Detection the ploidy levels in asiatic lily cross-breeding through karyotype analysis and fish

摘要

Conventional hybrid breeding methods were used to hybridize and evaluate the affinity of different ploids lily varieties as parents, and abundant hybrid offspring were obtained by embryo rescue. The karyotype analysis and 45S rDNA-based fluorescence in situ hybridization (FISH) were applied to identify the lily chromosomes. The genetic variation of chromosomes between progenies was analyzed and the 45S rDNA distribution was analyzed. It was found that the parental ploidy had some influence on the hybridization affinity. Diploid and tetraploid interploidy hybridization (Intraploidy hybridization) was stronger than between different ploidy hybridization (Interploidy hybridization). Triploid lily could be used as a successful female with diploid or tetraploid and 3x×4x hybridization was easier to hybridize than 3x×2x. The chromosome ploidy of Asian lily was rich in diploid, triploid, and tetraploid. The 45S rDNA signal loci of lily were usually not in pairs but increased with the ploidy of chromosome. Asian lily varieties had a pair of chromosomes on chromosome 1, which could be used as the characteristics of Asian lilies. The hybrid chromosomes were identified by the hybridization progenies by hybridization with FISH. The chromosomes were identified as true hybrids from all parents, and there were differences between different genotypes of hybrid progeny. Karyotype combined with fluorescence in situ hybridization could trace the origin of characteristic chromosomes in hybrid progeny, and identify hybrid authentically quickly and effectively.