Karyotype analysis of Lilium tigrinum by FISH

Abstract

The detailed karyotypes of diploid (2n = 2x = 24) and triploid (2n = 3x = 36) of L. tigrinum were constructed based on fluorescence in situ hybridization (FISH) using 5S rDNA and 45S rDNA probes. The lengths of mitotic metaphase chromosomes ranged from 15.92 to 30.18 um, with a total length/genome of 250.46 um in diploid, and 15.24 to 28.16 um, with a total length/genome of 233.42 um in triploid. The chromosome composed of two pairs of metacentrics (Chromosomes 1 and 2), four pairs of subtelocentrics (Chromosomes 3, 4, 5, and 6) and six pairs of telocentrics (Chromosomes 7, 8, 9, 10, 11, and 12) in diploid L. tigrinum, two pairs of metacentrics (Chromosomes 1 and 2), six pairs of subtelocentrics (Chromosomes 3, 4, 5, 6, 7, and 11) and four pairs of telocentrics (Chromosomes 8, 9, 10, and 12) in triploid L. tigrinum. Ten (Chromosomes 1, 2, 6, 7, and 11) or twelve (Chromosomes 1, 2, 4, 6, 7, and 11) loci of 45S rDNA were detected in the diploid chromosomes whereas fifteen loci were detected in triploid chromosomes (Chromosomes 1, 2, 6, 7, and 11). Two loci of 5S rDNAs were located close to each other at the both diploid and triploid chromosome 3. New cytotypes of secondary constriction were observed in diploid (1-1-1-0) and triploid (3-2-1-1).

Morphological characterization under different ecological habitats and physical mapping of 5S and 45S rDNA in Lilium distichum with fluorescence in situ hybridization

“…consist of tandem repeats, which proved to be efficient markers for in situ hybridization because they have the ability to conserve the DNA sequences present in high copy numbers, permitting the application of cloned heterologous probes (Lim et al 2005;Weiss-Schneeweiss et al 2007;Hwang et al 2015). Present FISH results showed considerable variations in the size, number, and position of 45S rDNA and 5S loci in L. distichum that cater effective molecular markers to identify karyotype structure variations associated with plant evolution and speciation (Hwang et al 2011).…”

Karyotype and Fluorescence In Situ Hybridization Analysis of 15 Lilium Species from China

“…And we did not observed 45S rDNA loci on chromosome 4 of L. lancifolium. Hwang et al (2011) also did not found 45S rDNA site on chromosome 4 in triploid L. lancifolium. But they found 45S rDNA signals on chromosome 4 in diploid L. lancifolium.…”

“…In our research, we did not find 45S rRNA signals on chromosomes 4 and 7, but we found signals located on chromosome 3, even though three of their materials were collected from the same region as ours. In a different study by Hwang et al (2011), 45S rDNA was located on chromosomes 1, 2, 6, 7, and 11. However, in that report, they analyzed the chromosomes mainly by short arm length and not by chromosome total length as in our study.…”

Patterns of chromosomal variation in Mexican species of Aeschynomene (Fabaceae, Papilionoideae) and their evolutionary and taxonomic implications

“…Its role in the organization of the nucleolus is obvious since secondary constrictions and satellites were often associated with projections of nucleolar material or even were observed immersed in a single nucleolus or in several small nucleoli, so here they are considered as nucleolar organizer regions (NORs). In this sense, secondary constrictions have been identified in different plant genera by in situ hybridization with rDNA probes and due to their correspondence with the SAT chromosomes it was possible to describe cytotypes in species and varieties with different levels of ploidy and even in hybrid taxa (Hasterok et al 2001, Taketa et al 2001, Kulak et al 2002, Marasek et al 2004, Hwang et al 2011, Roa and Guerra 2012. In addition, the use of conventional cytogenetic techniques has proven its usefulness in the identification of SAT chromosomes for taxa discrimination that exhibit a high degree of intraspecific karyotype uniformity (Solís Neffa and Fernández 2002).…”