Cytogenetic Analysis of Asiatic Lily Cultivars and Their Hybrids Using Fluorescence In Situ Hybridization

Two Asiatic lily cultivars, 'Golden Horn', 'Pollyanna', and their six progenies were analyzed using Fluorescence in situ hybridization (FISH) with 45S rDNA as probe. It was shown that five progenies were diploid (2n=2x=24), one progeny was triploid (2n=3x=36), We observed a total of 11 hybridization signals on chromosome No 1, 2, 3, 4, 7 and 11 in 'Golden Horn', 10 hybridization signals occurred on chromosome No 1, 2, 4, 6, 7 and 11 in 'Pollyanna'. 45S rDNA loci were variable on chromosome No 3 and 6 of these two cultivars. Chromosome No 3 in 'Golden Horn' contained two 45S rDNA loci which were observed at the centromere and long arm, while 45S rDNA locus on chromosome No 6 in 'Pollyanna' was on the long arm. In addition, 45S rDNA loci on chromosome No 1 and 7 were located near the centromere, on chromosome No 2 the signals were near the secondary constriction and on chromosome No 4 and 11 were on the long arm. There were either 9 or 11 45S rDNA loci in the five diploid hybrids, and there were 15 loci in the triploid progeny. FISH detection of 45S rDNA clearly showed that all 45S rDNA signals in four progenies (GHP16, GHP142, GHP223, GHP245) were coming from 'Golden Horn' and 'Pollyanna', respectively.