Identification of introgressed alien chromosome segments associated with grain quality in Oryza rufipogon x MR219 advanced breeding lines using SSR markers.
A limited backcross procedure was utilized to  introgress genes associated with grain quality traits from Oryza rufipogon (Accession  No. IRGC 105491), a wild rice from Malaysia, to the cultivated rice O.  sativa cv. MR219, a popular high yielding Malaysian rice cultivar. A set of  10 BC(2)F(7) progenies were selected based on the field performance  and phenotypic appearance in BC(2)F(5) and BC(2)F(6) generations, which initially started with 266  progenies in the BC(2)F(2) generation. These 10 advanced breeding lines are  similar to each other but differ in several important grain quality traits,  which can be traced to O. rufipogon introgressions. Phenotyping and  genotyping of BC(2)F(7) variants were considered for QTL analysis. The  introgressed lines did not show any significant changes compared to the  recurrent parent MR219 for the traits grain density and milled rice percentage.  All 10 progenies showed significantly higher head rice percentages (70-88%)  than the recurrent parent MR219. Variants G13 and G15 had higher amylose  contents than MR219. All variants were analyzed using polymorphic SSR markers.  Of the 34 SSR markers, only 18 showed introgression from O. rufipogon for  chromosomes 1, 2, 3, 5, 6, 8, 10, and 11. Graphical genotypes were prepared for  each variant, and association between the introgression regions and the traits  that increased grain quality was visualized. Based on marker trait association,  some of the QTLs are stable across environments and genetic backgrounds and  could be used universally.
School of Environmental and Natural Resource Sciences, National University of Malaysia, Kuala Lumpur, Malaysia.
P
P
Fasahat
K
K
Muhammad
A
A
Abdullah
R
R
Wickneswari
D032461:Chromosomes, Plant / Q000235:genetics*; D003433:Crosses, Genetic; D005819:Genetic Markers; D005838:Genotype; D007178:Inbreeding; D018895:Microsatellite Repeats / Q000235:genetics*; D012275:Oryza / Q000235:genetics*; D011110:Polymorphism, Genetic; D012639:Seeds / Q000235:genetics*
D005819:Genetic Markers