If many bracts are present and they are strictly connected to the stem, like in the family Asteraceae, the bracts might collectively be called an involucre. Leafy-bracted inflorescences: Intermediate between bracteate and leafy inflorescence.This use is not technically correct, as, despite their 'normal' appearance, these leaves are considered, in fact, bracts, so that 'leafy inflorescence' is preferable. Leafy inflorescences: Though often reduced in size, the bracts are unspecialised and look like the typical leaves of the plant, so that the term flowering stem is usually applied instead of inflorescence.Bracteate inflorescences: The bracts in the inflorescence are very specialised, sometimes reduced to small scales, divided or dissected.Ebracteate inflorescences: No bracts in the inflorescence.According to the presence or absence of bracts and their characteristics we can distinguish: They serve a variety of functions which include attracting pollinators and protecting young flowers. A bract is usually located at the node where the main stem of the inflorescence forms, joined to the rachis of the plant, but other bracts can exist within the inflorescence itself. Considering the broadest meaning of the term, any leaf associated with an inflorescence is called a bract. Inflorescences usually have modified foliage different from the vegetative part of the plant. These structural types are largely based on natural selection. These terms are general representations as plants in nature can have a combination of types. Inflorescences are described by many different characteristics including how the flowers are arranged on the peduncle, the blooming order of the flowers and how different clusters of flowers are grouped within it. 3.2 Meristems and inflorescence architecture.The rachis may be one of several types, including single, composite, umbel, spike or raceme. Inflorescences may be simple (single) or complex ( panicle). The fruiting stage of an inflorescence is known as an infructescence. Any flower in an inflorescence may be referred to as a floret, especially when the individual flowers are particularly small and borne in a tight cluster, such as in a pseudanthium. A flower that is not part of an inflorescence is called a solitary flower and its stalk is also referred to as a peduncle. The stalk of each flower in the inflorescence is called a pedicel. The major axis (incorrectly referred to as the main stem) above the peduncle bearing the flowers or secondary branches is called the rachis. The stem holding the whole inflorescence is called a peduncle. One can also define an inflorescence as the reproductive portion of a plant that bears a cluster of flowers in a specific pattern. The modifications can involve the length and the nature of the internodes and the phyllotaxis, as well as variations in the proportions, compressions, swellings, adnations, connations and reduction of main and secondary axes. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed. Aloe hereroensis, showing inflorescence with branched peduncleĪn inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches.
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