棱角山矾叶型变异分析与变异类型的分子甄别

Analysis of leaf shape variation and molecular screening of variation types in Symplocos tetragona

本研究以研究组初步筛选的4个编号I-IV的棱角山矾叶型变异类型为研究对象,开展其叶型变异分析及基于ISSR分子标记的变异类型分子甄别。叶型变异分析表明,4个类型的叶长、叶宽尺度均呈现Ⅰ型<Ⅱ型<Ⅲ型<Ⅳ型趋势。Ⅰ型与Ⅱ型的叶型指数数值相近,这与两者具有相似的叶片形状一致。Ⅰ型叶型指数变异系数最小(7.57),同时叶长与叶宽显著相关(r=0.908,p<0.01),说明该类型叶片生长过程中长与宽的扩展速度相对一致。变异类型的ISSR分子甄别显示4个类型的基因多样度为0.2562。利用UBC843、UBC848及UBC8453个分子标记可一次性鉴别4个类型。亲缘关系分析显示,Ⅰ型与其他3个类型的亲缘关系最远,Ⅲ型与Ⅳ型亲缘关系最近;采用UPGMA法按遗传距离进行聚类,属于小叶型的棱角山矾Ⅰ型与Ⅱ型聚成一类,与大叶型的Ⅲ型与Ⅳ型成组分离,这与4个类型的表型表现一致。综合表型与分子数据,Ⅰ型可进一步作为棱角山矾小叶型品种进行培育。

The analysis of leaf shape variation and molecular screening of variation types based on ISSR （inter-simple sequence repeat） molecular marker for four leaf type variation numbered type I-IV of Symplocos tetragona was carried out in this study. The 4 types had a trend to elongate their leaves＇ length and width followed by type I〈 type II 〈 type III 〈 type IV. The leaf shape index values of type I and type II are similar, which is similar to both of the same blade shape. The variation coefficient of leaf shape index of type I was the smallest （7.57）, and the leaf length and leaf width were significantly correlated （r=0.908, p〈0.01）, which is showed that the length and width of the growth process of this type of leaf blade are relatively uniform. Variant type of ISSR molecular screening showed genetic diversity of 4 types was 0.2562. Using three molecular markers of UBC843, UBC848 and UBC845, 4 types could be identified. The relationship analysis for 4 types showed that type I was farthest to the other three, while types III was most similar to type IV. Using UPGMA （unweighted pair group method using arithmetic averages） method, type I and type II can be clustered in one group, and type III and type IV can be clustered in another. It was according with the relative morphologies of the 4 types. Comprehensive phenotypic and molecular data, type I as a type of lobular type varieties could be cultivated.