利用SSR标记揭示中国粳稻地方品种遗传多样性

【目的】通过中国粳稻地方品种的遗传多样性分析,阐明各省份粳稻地方品种的遗传结构及其亲缘关系,为中国粳稻杂交育种的亲本选配提供科学依据。【方法】利用43对SSR多态性标记,对原产于中国17个省(市、自治区)的187份粳稻地方品种进行等位基因多样性、遗传结构和聚类分析。【结果】共检测到等位基因351个,每个位点等位基因变幅为2—21,平均每个位点等位基因数为8.2;基因多样性指数变异范围为0.117—0.908,平均为0.550;多态信息含量(PIC)变异范围为0.114—0.902,平均为0.523。在RM72、RM241、RM219、RM412和RM232等位点所检测到的遗传多样性参数值较大。西南、华南、华中粳稻地方品种的遗传多样性明显高于华北和东北地区;云南省粳稻地方品种遗传多样性最丰富,天津和吉林的粳稻地方品种的遗传多样性相对较低。基于Nei’s遗传距离的系统聚类把供试材料分为8个小类群,南方粳稻地方品种主要聚类于第ⅰ、ⅱ、ⅲ、ⅳ和ⅴ等5个小类群,北方粳稻地方品种主要聚类于第ⅵ、ⅶ和ⅷ等3个小类群。基于模型的群体结构分析,供试材料被分为11个亚群,有144份材料被分到相应的11个亚群,其余43份材料被分到混合亚群。【结论】南方稻区粳稻地方品种的遗传多样性明显高于北方稻区,其中西南稻区的粳稻地方品种遗传多样性最为丰富,而云南是粳稻地方品种遗传多样性最丰富的省份。北方与南方粳稻地方品种间存在较大的遗传差异,粳稻地方品种间亲缘关系与地域性存在一定的相关性,这种相关性在北方粳稻地方品种中更为突出。RM72、RM241、RM219、RM412和RM232适合应用于粳稻地方品种的遗传多样性检测。

Analysis of Genetic Diversity of Japonica Rice Landrace in China with Microsatellite Marker

【Objective】 The objective of this study is to analyze the genetic diversity,genetic structure and genetic relationship of japonica rice landrace from China,and to provide effective information for hybrid breeding of japonica rice.【Method】 The genetic diversity,genetic structure and cluster analysis of 187 japonica rice landraces from 17 provinces(cities or municipalities) of China were discussed using 43 pairs of polymorphic SSR markers.【Result】The total number of alleles detected from all tested 187 accessions was 351,and the alleles per locus ranged from 2 to 21 with the mean value of 8.2.The Nei’s gene diversity indices varied from 0.117 to 0.908 with an average of 0.550.The polymorphism information content(PIC) was changed from 0.114 to 0.902 with the average of 0.523.RM72,RM241,RM219,RM412 and RM232 showed higher genetic diversity than the others.The gene diversity values(He) of japonica rice landrace from southwestern,south and central China were higher than that of north and northeastern China.The He of japonica rice landrace from Yunnan was highest compared to the other provinces,while the lowest were Tianjin and Jilin.The dendrogram of japonica rice landrace was constructed based on Nei’s genetic distance,showed that all rice varieties were subdivided into 8 clusters.The japonica rice landrace of south China contained ⅰ,ⅱ,ⅲ,ⅳ and ⅴ clusters,the north China consisted of ⅵ,ⅶ and ⅷ clusters.The genetic structure analysis was performed based on model,the japonica rice landrace was divided into 11 subgroups including 144 individuals and a mixed group comprising of 43 individuals.【Conclusion】Compared to north rice region,the south rice region showed significantly higher genetic diversity,and genetic diversity in Southwestern China of rice cropping region was the most among the 5 regions,and the center of origin of Chinese japonica rice landrace is probably Yunnan province.The japonica rice landrace from north and south was largely divergent,and the genetic relationship among japonica rice landrace was partly correlated with the geographical distribution,especially in north japonica rice region.RM72,RM241,RM219,RM412 and RM232 were fit for assessment of the genetic diversity of japonica rice landrace.