Misplaced Pages

#35964

45-407: Six to 17 species, including: Paulownia catalpifolia Paulownia elongata Paulownia fargesii Paulownia fortunei Paulownia kawakamii Paulownia taiwaniana Paulownia tomentosa Paulownia ( / p ɔː ˈ l oʊ n i ə / paw- LOH -nee-ə ) is a genus of seven to 17 species of hardwood trees (depending on taxonomic authority) in the family Paulowniaceae ,

90-419: A peduncle . The main axis (also referred to as major stem) above the peduncle bearing the flowers or secondary branches is called the rachis . The stalk of each flower in the inflorescence is called a pedicel . A flower that is not part of an inflorescence is called a solitary flower and its stalk is also referred to as a peduncle. Any flower in an inflorescence may be referred to as a floret , especially when

135-532: A hypanthodium, which bears numerous flowers on the inside of a convex or involuted compound receptacle. The genus Euphorbia has cyathia (sing. cyathium ), usually organised in umbels. Some species have inflorescences reduced to composite flowers or pseudanthia , in which case it is difficult to differentiate between inflorescences and single flowers. Genes that shape inflorescence development have been studied at great length in Arabidopsis . LEAFY (LFY)

180-420: A panicle. The family Asteraceae is characterised by a highly specialised head technically called a calathid (but usually referred to as 'capitulum' or 'head'). The family Poaceae has a peculiar inflorescence of small spikes ( spikelets ) organised in panicles or spikes that are usually simply and improperly referred to as spike and panicle . The genus Ficus ( Moraceae ) has an inflorescence called

225-578: A single or a cluster of flower(s) is located at the axil of a bract, the location of the bract in relation to the stem holding the flower(s) is indicated by the use of different terms and may be a useful diagnostic indicator. Typical placement of bracts include: Metatopic placement of bracts include: There is no general consensus in defining the different inflorescences. The following is based on Focko Weberling 's Morphologie der Blüten und der Blütenstände (Stuttgart, 1981). The main groups of inflorescences are distinguished by branching. Within these groups,

270-402: A spicate (spike-like) inflorescence that is commonly called a spike . Simple inflorescences are the basis for compound inflorescences or synflorescences . The single flowers are there replaced by a simple inflorescence, which can be both a racemose or a cymose one. Compound inflorescences are composed of branched stems and can involve complicated arrangements that are difficult to trace back to

315-536: A terminal flower is formed and where flowering starts within the inflorescence. Indeterminate and determinate inflorescences are sometimes referred to as open and closed inflorescences respectively. The indeterminate patterning of flowers is derived from determinate flowers. It is suggested that indeterminate flowers have a common mechanism that prevents terminal flower growth. Based on phylogenetic analyses, this mechanism arose independently multiple times in different species. In an indeterminate inflorescence there

360-407: Is a definite inflorescence that is increasingly more strongly and irregularly branched from the top to the bottom and where each branching has a terminal flower. The so-called cymose corymb is similar to a racemose corymb but has a panicle-like structure. Another type of panicle is the anthela . An anthela is a cymose corymb with the lateral flowers higher than the central ones. A raceme in which

405-534: Is a gene that promotes floral meristem identity, regulating inflorescence development in Arabidopsis. Any alterations in timing of LFY expression can cause formation of different inflorescences in the plant. Genes similar in function to LFY include APETALA1 (AP1). Mutations in LFY, AP1, and similar promoting genes can cause conversion of flowers into shoots. In contrast to LEAFY, genes like terminal flower (TFL) support

450-681: Is a genus of angiosperm trees, and one of the fastest-growing trees in the world. Paulownia tomentosa can grow over 30 metres (98 ft) tall and has large heart shaped leaves ranging from 10–20 centimetres (4–8 in) wide and 15–30 centimetres (6–12 in) long with a 10–20 centimetres (4–8 in)-long petiole . The leaves grow in opposite decussate pairs, and as the name tomentosa suggests, are covered in hairs. The leaf margin can be toothed or entire and sometimes may be slightly lobed. They can be distinguished from common look-alike genera, such as Catalpa and Cercis , by secondary and tertiary venation . The leaves are late to come in on

