ALLOTETRAPLOID ORIGIN OF ALLIUM-ALTYNCOLICUM (ALLIACEAE, ALLIUM SECT SCHOENOPRASUM) AS INVESTIGATED BY KARYOLOGICAL AND MOLECULAR MARKERS

The tetraploid Allium altyncolicum (2n = 4x = 32) is considered to be of hybrid origin, because most of its morphological characters are int ermediate between those of its putative parents, A. schoenoprasum and A. ledebourianum. In the present work an attempt has been made to asce rtain its parentage by several methods: Giemsa C-banding, genomic in s itu hybridization (GISH), PCR-RFLP of cpDNA, restriction enzyme mappin g of the rDNA, and RAPDs. C-banding and GISH indicates clearly that A. altyncolicum is a segmental allopolyploid. Allium schoenoprasum and A . ledebourianum are the most likely the parental species and the large r part of the genome of A. altyncolicum (26 chromosomes) is derived fr om A. schoenoprasum. The low genetic divergence between these three sp ecies was confirmed by the lack of sequence variation in the ITS seque nces of nuclear rRNA genes and of the plastid rbcL-atpB intergenic spa cer. Both parental species and A. altyncolicum could be distinguished by RFLP of the rDNA repeats. The geographic origin of the putative par ental species was investigated using RAPDs.