Development and molecular characterization of a doubled haploid population derived from a hybrid between rice and wide compatible rice.

Doubled haploid (DH) populations, particularly those from subspecies crosses possessing the wide compatible gene , are important germplasm resources for rice genetic studies and breeding, but their feature and potential have not been fully assessed and explored. In the present study, we produced a DH population from the hybrid of 668B and wide compatible T23. Genotyping of the locus with allele-specific markers for , and revealed a potential recombination hot spot in the region. Haplotyping analysis revealed that 21/34 subspecies specific Indel markers segregated in distortion in the DH population, with a few lines having alleles either extremely low (1.7%) or high (98.3%), with little effect of the allele. While DH lines with the allele had higher frequency of alleles, no effect of the allele was observed on all agronomic traits but flowering time. Taken together, the present study advanced understanding of the genetics of wide crosses in general, and DH production in particular between the two rice subspecies, and the new DH population generated will become a useful resource for rice genetic study and breeding in the future.