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29-421: See List of Commelinaceae genera Commelinaceae is a family of flowering plants . In less formal contexts, the group is referred to as the dayflower family or spiderwort family . It is one of five families in the order Commelinales and by far the largest of these with about 731 known species in 41 genera. Well known genera include Commelina (dayflowers) and Tradescantia (spiderworts). The family

58-430: A few major staple crops such as potato and taro . Sugarcane stems are a major source of sugar. Maple sugar is obtained from trunks of maple trees. Vegetables from stems are asparagus , bamboo shoots , cactus pads or nopalitos , kohlrabi , and water chestnut . The spice, cinnamon is bark from a tree trunk. Gum arabic is an important food additive obtained from the trunks of Acacia senegal trees. Chicle ,

87-487: A myriad of arrangements and forms. They may be all fertile and equal or unequal, but in many genera two to four are staminodes (i.e. infertile, non-pollen producing stamens). Staminodes can alternate with the fertile stamens or they can all occur in the upper or lower hemisphere of the flower. The stalks of the stamens are bearded in many genera, although in some of these only some are bearded while others are hairless. Sometimes one to three stamens are absent altogether. Pollen

116-511: A reward to their pollinators. Most species are hermaphroditic , meaning each flower contains male and female organs, or andromonoecious, meaning that both bisexual and male flowers occur on the same plant. Floral dimorphism may be accompanied by variable pedicel length, filament length and/or curvature, or stamen number and/or position. Species tend to have specific flowering seasons, though local environmental factors tend to effect exact timing, sometimes considerably. Species tend to flower at

145-530: A specific time of day as well, with these periods being well defined enough to presumably isolate different species reproductively. Furthermore, some species exhibit differential opening times for male and bisexual flowers. Commelinaceae flowers tend to deceive pollinators by appearing to offer a larger reward than is actually present. This is accomplished with various adaptations such as yellow hairs or broad anther connectives that mimic pollen, or staminodes that lack pollen but appear like fertile stamens. Plants in

174-540: Is a list of Commelinaceae genera as of 2010. This list includes all genera recognised as current by the Kew World Checklist of Selected Plant Families. Note Node (botany) The stem is normally divided into nodes and internodes: The term " shoots " is often confused with "stems"; "shoots" generally refers to new fresh plant growth, including both stems and other structures like leaves or flowers. In most plants, stems are located above

203-406: Is classed as a thyrse , and each subunit is made up of cincinni ; this basically means that flowers are grouped in scorpion's tail-like clusters along a central axis, although this basic ground plan can become highly modified or reduced. Inflorescences or their subunit are sometimes enclosed in a leaf-like bract often called a spathe . Flowers can have either one or many planes of symmetry; that

232-595: Is diverse in both the Old World tropics and the New World tropics , with some genera present in both. The variation in morphology , especially that of the flower and inflorescence , is considered to be exceptionally high amongst the angiosperms . The family has always been recognized by most taxonomists. The APG III system of 2009 (unchanged from the APG system of 1998), also recognizes this family, and assigns it to

261-469: Is either zygomorphic or actinomorphic . They remain open for only a few hours after opening, after which they deliquesce . The flowers are usually all bisexual ( hermaphrodite ), but some species have both male and bisexual flowers ( andromonoecious ), the single species Callisia repens has bisexual and female flowers ( gynomonoecious ), and some have bisexual, male, and female flowers ( polygamomonoecious ). Nectaries are not found in any species within

290-423: Is present above the pericycle and vascular bundles. Woody dicots and many nonwoody dicots have secondary growth originating from their lateral or secondary meristems: the vascular cambium and the cork cambium or phellogen. The vascular cambium forms between the xylem and phloem in the vascular bundles and connects to form a continuous cylinder. The vascular cambium cells divide to produce secondary xylem to

319-399: Is the use of tree rings as a record of past climates. The aerial stem of an adult tree is called a trunk . The dead, usually darker inner wood of a large diameter trunk is termed the heartwood and is the result of tylosis . The outer, living wood is termed the sapwood. Vascular bundles are present throughout the monocot stem, although concentrated towards the outside. This differs from

