Lorenzo Peruzzi

Karyotype asymmetry: again, how to measure and what to measure?

Abstract One of the most popular, cheap and widely used approaches in comparative cytogenetics – especially by botanists – is that concerning intrachromosomal and interchromosomal karyotype asymmetry. Currently, there is no clear indication of which method, among the many different ones reported in literature, is the most adequate to infer karyotype asymmetry (especially intrachromosomal), above all in view of the criticisms recently moved to the most recent proposal published. This work addresses a critical review of the methods so far proposed for estimation of karyotype asymmetry, using both artificial and real chromosome datasets. It is shown once again how the concept karyotype of asymmetry is composed by two kinds of estimation: interchromosomal and intrachromosomal asymmetries. For the first one, the use of Coefficient of Variation of Chromosome Length, a powerful statistical parameter, is here confirmed. For the second one, the most appropriate parameter is the new Mean Centromeric Asymmetry, where Centromeric Asymmetry for each chromosome in a complement is easily obtained by calculating the difference of relative lengths of long arm and short arm. The Coefficient of Variation of Centromeric Index, strongly criticized in recent literature, is an additional karyological parameter, not properly connected with karyotype asymmetry. This shows definitively what and how to measure to correctly infer karyotype asymmetry, by proposing to couple two already known parameters in a new way. Hopefully, it will be the basic future reference for all those scientists dealing with cytotaxonomy.

Contribution to the cytotaxonomical knowledge of Gagea Salisb. (Liliaceae) sect. Foliatae A. Terracc. and synthesis of karyological data

Abstract Four taxa belonging to the sectio Foliatae A. Terracc. (= Didymobolbos C. Koch) of the genus Gagea Salisb. are karyologically and morphologically investigated: G. chrysantha (Jan) J. A. Schultes and J. H. Schultes (= G. amblyopetala Boiss. and Heldr.; 2n =36), G. foliosa (J. and C. Presl) J.A. and J.H. Schultes (2n =36), G. bohemica (Zauschner) J.A. and J.H. Schultes var. saxatilis (Mert. and Koch.) Fiori (2n =48), G. granatellii (Parl.) Parl. (2n =36). All the studied populations come from Northern Calabria. Karyotype analysis is carried out for G. chrysantha and G. foliosa (both studied for the first time) and for G. bohemica. Karyological and morphological features of the four species are presented and discussed. An updated checklist of karyological data of the genus is presented and briefly discussed.

Karyological knowledge of the Italian vascular flora as inferred by the analysis of “Chrobase.it”

Abstract Chromosome number knowledge of the Italian vascular flora is stored in the online database Chrobase.it, which includes 6723 records, referable to 3428 taxa, 2799 accepted species and subspecies (about 35% of the national flora), and 3410 different chromosome countings (cytotypes). Appropriate queries to Chrobase.it allowed us to calculate mean, modal and median chromosome numbers for the Italian vascular flora, for geographical subgroups (islands, south, centre, north) and for selected orders, families and genera. Chromosome number data were available for 41 out of 55 orders (74%) and 107 out of 428 families (67%), represented by 664 out of 1297 genera (51%). The most studied administrative regions are Sicily (844 taxa), Tuscany (592 taxa), and Sardinia (390 taxa), while the most studied families are Asteraceae (465 taxa), Fabaceae (266 taxa), Brassicaceae (158 taxa), and Poaceae (144 taxa). Chromosome numbers range from 2n = 6, occurring in several species of Hypochaeris (Asteraceae), to 2n = 240, occurring in Ophioglossum (Ophioglossaceae), Dryopteris (Dryopteridaceae) and Arenaria (Caryophyllaceae) (mode is 2n = 18, and median is 2n = 24). Chromosome number variability was analyzed by frequencies (linear plots) and ANOVA, resulting in significant differences among geographical groups (mean chromosome number increasing from islands-south to centre-north) and selected taxa. B-chromosomes occur in 5.3% of data (148 taxa) and their number is not significantly different among geographical areas, while they occur only in 14 orders, 17 families, and 56 genera. The number of B-chromosomes ranges from 1 to 13 (mode = 1, median = 2).

Phytochemical and biological studies of Stachys species in relation to chemotaxonomy: A review

The genus Stachys is comprised of about 300 species spread throughout the world, hence representing one of the largest genera of the Lamiaceae. Several Stachys species have been exploited in traditional medicine as astringent, wound-healing, anti-diarrhoeal, anti-nephritic and anti-inflammatory agents. Moreover, antimicrobial, antioxidant and cytotoxic activities of some Stachys species are documented. Iridoids, flavonoids, phenolic acids and diterpenoids are reported as secondary metabolites of different species of this genus. The aim of the present review is to summarize and to highlight the recent advances in current knowledge on Stachys species and to compile reports of chemical constituents isolated from the genus Stachys over the past decades, together with their structural features, biological activities, and structure-activity relationships. Diversity of chemical constituents is discussed in relationship with current Stachys infrageneric taxonomy, classification and relationships with systematically close genera.

