[Objective] This study aimed to investigate the functions and properties of the preliminarily determined characteristics listed in DUS test guideline of Tagetes L., and explore the representativeness and comprehensiveness of this group of characteristics in DUS test. [Method] Based on the functions and properties of the characteristics, the described plant part (s), observation stage, expression pattern and observation method of each characteristic were analyzed to illustrate the representativeness and comprehensiveness of the combination of this group of characteristics in above functions and properties. [Result] As for described plant part(s), there are 5 characteristics describing plant as a whole, 3 characteristics describing stem, 6 characteristics describing leaf, 23 characteristics describing flower and 1 characteristic describing physiological feature. As for observation stage, there are 1 characteristic needing to be observed in the stage of seedling, 1 characteristic in the stage of beginning of flowering and other 36 characteristics in the stage of fully flowering. As for the expression pattern, there are 10 qualitative characteristics, 9 pseudo-qualitative characteristics and 19 quantitative characteristics. As for the observation method, there are 30 characteristics using VG as the observation method, and 8 characteristics using MS. [Conclusion] In view of the variation and morphological properties of marigold, this group of characteristics are representative and comprehensive, and ensure the accuracy and easiness of DUS test of Tagetes L., thereby achieving the reasonable combination of characteristics in described plant parts, observation stages, expression patterns and observation methods.
【目的】对107个云南玉米自交系进行遗传多样性和群体遗传结构分析,为云南省玉米种质创新、遗传改良、品种管理等提供理论依据,也为今后深入挖掘优良性状相关基因打下基础。【方法】以云南当地推广的107个优良玉米自交系为供试材料,以45个我国常用玉米骨干自交系作为杂种优势群划分的参照,在Axiom~?Maize56K SNP Array平台上利用玉米SNP芯片(56K)进行玉米全基因组扫描,并使用Treebest的NJ-tree模型构建系统发育进化树,利用GCTA(全基因组复杂性状分析)工具进行主成分分析,揭示其遗传多样性与群体遗传结构。【结果】从107个云南玉米自交系中检出5533个均匀分布的高质量SNP分子标记位点。基于这些SNP分子标记位点分析结果可知,107个云南玉米自交系的Nei’s基因多样性指数(H)为0.2981~0.5000,平均为0.4832;多态信息含量(PIC)为0.2536~0.3750,平均为0.3662;最小等位基因频率为0.5000~0.8178,平均为0.5744。群体遗传结构分析结果显示,K=6时△K最大即供试自交系可划分为六大类群,分别为塘四平头血缘类群、PB血缘类群、335母本血缘类群、自330和旅大红骨血缘类群及2个未知类群,无自交系划分到其他杂交优势群,其中,2个未知类群共37个云南玉米自交系,未能与我国目前已知的10个杂种优势群归在一类。主成分分析结果显示,107个云南玉米自交系与45个我国常用玉米骨干自交系能明显区分,大部分云南玉米自交系集中在我国常用玉米骨干自交系附近,但少数云南玉米自交系与我国常用玉米骨干自交系距离较远。【结论】云南地区玉米种质资源遗传多样性较丰富,含有多个杂种优势群,育种亲本遗传基础丰富,与我国常用玉米骨干自交系能明显区分,且部分与骨干自交系遗传距离较远,可创建新的杂交优势群,具有良好的应用潜力。