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348-408: Is to distribute food from photosynthetic tissue to other tissues. The two tissues are separated by cambium , a tissue that divides to form xylem or phloem cells. Stems are often specialized for storage, asexual reproduction, protection, or photosynthesis , including the following: Stem usually consist of three tissues: dermal tissue , ground tissue , and vascular tissue . Dermal tissue covers

377-1087: Is usually released from slits that open on the sides of the anthers from top to bottom, but some species have pores that open at the tips. The Commelinaceae is a well supported monophyletic group according to the analysis of Burns et al. (2011). The following is a phylogeny , or evolutionary tree, of most of the genera in Commelinaceae based on DNA sequences from the plastid gene rbcL Cartonema Tinantia Weldenia Thyrsanthemum Elasis Tradescantia + Gibasis Callisia + Tripogandra Amischotolype Coleotrype Cyanotis Belosynapsis Dichorisandra Siderasis Cochliostema Plowmanianthus Geogenanthus Palisota Spatholirion Commelina Pollia Polyspatha Aneilema + Rhopalephora Floscopa Stanfieldiella Buforrestia Murdannia Anthericopsis All clades shown have 80% bootstrap support or better. List of Commelinaceae genera This

406-486: Is where the vascular tissue branches off to a frond . In cross section, the vascular tissue does not form a complete cylinder where a leaf gap occurs. Fern stems may have solenosteles or dictyosteles or variations of them. Many fern stems have phloem tissue on both sides of the xylem in cross-section. Foreign chemicals such as air pollutants, herbicides and pesticides can damage stem structures. There are thousands of species whose stems have economic uses. Stems provide

435-552: Is widely used to make paper , paperboard , cellulose sponges, cellophane and some important plastics and textiles , such as cellulose acetate and rayon . Bamboo stems also have hundreds of uses, including in paper, buildings, furniture, boats, musical instruments, fishing poles , water pipes , plant stakes, and scaffolding . Trunks of palms and tree ferns are often used for building. Stems of reed are an important building material for use in thatching in some areas. Tannins used for tanning leather are obtained from

464-540: The Commelinaceae are usually perennials , but a smaller number of species are annuals . They are always terrestrial except for plants in the genus Cochliostema , which are epiphytes . Plants typically have an erect or scrambling but ascending habit, often spreading by rooting at the nodes or by stolons . Some have rhizomes , and the genera Streptolirion , Aetheolirion , and some species of Spatholirion are climbers. The roots are either fibrous or form tubers . Leaves form sheaths at their bases that surround

493-606: The dicot stem that has a ring of vascular bundles and often none in the center. The shoot apex in monocot stems is more elongated. Leaf sheathes grow up around it, protecting it. This is true to some extent of almost all monocots. Monocots rarely produce secondary growth and are therefore seldom woody, with palms and bamboo being notable exceptions. However, many monocot stems increase in diameter via anomalous secondary growth. All gymnosperms are woody plants. Their stems are similar in structure to woody dicots except that most gymnosperms produce only tracheids in their xylem, not

522-415: The epidermis in function. Areas of loosely packed cells in the periderm that function in gas exchange are called lenticels. Secondary xylem is commercially important as wood. The seasonal variation in growth from the vascular cambium is what creates yearly tree rings in temperate climates. Tree rings are the basis of dendrochronology , which dates wooden objects and associated artifacts. Dendroclimatology

551-442: The family. There are always three sepals , although they may be equal or unequal, unfused or basally fused, petal-like or green. Likewise, there are always three petals, but these may be equal or in two forms, free or basally fused, white or coloured. The petals are sometimes clawed, meaning they narrow to stalk at the base where they attach to the rest of the flower. There are almost always six stamens in two whorls, but these occur in

580-511: The family: it is termed involute , and means that the margins at the leaf base are rolled in when they first emerge. However, some groups are supervolute or convolute . The inflorescences occur either as a terminal shoot at the top of the plant, or as terminal and axillary shoots arising from lower nodes , or rarely as only axillary shoots that pierce through the leaf sheath such as in Coleotrype and Amischotolype . The inflorescence