495-411: Is also essential. Successful plantations usually purchase plants that have been professionally propagated from root cuttings or seedlings . Although seeds, seedlings, and roots of even mature trees are susceptible to rot, the wood is not and is used for boat building and surfboards. Dimensionally stable and given its straight grain and light weight, Paulownia timber is extremely easy to work with and

SECTION 10

#1732855865036

540-401: Is covered by a brown hairy indumentum , and the fused calyx tube is the same length as its calyx lobes, except in P. catalpifolia and P. elogata , in which the lobes are shorter than the calyx tubes. The corolla has five fused lobes with a shorter adaxial bilobed lip, and a somewhat longer abaxial trilobed lower lip. The lips of all the petals are curled and their surface tomentose. On

585-534: Is deep-rooting, and it is late-leafing, and its canopy is sparse enough to allow crops below it get enough light to grow while being sheltered from the wind . Paulownia is known in Japanese as kiri ( 桐 ) , specifically referring to P. tomentosa ; it is also known as the "princess tree". Paulownia is the mon of the office of prime minister , and also serves as the Government Seal of Japan used by

630-453: Is found in disturbed plots. Some US authorities consider the genus an invasive species , but in Europe, where it is also grown in gardens, it is not regarded as invasive. Paulownia trees produce as many as 20 million tiny seeds per year. However, the seeds are very susceptible to soil biota and only colonize well on sterile soils (such as after a high temperature wildfire ). Well-drained soil

675-434: Is no true terminal flower and the stem usually has a rudimentary end. In many cases the last true flower formed by the terminal bud ( subterminal flower) straightens up, appearing to be a terminal flower. Often a vestige of the terminal bud may be noticed higher on the stem. In determinate inflorescences the terminal flower is usually the first to mature (precursive development), while the others tend to mature starting from

720-499: Is normally called simply 'umbel'. Another kind of definite simple inflorescence is the raceme-like cyme or botryoid ; that is as a raceme with a terminal flower and is usually improperly called 'raceme'. A reduced raceme or cyme that grows in the axil of a bract is called a fascicle . A verticillaster is a fascicle with the structure of a dichasium; it is common among the Lamiaceae . Many verticillasters with reduced bracts can form

765-405: Is often called a panicle . This definition is very different from that given by Weberling . Compound umbels are umbels in which the single flowers are replaced by many smaller umbels called umbellets . The stem attaching the side umbellets to the main stem is called a ray . The most common kind of definite compound inflorescence is the panicle (of Webeling, or 'panicle-like cyme'). A panicle

810-522: Is popular for roadside planting and as an ornamental tree. Paulownia needs much light and does not like high water tables. As a forestry crop, Paulownia are exacting in their requirements, performing well only in very well draining soil, with summer rainfall or availability of irrigation water. Paulownia is extremely fast growing, increasing in height by up to 6 metres (20 ft) in one year when young. Some species of plantation Paulownia can be harvested for sawn timber in as little as five years. Once

855-450: Is reported to be resistant to decay, with good weathering characteristics. Trees can grow to maturity in under 10 years and produce strong, lightweight timber, good as firewood, and with an even higher strength to weight ratio than balsa wood. Its density is low at around 0.28 kilograms per liter (2.8 lb/imp gal), although significantly higher than balsa's very low 0.16 kilograms per liter (1.6 lb/imp gal). Paulownia

900-400: Is used as body material for low-cost electric guitars, as the core for lightweight touring skis, and for surfboard cores. It is typically used in guitars as the core body, then laminated under a more durable wood. Tested and confirmed species: Potential variety, hybrid, and synonym species: Paulownia catalpifolia Paulownia catalpifolia is a species of flowering plant in

