New Karyotype Information of Hymenocallis littoralis, Amaryllidaceae

Abstract

Hymenocallis littoralis was previously reported various chromosome numbers of 2n=44, 46, 48, 49 and 68 by a conventional staining. In order to analyze these chromosomes in detail, karyotype analysis by the conventional staining and a fluorescence in situ hybridization (FISH) using probes of 45S and 5S rDNA, and telomere repeats of human-type (TTAGGG)_n and Arabidopsis-type (TTTAGGG)_n was performed on chromosomes of H. littoralis from Thailand. The plants have 26 chromosome pairs (2n=52), and this chromosome number was not consistent with any of the previous reports. The 45S rDNA signals were localized at the terminal region of short arms of two chromosome pairs. Heteromorphic signals of 5S rDNA were detected at the proximal region of the short arms of one long chromosome, and at the interstitial region of the long arm of one short chromosome. The signals of human-type telomere repeat were detected at all chromosome ends, but FISH with Arabidopsis-type telomere repeat showed no signal.