Nuclear chromatin organization, karyomorphological analysis and DNA amount in Vicia serratifolia Jacq.

The genus Vicia comprises about 160 species which are widely distributed and cultivated for food and fodder. In the recent classification of MAXTED et at. (1991) the genus Vicia is subdivided in two subgenera, namely Vicia and Vicilla with 17 and 9 sections respectively. Within Vicia subgenus, the section Faba is composed of three distinct units: two are monospecific (Vicia faba in the former and Vicia bithynica in the latter) while the third is larger and contains the seven species referred to Narbonensis complex. Vicia serratifolia Jacq. is one of seven species of the Narbonensis complex. The nuclear DNA content was determinated in meristematic root cells, karyotype and morphometric data were generated by an automated image analysis system and the distribution and staining properties of heterocromatin were assessed in metaphase chromosomes. Moreover Feulgen absorption at different thresholds of optical density provided evidence of th organization of the chromatin in interphase nucleus. The collected data were compared with those previously gathered in V. faba used as internal standard and V. narbonensis considered the reference species of the Narbonensis complex.