945-476: Is used for chests , boxes, and clogs ( geta ). The wood is burned to make charcoal for sketching and powder for fireworks , the bark is made into a dye . The silvery-grey wood is sliced into veneers for special visiting cards. It is important in China, Korea, and Japan for making the soundboards of stringed musical instruments such as the guqin , guzheng , pipa , koto , and gayageum . More recently it

SECTION 20

#1732855865036

990-575: The Cabinet and the Government of Japan (whereas the chrysanthemum is the Imperial Seal of Japan ). It is one of the suits in the card game hanafuda , associated with the month of November or December (some regions reverse the order of these two months). Japan: An Illustrated Encyclopedia states: Paulownia wood is very light, fine-grained, and warp -resistant. It is the fastest-growing hardwood. It

1035-565: The activity of an inhibitor that prevents flowers from growing on the inflorescence apex (flower primordium initiation), maintaining inflorescence meristem identity. Both types of genes help shape flower development in accordance with the ABC model of flower development . Studies have been recently conducted or are ongoing for homologs of these genes in other flower species. Inflorescence-feeding insect herbivores shape inflorescences by reducing lifetime fitness (how much flowering occurs), seed production by

1080-468: The axis of a plant. 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. One can also define an inflorescence as the reproductive portion of a plant that bears a cluster of flowers in a specific pattern. Inflorescences are described by many different characteristics including how

1125-502: The basal sides of the ovary, beneath a hairy region. The ovary then develops into a sticky green oval capsule tapered at the apex with the remaining dried up style sometimes still attached. The capsule remains on the persistent brown calyx where it can last on the tree through the rest of the year before turning brown and woody, and loculicidal dehiscence reveals up to 2000 small winged seeds stacked tightly inside. The tiny seeds have lateral wings that gradually increase in length around

1170-421: The base of the stem. This pattern is called acropetal maturation. When flowers start to mature from the top of the stem, maturation is basipetal , whereas when the central mature first, maturation is divergent . As with leaves , flowers can be arranged on the stem according to many different patterns. See ' Phyllotaxis ' for in-depth descriptions. Similarly arrangement of leaf in bud is called Ptyxis. When

1215-590: The different axes. Some passage forms between the obvious ones are commonly admitted. Determinate simple inflorescences are generally called cymose . The main kind of cymose inflorescence is the cyme (pronounced / s aɪ m / ), from the Latin cyma in the sense 'cabbage sprout', from Greek kuma 'anything swollen'). Cymes are further divided according to this scheme: A cyme can also be so compressed that it looks like an umbel. Strictly speaking this kind of inflorescence could be called umbelliform cyme , although it

1260-400: The family Paulowniaceae , native to Shandong province, China, and introduced to Hungary. An extremely fast-growing tree, it is cultivated in China for its timber. This Lamiales article is a stub . You can help Misplaced Pages by expanding it . Inflorescence Morphologically , an inflorescence is the modified part of the shoot of seed plants where flowers are formed on

1305-408: The flowers are arranged on the peduncle, the blooming order of the flowers, and how different clusters of flowers are grouped within it. These terms are general representations as plants in nature can have a combination of types. Because flowers facilitate plant reproduction , inflorescence characteristics are largely a result of natural selection . The stem holding the whole inflorescence is called

1350-436: The individual flowers are particularly small and borne in a tight cluster, such as in a pseudanthium . The fruiting stage of an inflorescence is known as an infructescence . Inflorescences may be simple (single) or complex ( panicle ). The rachis may be one of several types, including single, composite, umbel, spike or raceme . In some species the flowers develop directly from the main stem or woody trunk, rather than from

1395-432: The inflorescences, and plant density, among other traits. In the absence of these herbivores, inflorescences usually produce more flower heads and seeds. Temperature can also variably shape inflorescence development. High temperatures can impair the proper development of flower buds or delay bud development in certain species, while in others an increase in temperature can hasten inflorescence development. The shift from