Is legal protection sufficient to ensure plant conservation? The Italian Red List of policy species as a case study

The conservation of species listed in the Bern Convention and European Directive 1992/43/EEC (so-called policy species) is mandatory for European Union (EU) countries. We assessed the conservation status of Italian policy species, based on the IUCN categories and criteria, to evaluate the effectiveness of existing protection measures at the national level. Among the 203 vascular plants, bryophytes and lichens evaluated, 41.9% are categorized as threatened, and one is already extinct, indicating that the protection measures for policy species are inadequate. Our results for the Italian policy species are consistent with those of an assessment at the EU level. Conservation priorities should be established at both the national and regional scales. An effective conservation strategy is needed, and in situ and ex situ actions focused on threatened species should be promoted.

Phylogenetic relationships of Gagea Salisb. (Liliaceae) in Italy, inferred from molecular and morphological data matrices

All known Italian Gagea species (23) representing seven out of 14 sections were included in this study. Morphological, molecular and combined data support the basal position of G. trinervia (Anthericoides). According to the molecular data, the sections Anthericoides, Lloydia, Gagea, Minimae and Spathaceae are very well supported; representatives of the sections Didymobulbos and Fistulosae clustered together in the same clade. In this clade, several near-related species groups (series) were recognised. According to 35 morpho-anatomical, ontogenetic and karyological data the section Gagea forms a well-defined monophyletic clade. Within this clade G. tisoniana, G. pusilla and G. cfr. paczoskii are near related. The position of the critical putative hybrid taxa G. luberonensis and G.polidorii is discussed. New series Solenarium (Dulac) Peruzzi and Tison, Occidentales (A. Terracc.) Peruzzi and Tison and Saxatiles (A. Terracc.) Peruzzi and Tison are proposed.

Are Red Lists really useful for plant conservation? The New Red List of the Italian Flora in the perspective of national conservation policies

“The New Red List of the Italian Flora” includes all the Italian policy species and other species of known conservation concerns for a total of 400 taxa, 65% of which are threatened with extinction. The Red List is based on a huge georeferenced data-set useful for conservation purposes.

Phylogenetic relationships of Italian Bellevalia species (Asparagaceae), inferred from morphology, karyology and molecular systematics

The seven Bellevalia species and subspecies known from Italy, representing about 10% of the genus and three out of six sections, were studied. An integrated morphological, karyological and molecular approach was used to infer phylogenetic and systematic relationships among them. B. romana (the generitype) is the most distinctive species on karyotype asymmetry grounds. B. boissieri and B.dubia, usually considered as subspecies of one species (the latter endemic to Sicily), deserve specific status based on biparental nrDNA markers (internal transcribed spacer, ITS), since they do not form a single clade. The allotetraploid endemic B. pelagica, morphologically similar to B. romana, is sister to the latter under parsimony, both in morphological and ITS trees; it is also related with B. dubia, based on karyotype asymmetry and a uniparental cpDNA marker (trnL(UAA)–trnF(GAA) IGS (intergenic spacer)). A second allotetraploid endemic, B. webbiana, is closely related, on morphological, karyological and molecular grounds, with B. boissieri and B. ciliata, and also with B. trifoliata, three species that might all involved in its origin. B. sect. Conicae Feinbr. and sect. Nutantes Feinbr. are here typified, the former (type: B. ciliata) is most likely a synonym of the latter (type: B. trifoliata).

Chromosome numbers of the Italian flora. From the Caryologia foundation to present

Abstract After slightly more than four decades from the first chromosome counts ever, the very first chromosome count on Italian plants was published in 1925 by Alberto Chiarugi. From this starting point, fundamental cornerstones of Italian plant karyology are: 1) the foundation, in Pisa, of the international journal Caryologia, now edited in Florence and indexed by ISI Web of Science© under the category Genetics and Heredity. 2) the constitution, within the Italian Botanical Society, of the Working Group for Plant Cytotaxonomy and Embryology (currently Plant Biosystematics), which in 1970 (still in Pisa) fostered the publication of the column Numeri Cromosomici per la Flora Italiana on the journal Informatore Botanico Italiano. 3) the constitution, at the end of the ‘90s, of the online database Chrobase.it – Chromosome numbers for the Italian flora. The history and role of cytotaxonomic research is highlighted, by reconstructing life and science of four eminent scientists: Alberto Chiarugi (1901-1960), Giuseppe Martinoli (1911-1970), Francesco D’Amato (1916-1998) and Emilio Battaglia (1917-2011). Despite 86 years of more or less continuous research, the geographical and taxonomical coverage of the Italian territory is still incomplete.

A proposal for a multivariate quantitative approach to infer karyological relationships among taxa.

Abstract Until now, basic karyological parameters have been used in different ways by researchers to infer karyological relationships among organisms. In the present study, we propose a standardized approach to this aim, integrating six different, not redundant, parameters in a multivariate PCoA analysis. These parameters are chromosome number, basic chromosome number, total haploid chromosome length, MCA (Mean Centromeric Asymmetry), CVCL (Coefficient of Variation of Chromosome Length) and CVCI (Coefficient of Variation of Centromeric Index). The method is exemplified with the application to several plant taxa, and its significance and limits are discussed in the light of current phylogenetic knowledge of these groups.