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The mapping population consisted of 94 F2 generation plants derived from a cross between the CNFC 7812 and CNFC 8056 lines, with different protein contents, 24% and 19% respectively. Seven hundred and fifty-two molecular markers were tested among the parents and four individuals from the segregant population. A total of 101 loci were used to develop the genetic map. The polymorphism rate was 8.3% and 23.2% for the microsatellite and RAPD markers, respectively. The sizes of the linkage groups ranged from 6.7 to 139.0 cM , presenting a mean of 49.4 ± 36.8. The map length was 840.7 cM and the mean group length was 45.9 cM. The average distance between the framework loci was 16.1 cM. This map was compared with international reference bean maps and results were discussed. The construction of the genetic map from parents of the same center of origin and the commercial grain type were discussed. [ABSTRACT FROM AUTHOR]

The genus Oryza comprises 22 species which are potentially useful as a source of genetic variability that can be introgressed into the worldwide cultivated rice, Oryza sativa. Molecular markers are useful tools for monitoring gene introgressions and for detecting polymorphism among species. In this study, cross-amplification was estimated among 28 accessions of 16 Oryza species, representing the genomes AA, BB, CC, BBCC and CCDD, using 59 microsatellite (OG, OS and RM series) and 15 STS (Sequence Tagged Sites) markers. All markers amplified at least one Oryza species, indicating different levels of transferability across species. Markers based on microsatellite sequences amplified 37 % of the accessions, with an average of 6.58 alleles per locus and an average polymorphism information content (PIC) of 70 %. For STS markers, the amplification level was 53.3 %, and the average number of alleles and PIC values were 1.6 and 10 %, respectively. These Results showed that although the STS markers detected a reduced level of genetic diversity, the transferability was higher, indicating that they can be used for genetic analysis when evaluating less genetically related species of Oryza. Among the microsatellite markers, an analysis of species with an AA genome showed that the OG markers produced the highest level of polymorphic loci (54.6 %), followed by RM markers (48 %). Highly polymorphic and transferable molecular markers in Oryza can be useful for exploiting the genetic resources of this genus, for detecting allelic variants in loci associated with important agronomic traits, and for monitoring alleles introgressed from wild relatives to cultivated rice. [ABSTRACT FROM AUTHOR]