Cytological and Molecular Cytogenetic Insights into the Cynara cardunculus Genome

Abstract

Before the recent advances in molecular biology and sequencing techniques enabled a deep knowledge of the complete nucleotide sequence of many plant genomes, cytological and karyological studies have provided the first information concerning the genome organization of living beings. As stated by Figueroa and Bass (2010), plant cytogeneticists were among the earliest researchers who started to visualize genomes nearly a century before the first plant genome was sequenced (The Arabidopsis genome initiative 2000). In spite of the high development of next-generation sequencing approach and of the dramatic increase in available data regarding sequenced genomes, the cytological analysis of cell nucleus content remains a valuable tool for evolutionary studies and for structural and functional genomic research. Since Wilhelm Gottfried von Waldeyer-Hartz coined the term chromosome in 1888, many cytological techniques have been developed to disclose nucleus content and to allow a detailed description of the chromosome complement of plant species. Recently, some of these techniques have been applied to the cytological analysis and the molecular cytogenetic characterization of Cynara cardunculus complement, a traditional vegetable crop of the Mediterranean basin. The DNA content and a detailed karyotype of the two cultivated botanical varieties C. cardunculus var. altilis DC (cultivated cardoon) and C. cardunculus L. var. scolymus L. (globe artichoke) have been reported (Khaldi et al. 2014; Falistocco 2016; Giorgi et al. 2016). In this chapter, some of the used methodological approaches and the main results obtained by different authors will be discussed.