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Many weeds produce dormant seeds that are unable to complete germination under favourable conditions. There are two types of seed dormancy: primary dormancy (innate dormancy), in which seeds are in a dormant state upon release from the parent plant, and secondary dormancy (induced dormancy), in which dormancy develops in seeds through some experience after release from the parent plant. Mechanisms of seed dormancy are categorized as embryo dormancy and coat-imposed dormancy. In embryo dormancy, the control of dormancy resides within the embryo itself, and in coat-imposed dormancy, it is maintained by the structures enclosing the embryo. Many factors can influence seed dormancy during development and after dispersal; they can be abiotic, biotic, or a combination of both. Most weeds deposit a large number of seeds in the seed bank, which can be one of two types—transient or persistent. In the transient type, all viable seeds in the soil germinate or die within one year, and there is no carry-over until a new crop is deposited. In the persistent type, at least some seeds survive in the soil for more than one year and there is always some carry-over until a new crop is deposited. Some dormant seeds require after-ripening—changes in dry seeds that cause or improve germination. Nondormant, viable seeds can germinate if they encounter appropriate conditions. In the face of climate change, including global warming, some weeds produce a large proportion of nondormant seeds, which germinate shortly after dispersal, and a smaller, more transient seed bank. Further studies are required to explore this phenomenon. Full article

For many years, plants have been used in the traditional medicine of different cultures. The biennial plant of the family Asteraceae, Onopordum acanthium L., also known as Scotch thistle, is used in traditional medicine as an anti-inflammatory, antitumor, and cardiotonic agent. The plant is widespread in the world; it grows in Europe and Asia and was introduced to America and Australia. Stems and buds of the first-year plant are used in cooking as an analogue of artichoke in European cuisine. Additionally, inflorescences contain a complex of proteolytic enzymes “onopordosin”, which may be used as a milk-clotting agent in the dairy industry. The chemical composition of the aerial part and roots of O. acanthium is represented by flavonoids, phenylpropanoids, lignans, triterpenoids, sesquiterpene lactones, and sterols. The anti-inflammatory, antiproliferative, and cardiotonic properties of the plant have been confirmed by pharmacological experiments with extracts and individual compounds using in silico, in vitro, and in vivo methods. This work is a review of information on the chemical composition and pharmacological studies of O. acanthium as a promising medicinal plant. Full article