QTLs Analysis for Salinity Tolerance at Seedling Stage Using Chromosome Segment Substitution Lines of Dongxiang Common Wild Rice(Oryza rufipogon Griff.)
In our laboratory,we created a chromosome fragment substitution line CSSL91,with high salinity-tolerance,using Dongxiang common wild rice and Nipponbare as parents.In this study,it was compared with Nipponbare and Pokkali,a strong salt-tolerant germplasm,and the results showed that the salt tolerance of CSSL91 was comparable to that of Pokkali.Using the F2∶3 population constructed by CSSL91 and Nipponbare,the phenotypes were normally distributed with salt tolerance grade and seedling survival rate as indicators.QTL linkage location analysis showed that a total of five salinity tolerance-related QTLs were detected,which were distributed on chromosomes 4,9,and 10,with the LOD values ranging from 2.95 to 3.97,and the phenotypic contribution rates ranging from 9.83％to 18.48％.Among that QTL-qST4 is the highest phenotypic contribution in the salt tolerance grade,which was located between DX-C4-1 and DX-S4-16 markers on chromosome 4.Simultaneously,the bulked segregation analysis(BSA)detected a QTL exceeding the threshold value in the interval of 0-5.0 Mb on chromosome 4,which was overlapped with QTL-qST4,indicating that QTL-qSST4 was a reliable salinity tolerance locus;QTL-qST4-1 and QTL-qSSR4 based on salt tolerance grade and seedling survival,respectively,were both located between markers DX-C4-12 and DX-C4-13 on chromosome 4,with LOD values of 3.36 and 3.92,and phenotypic contributions of 13.97％and 9.49％,respectively.Two QTLs based on salt tolerance grades,QTL-qST9 and QTL-qST10,were located on chromosomes 9 and 10,respectively.QTL-qST4-1,QTL-qSSR4 and QTL-qST10 are the new QTLs with salinity tolerance in this study.The results of the present study will lay a foundation for the cloning of salinity tolerance-related genes and molecular markers to assist in the improvement of rice varieties in terms of salt tolerance.
salt tolerant gradeseedling survival ratebulked segregation analysis(BSA)
NETL
NSTL
万方数据
