ABSTRACT
Plants that are generally herbaceous, annual, biennial, or perennial, rarely subshrubs, exceptionally trees (some species in tropical areas). They have a well-developed radicular system, which can include tuberized roots or adventitious buds. Underground stems may be present, and the aboveground stem can be simple, scapiform, or branched. The leaves are unstipulated, simple (entire or pinnately divided) or pinnately compound. Leaf arrangement is alternate or opposite, often in a basal rosette. The flowers are grouped in a specific racemose inflorescence (calathidium or anthodium). The receptacle of the inflorescence can be flat, convex, elongated, conical, globular, compact, or hollow, and it can be hairy or glabrous, depending on the species. Its size also varies. At the base of the inflorescence, there are involucral bracts that vary in size, shape, or consistency. The flowers are pentamerous, hermaphroditic or unisexual, actinomorphic or zygomorphic. Inflorescences typically have both types of flowers, both hermaphroditic and unisexual. The floral envelope consists of a reduced calyx (often formed by the persistent pappus on the fruit) and a gamopetalous corolla. The corolla can either be a tube terminated with 5 (rarely 8) teeth, characteristic of actinomorphic tubular flowers, or it can consist of a tube that continues with a long, linear extension on one side (ligule), terminated with 3–5 teeth, characteristic of zygomorphic ligulate flowers. The androecium consists of 5 stamens attached to the corolla tube by filaments, with long, introrse anthers, either fused or adherent, forming a tube through the middle of which the style passes (sinantherous androecium). The gynoecium consists of 2 united carpels, with a uniovulate ovary (anatropous ovule) positioned inferiorly, continuing into a long, cylindrical style with 2 stigmas at the tip, equipped with collecting hairs. At the base of the style, there are nectarines that secrete abundant nectar rich in sugar. The fruit is an achene (cypsela), which can have a persistent pappus, sometimes with setae or a coronule. Each fruit contains a single seed without endosperm. The number of species in this family is approximately 20,000, grouped into around 1,000 genera, making it the most well-represented family in Dicotyledonatae. The distribution of plants in this family covers a very large geographic and climatic range, from tropical to arctic regions, with the majority of species growing spontaneously in steppe areas. In Romania, there are 320 species belonging to 95 genera, ranging from the lowland to the mountainous regions. Due to the nectar produced by these plants, pollination is primarily entomophilous. Fruits are dispersed away from their place of origin either by wind or animals. In the case of anemochory, the presence of the pappus aids in dissemination, while in zoochory, the fruits often have retrorse spines. Among the many species within this family, only a relatively small number have practical significance, from an ornamental, industrial, culinary, or medicinal point of view.1– 4
