证明,3种变异分别与对照存在234、305个和281个特异性位点。

The branches of‘Golden Glow’‘Pixie Orange’and‘Imperial Delight’were selected as materials,and the survival rate of each variety was determined by using 10,20,30,40 Gy and 50 Gy as radiation dose,and non-radiation(0 Gy)branches as control(CK),in order to breed a new cultivar,we observed the mutants for 2 years and sequenced by GBS after they were stable in character and filtered the specific sites between the mutant and the control.The results showed that the survival rate of branches of three varieties were decreased with increased of radiation dose.All treatments were significantly lower than the control,except for the‘Pixie Orange’treated with 10 Gy.The radiation tolerance of‘Golden Glow’‘Pixie Orange’and‘Imperial Delight’were 10-30,10-20 Gy and 10-20 Gy respectively.The order of radiation tolerance from strong to weak was‘Pixie Orange’>‘Golden Glow’>‘Imperial Delight’.Among the three varieties,only‘Pixie Orange’had three mutants under 20 Gy.In‘mutant 1’,the leaves were ovate and variegated,and the bracts were purplish red.The bracts of‘mutant 2’were purplish red.In‘mutant 3’,the leaves were narrow ovate,the bracts were lanceolate and reddish,and perianth tube was prominent.The results of molecular identification showed that there were 234,305 and 281 specific sites in the three mutants compared with the control,respectively.