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Lilium, an important ornamental crop, requires genetic and phenotypic assessment in the development of new hybrids. Therefore, genetic (using FISH) and morphological studies were conducted on newly developed hybrids belonging to Lilium genomes (Asiatic, Oriental, longiflorum). Morphological results revealed that all F1 hybrids showed significant differences from one another. Triploid Asiatic hybrids (Brunello × Mapira) showed good phenotypic characteristics and longiflorum hybrids (Bright Tower × Snow Queen) expressed good growth characters. The Brunello × Mapira hybrid was especially superior in root length, number of scales, bulb diameter and bulb weight. Chromosomal studies confirmed that all hybrids were diploid (2x = 24) with 24 chromosomes except the "AA-2" Asiatic hybrid which was triploid (2x = 3x = 36). In our karyotyping results, there was non-significant variation with respect to short arm length and arm length ratio among hybrids, while long arm length and total chromosome length showed significant differences. In the case of 45S signals, the maximum number of 45S rDNAs were found in "Bright Tower × Snow Queen" while the minimum number of 45S signals (2) were found in "Yellow cocotte × Valdisole". 5S signals were similar in all hybrids except triploid Asiatic hybrids. Thus, newly developed young hybrids can be successfully screened using morphological and FISH analysis. FISH karyotyping identified a triploid Asiatic hybrid which was also superior in phenotypic characteristics. [ABSTRACT FROM AUTHOR]

Self-fertilization (also termed selfing) is a mode of reproduction that occurs in hermaphrodites and has evolved several times in various plant and animal species. A transition from outbreeding to selfing in hermaphroditic flowers is typically associated with changes in flower morphology and functionality. This study aimed to identify genetic effects of selfing in the F2 progeny of F1 hybrid developed by crossing Lilium lancifolium with the Asiatic Lilium hybrid 'Dreamland.' Fluorescence in situ hybridization (FISH) and inter-simple sequence repeats (ISSR) techniques were used to detect genetic variations in plants produced by selfing. The FISH results showed that F1 hybrid were similar to the female parent (L. lancifolium) regarding the 45S loci, but F2 individuals showed variation in the number and location of the respective loci. In F2 progeny, F2-2, F2-3, F2-4, F2-5, and F2-8 hybrids expressed two strong and one weak 5S signal on chromosome 3, whereas F2-7 and F2-9 individuals expressed one strong and two weak signals. Only two strong 5S signals were detected in an F2-1 plant. The ISSR results showed a maximum similarity value of 0.6269 between the female parent and the F2-2 hybrid. Regarding similarity to the male parent, a maximum value of 0.6119 was found in the F2-1 and F2-2 hybrids. The highest genetic distance from L. lancifolium and the Asiatic Lilium hybrid 'Dreamland' was observed in the F2-4 progeny (0.6352 and 0.7547, respectively). Phylogenetic relationships showed that the F2 progeny were closer to the male parent than to the female parent. Self-fertilization showed effects on variation among the F2 progeny, and effects on the genome were confirmed using FISH and ISSR analyses. [ABSTRACT FROM AUTHOR]

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Species of the genus Lilium are well known for their large genomes. Although expansion of noncoding repeated DNA is believed to account for this genome size, retroelement del Ty3- gypsy is the only one described so far in the genus Lilium. We isolated Ty1- copia elements from Lilium longiflorum and named them LIREs (lily retrotransposons). The long terminal repeats, primer binding site, and polypurine tract sequences are highly similar among the LIRE elements, indicating that they are in the same lineage. Although the protein-coding regions were highly decayed, the sequence motifs of the integrase, reverse transcriptase, and RNase H domains were identifiable as belonging to the order of Ty1- copia elements. Phylogenetic analysis and primer binding site sequences revealed that these elements belonged to the Ale lineage among the six lineages of plant Ty1- copia elements. Base substitutions in the long terminal repeats estimated that the integration times of the LIRE Ty1- copia elements were between 0.7 and 5.5 mya. In situ hybridization showed that the LIRE elements were present in all the chromosomes of L. longiflorum and L. lancifolium, but absent in centromeres, telomeres, and 45S rRNA sites in both species. The LIRE elements were present very abundantly in species of the genus Lilium, but absent in other genera of the family Liliaceae, implying that the LIRE elements might have contributed to the expansion of the genome in the genus Lilium. [ABSTRACT FROM AUTHOR]

Abstract: The karyotypes of Fragaria species, diploid (Fragaria vesca ‘UC-01’, ‘Hawaii-30’, Fragaria nilgerrensis ‘Whiteberry’) and octoploid (Fragaria × ananassa ‘Akihime’), were analyzed using a method based on fluorescence in situ hybridization (FISH), using ribosomal DNA probes (5S rDNA and 45S rDNA). All diploid species of F. vesca and F. nilgerrensis had 2n =14 chromosomes, while F. × ananassa, an octoploid species, were 2n =56. The total length of somatic metaphase chromosome was measured as 12.22, 13.61, and 11.19μm for ‘UC-01’, ‘Hawaii-30’, and ‘Whiteberry’, respectively, and ‘Akihime’ measured 94.23μm. The karyotypes were composed of 6 pairs of metacentric and 1 pair of submetacentric in ‘UC-01’ and ‘Whiteberry’, and 5 pairs of metacentric and 2 pairs of submetacentric in ‘Hawaii-30’. 5S rDNA loci were detected in 1 pair from ‘UC-01’, ‘Hawaii-30’ and ‘Whiteberry’, and 45S rDNA loci were detected in 3 pairs from ‘UC-01’ and ‘Hawaii-30’, whereas 45S rDNA loci were detected in 2 pairs from ‘Whiteberry’. In octoploid strawberry ‘Akihime’, 45S rDNA signals were observed at 12 chromosomes, and 5S rDNA signals were observed at 2 chromosomes. [Copyright &y& Elsevier]