Morpho-anatomical differentiation and genome size variation in three ploidy levels within the B7 cytotype of Prospero autumnale (Hyacinthaceae) complex from the Balkan Peninsula and Pannonian Basin

Abstract

Prospero autumnale (Hyacinthaceae) is taxonomically intricate geophyte species complex with a circum-Mediterranean distribution. In contrast to the extraordinary karyological diversity within P. autumnale complex, morphological variation is limited, and thus, reliable taxonomically diagnostic traits are absent. This investigation addresses whether different ploidy levels within cytotype B7 can be distinguished morpho-anatomically. Populations of B7 cytotype from the Balkan Peninsula and Pannonian Basin were examined. Karyological variation was analyzed, and genome size measurements via flow cytometry were taken for selected individuals from each population. Morpho-anatomical analyses were based on 29 anatomical and 25 morphological traits. Multivariate morphometric analyses revealed significant differences between the three ploidy levels, and this may assist in the identification of plant ploidy level. Although the diploids were the most distinct group, some differences were also found between tetraploids and hexaploids. Genome size variation was found within diploids and tetraploids, and some downsizing was observed in hexaploids. This is the first evaluation of morpho-anatomical variation of cytotype B7 in the P. autumnale complex using a multivariate morphometric approach; further taxonomic and evolutionary studies in this taxonomically complex group are needed.