No abstract

Milk thistle [Silybum marianum (L.) Gaertn.] is an officinal crop species native to the Mediterranean. The species is gaining increasing interest as a multipurpose crop, but lack of information exists about the natural phenotypic variability available in the species for the traits of interest. In the present work, the fruit morphological and chemical traits of a collection of 26 milk thistle accessions have been analyzed. The results show that the most variable traits are related to single flavonolignan content. When the most abundant fatty acids present in the fruit are considered, oleic acid appears to have the higher variability between accessions. Correlations between variables highlight strong relationships between the different flavonolignans and a strong positive correlation between isosilybin A and the total silymarin content, suggesting a central role of this minor flavonolignan in silymarin biosynthetic pathway. The clustering procedure displays considerable diversity between the accessions that originate from localities where milk thistle is described as a native species.

Silybum marianum (milk thistle) is currently utilised as a medicinal plant which provides raw material for the production of silymarin. Silymarin is composed of a group of flavonolignans that are well known and studied for their medicinal properties. However, the biomass yield potential and the chemical composition of its biomass suggest opportunities for much broader utilisation of S. marianum. This paper reviews the available literature about S. marianum biomass productivity and composition and about properties of products and byproducts of silymarin extraction. Alternative uses of whole plant biomass include fodder, bioenergy production and phytoremediation. Byproducts of silymarin extraction such as oil and flour have possible applications in food, feed and cosmetics. Moreover, the review explores potential alternative applications of silymarin. We conclude that a pivotal issue for further utilisation of S. marianum is the development of improved cultivars suited for the different possible utilisations.

Silybum marianum is a medicinal plant cultivated for silymarin production in central Europe and Asia. It is also considered a weed of both arable lands and pastures. Although S. marianum still exhibits traits that are typical of wild species; both its fruit and biomass productivity are remarkable. Therefore, the species is gaining interest as a potential novel commercial crop for multiple uses (i.e. medicinal plant, bioenergy, and vegetable oil production). Despite the intriguing characteristics of this plant and its economic importance, a detailed description of the phenological growth stages of S. marianum has never been developed. A precise and univocal description of the growth stages of this species will offer a useful tool for several agronomic and research activities, weed management practices and for further genetic improvement programmes. In the present manuscript, the description of the phenological development of S. marianum is proposed utilising the extended BBCH (Biologische Bundesantalt, Bundessortenamt and Chemische Industrie) scale. The phenological growth stages are described utilising both the 2‐ and 3‐digit BBCH coding system. Pictures of the most representative stages supplement the manuscript.