优质四倍体萝卜新种质创新及鉴定

[目的]对秋水仙素诱导同源四倍体苗期性状进行筛选,提高加倍率,为市场提供更优质高产四倍体萝卜。[方法]以二倍体萝卜‘小顶红’为材料,用1.5、2.0和2.5 g？L-1秋水仙素点滴子叶期生长点,分别处理4次和6次,拉十字期时对叶片响应进行形态分类、形态解剖学和流式细胞仪鉴定,测定二、四倍体农艺性状、肉质根营养成分,以及二、四倍体‘小顶红’和‘穿心红’种子发芽相关物质。[结果]2.0 g？L-1秋水仙素处理4次获得的四倍体植株加倍率最高,为4.76%。幼苗真叶响应形态可分为正常叶、簇状叶、棒状叶和勺状叶,簇状叶类型当代选株中四倍体加倍率最高,占88.24%。与二倍体相比,四倍体的气孔、花粉粒、花器官、叶片和肉质根等表现出明显的"巨大性",但气孔密度、单果种子数量显著减少。四倍体萝卜肉质根的可溶性糖、可溶性蛋白和维生素C含量分别比二倍体增加23.50%、12.24%和27.36%。经两代选育,四倍体纯度达95%,增产20.21%。四倍体种子的可溶性糖含量、可溶性蛋白含量、脱氢酶活性均较对应二倍体高。[结论]早期选择簇状叶可提高加倍率,经继代选育后,获得纯度较高的四倍体萝卜株系。
[Objectives]Colchicine filtered induction autotetraploid seedling traits,increased the rate of doubling and provided the market with high quality of new germplasm autotetraploid radish. [Methods]The diploid radish(Raphanus sativus L.)‘Xiaodinghong’was induced by treating the apical portion of cotyledon with colchicine solution by 1.5,2.0 and 2.5 g？L-1,drip 4 and 6 time,respectively. At two true leaves stage,the morphological classification of leaves was performed. Morphology and anatomy and flow cytometry were used to identify the autotetraploid radish. Agronomic traits,fleshy root nutrition ingredient and germination-related contents of diploid and autotetraploid radish‘Xiaodinghong’and‘Chuanxinhong’seed were measured. [Results]The result showed that the highest mutation rate of treatment group was obtained with 2.5 g？L-1 colchicine solution for 4 times,the highest double rate of treatment group was obtained with 2.0 g？L-1 colchicine solution for 4 times,and the frequency was 4.76%. After colchicine treatment,seedling morphologies were aberrant. The seeding leaf response was divided into normal character,clustered character,virgate character and scoop character,and the highest rate was clustered character and the frequency was 88.24%. Until harvest time,stomata,pollen grain,flowers,leaves and root of the autotetraploid plants showed the"enormous characteristic". Compared with diploid plants,stomatal density in single field of view and number of seeds in single pod showed significant reduction. The contents of soluble protein,soluble sugar and vitamin C in atuotetraploid radish fleshy root were increased 23.50%,12.24% and 27.36%,respectively. After two generation of breeding,autotetraploid purity was 95%,and production increased 20.21%. For auto-tetraploid‘Xiaodinghong’,compared with diploid radish seed,content of soluble protein,soluble sugar and dehydrogenase activty efficiency increased,respectively. [Conclusions]Choosing clustered character could improve the double rate,and after continuous progeny selection,we obtained high-quality new autotetraploid