609-424: The inside and secondary phloem to the outside. As the stem increases in diameter due to production of secondary xylem and secondary phloem, the cortex and epidermis are eventually destroyed. Before the cortex is destroyed, a cork cambium develops there. The cork cambium divides to produce waterproof cork cells externally and sometimes phelloderm cells internally. Those three tissues form the periderm , which replaces

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638-716: The main ingredient in chewing gum , is obtained from trunks of the chicle tree. Medicines obtained from stems include quinine from the bark of cinchona trees, camphor distilled from wood of a tree in the same genus that provides cinnamon , and the muscle relaxant curare from the bark of tropical vines. Wood is used in thousands of ways; it can be used to create buildings , furniture , boats , airplanes , wagons , car parts, musical instruments , sports equipment , railroad ties , utility poles , fence posts, pilings , toothpicks , matches , plywood , coffins , shingles , barrel staves, toys , tool handles, picture frames , veneer , charcoal and firewood . Wood pulp

667-402: The order Commelinales in the clade commelinids in the monocots . The family counts several hundred species of herbaceous plants. Many are cultivated as ornamentals. The stems of these plants are generally well-developed, and often swollen at the nodes. Flowers are often short-lived, lasting for a day or less. The flowers of Commelinaceae are ephemeral, lack nectar , and offer only pollen as

696-777: The outer surface of the stem and usually functions to protect the stem tissue, and control gas exchange . The predominant cells of dermal tissue are epidermal cells . Ground tissue usually consists mainly of parenchyma , collenchyma and sclerenchyma cells ; and they surround vascular tissue. Ground tissue is important in aiding metabolic activities (eg. respiration , photosynthesis , transport, storage) as well as acting as structural support and forming new meristems . Most or all ground tissue may be lost in woody stems . Vascular tissue, consisting of xylem , phloem and cambium ; provides long distance transport of water , minerals and metabolites ( sugars , amino acids ); whilst aiding structural support and growth. The arrangement of

725-453: The soil surface, but some plants have underground stems . Stems have several main functions: Stems have two pipe-like tissues called xylem and phloem . The xylem tissue arises from the cell facing inside and transports water by the action of transpiration pull , capillary action , and root pressure . The phloem tissue arises from the cell facing outside and consists of sieve tubes and their companion cells. The function of phloem tissue

754-412: The stem, much like the leaves of grasses , except that the sheaths are closed and do not have a ligule . The leaves alternate up the stem and may be two-ranked or spirally arranged. The leaf blades are simple and entire (that is, they lack any teeth or lobes), they sometimes narrow at the base, and they are often succulent . The way in which the leaves typically unfurl from bud is a distinctive feature of

783-519: The vascular tissues varies widely among plant species . Dicot stems with primary growth have pith in the center, with vascular bundles forming a distinct ring visible when the stem is viewed in cross section. The outside of the stem is covered with an epidermis, which is covered by a waterproof cuticle. The epidermis also may contain stomata for gas exchange and multicellular stem hairs called trichomes . A cortex consisting of hypodermis (collenchyma cells) and endodermis (starch containing cells)

812-519: The vessels found in dicots. Gymnosperm wood also often contains resin ducts. Woody dicots are called hardwoods, e.g. oak , maple and walnut . In contrast, softwoods are gymnosperms, such as pine , spruce and fir . Most ferns have rhizomes with no vertical stem. The exception is tree ferns , which have vertical stems that can grow up to about 20 metres. The stem anatomy of ferns is more complicated than that of dicots because fern stems often have one or more leaf gaps in cross section. A leaf gap

841-408: The wood of certain trees, such as quebracho . Cork is obtained from the bark of the cork oak . Rubber is obtained from the trunks of Hevea brasiliensis . Rattan , used for furniture and baskets, is made from the stems of tropical vining palms. Bast fibers for textiles and rope are obtained from stems of plants like flax , hemp , jute and ramie . The earliest known paper was obtained from

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