Selection of Italian cardoon genotypes as industrial crop for biomass and polyphenol production

Eight cardoon genotypes, of which seven Italian cultivated and one wild cardoon, belonging to the ENEA-Tuscia University joint collection, were assessed over two growing seasons with the aim of evaluating biomass production for pharmaceutical uses. Nine morphological descriptors (plant height and diameter, number of lateral shoots, main flower stem diameter, first fully developed leaf length and width, number of leaf lobes, plant fresh and dry weight) were selected to describe plant vigor and dry matter accumulation. Biochemical characterization of aboveground biomass was also undertaken, using accelerated solvent extraction (ASE) and HPLC analyses. Significant differences among genotypes were found for many of the agro-morphological traits evaluated. In particular, results identified aerial biomass yield, which ranged between 1095 and 2495 g plant(-1), as a useful trait in discriminating among genotypes. Significant differences among genotypes were also found for biomass polyphenol content. The most representative compounds detected were caffeoylquinic acids (3-O-caffeoylquinic acid and 1,5-O-dicaffeoylquinic acid) and flavonoid derivatives (cynaroside). The 3-O-caffeoylquinic acid content in biomass extracts ranged from 0.01 to 2.65 g kg(-1) DM, while the 1,5-O-dicaffeoylquinic acid varied from 3.08 to 4.07 g kg(-1) DM. With regard to cynaroside, the cultivated cardoon AFN showed the highest value (4.20 g kg(-1) DM). Taking into account that the analyzed germplasm has never been selected for biomass or polyphenol compound production, our data highlight the potential use of cardoon genotypes for biomass and pharmaceutical purposes. (C) 2013 Elsevier B.V. All rights reserved.