基于SSR标记的宁夏水稻遗传多样性分析

Analysis of Genetic Diversity with Population of Japonica Rice from Ningxia Using Microsatellite Markers

选择自20世纪80年代以来的59份宁夏水稻种质，利用分布于12条染色体上的82对SSR引物进行遗传多样性和遗传相似性分析。共检测到339个等位基因，品种间不同位点等位基N数目2～19个，平均4．13个。Nei’s基因多样性指数变幅为0．0333～0．9164，平均为0．4394。按种质释放或审定年代，将其中的55份水稻分为3个群体，随着年代的增加，等位基因数和遗传多样性指数均呈增大趋势，且3个群体间等位基N数和多样性指数差异均达极显著水平（P〈0．01）。UPGMA聚类分析表明，参试59份水稻种质在遗传相似系数0．78水平上聚为5大类，其中第1类为1份香稻种质；第Ⅱ、Ⅳ类均为3份种质；第1I类有5份种质，与吉林水稻相似；绝大多数品种被聚为第V类，占参试材料数的79．7％。对比宁夏水稻选育品种系谱，大多数种质具有宁夏骨干亲本红旗12号、京引39号、东方红2号、京引59号等的血缘，种质间亲缘关系较近。虽然近年来宁夏水稻的遗传多样性有增加的趋势，但遗传基础狭窄，参试种质的遗传相似系数在0．70以上，最高达0．97。应继续加大力度引进和创新亲本材料，拓宽宁夏水稻的遗传基础。

A total of 82 SSR markers distributed on 12 chromosomes were used to analyze genetic diversity and genetic similarity in 59 rice varieties of Ningxia province after 1980s. 339 alleles were revealed,and 2 to 19 alleles were identified among different loci. The mean number of alleles per locus was 4. 13. Total Nei＇s genetic diversity index varied greatly from 0. 0333 to 0. 9164,with an average of 0. 4394. The 55 rice varieties were divided into 3 groups according to their released years. With the increase of the year, both the number of alleles and genetic diver- sity showed an significant increasing trend （P 〈 0.01 ）. UPGMA cluster analysis showed that the 59 rice varieties were cluster into five categories at the genetic similarity coefficient of 0.78. The category I had only one aromatic rice, 11 and IV both had three varieties, and category Ⅲ contained five varieties similar to Jilin rice. The most rice varieties were clustered into category V ,which accounted for 79.7% of the tested varieties. Compared the pedigree of riee varieties,the vast major varieties had kinship of Ningxia core parental such as Hongqi 12,Jingyin 39, Dong- fanghong 2, Jingyin 59, etc, which showed close relationship among varieties. Although the genetic diversity of Ningxia rice had increased in recent years, the genetic basis was still narrow. The similarity coefficient of the tested varieties was above 0. 70, even as high as 0.97. Breeders must introduce and innovate more parental materials in or- der to expand the genetic foundation of Ningxia rice in the future.