Paulownia - Misplaced Pages Continue

1440-419: The inner side of the lower trilobed corolla tube run two light-yellow folded ridges from the calyx to the lip. They are interpreted as floral guides to the top of the corolla tube. Inside the corolla tube, and approximately halfway down, are four stamen filaments fused to the petals at the base, with two being longer than the others. At the bottom of the corolla tube is a short corolla-stamen tube. The base of

1485-720: The late Zanclean stage of the Pliocene sites in Pocapaglia , Italy and Paulownia caucasica macrofossils have been recovered from strata of the Serravallian stage of the Miocene in Georgia in the Caucasus region. It is believed that the climate then would have been suitable for the genus across the whole northern hemisphere. In China, Paulownia ( Chinese : 泡桐 ; pinyin : pāotóng )

1530-469: The main branch. A kind of compound inflorescence is the double inflorescence , in which the basic structure is repeated in the place of single florets. For example, a double raceme is a raceme in which the single flowers are replaced by other simple racemes; the same structure can be repeated to form triple or more complex structures. Compound raceme inflorescences can either end with a final raceme ( homoeothetic ), or not ( heterothetic ). A compound raceme

1575-592: The most important characteristics are the intersection of the axes and different variations of the model. They may contain many flowers ( pluriflor ) or a few ( pauciflor ). Inflorescences can be simple or compound . Indeterminate simple inflorescences are generally called racemose / ˈ r æ s ɪ m oʊ s / . The main kind of racemose inflorescence is the raceme ( / ˈ r æ s iː m / , from classical Latin racemus , cluster of grapes ). The other kind of racemose inflorescences can all be derived from this one by dilation, compression, swelling or reduction of

1620-893: The order Lamiales . The genus and family are native to east Asia and are widespread across China. The genus, originally Pavlovnia but now usually spelled Paulownia , was named in honour of Anna Pavlovna, queen consort of The Netherlands (1795–1865), daughter of Tsar Paul I of Russia . It is also called "princess tree" for the same reason. It was originally sought after as an exotic ornamental tree in Europe and Asia, and later introduced to North America in 1844. Its fruits (botanically capsules ) were also used as packaging material for goods shipped from East Asia to North America, leading to Paulownia groves where they were dumped near major ports. The tree has not persisted prominently in US gardens, in part due to its overwintering brown fruits that some consider ugly. In some areas it has escaped cultivation and

1665-406: The plant's flowers are formed. On a larger scale, inflorescence architecture affects quality and quantity of offspring from selfing and outcrossing, as the architecture can influence pollination success. For example, Asclepias inflorescences have been shown to have an upper size limit, shaped by self-pollination levels due to crosses between inflorescences on the same plant or between flowers on

1710-541: The plant's main shoot. This is called cauliflory and is found across a number of plant families. An extreme version of this is flagelliflory where long, whip-like branches grow from the main trunk to the ground and even below it. Inflorescences form directly on these branches. Plant organs can grow according to two different schemes, namely monopodial or racemose and sympodial or cymose . In inflorescences these two different growth patterns are called indeterminate and determinate respectively, and indicate whether

1755-691: The seed. The ventral and dorsal side of the seed are flat. The wing shape on the seeds is another characteristic distinguishing Paulownia from the rest of the Lamiales. The new buds, enclosed by the early brown fuzzy calyx, are visible in late summer to early fall and wait dormant, alongside the brown seed capsules, till spring. Paulownia once occurred in North America , with fossilized leaves being found in Tertiary strata of Ellensburg Canyon of Washington state . Paulownia macrofossils have been recovered from

1800-403: The single flowers are replaced by cymes is called a (indefinite) thyrse . The secondary cymes can be of any of the different types of dichasia and monochasia. A botryoid in which the single flowers are replaced by cymes is a definite thyrse or thyrsoid . Thyrses are often confusingly called panicles . Other combinations are possible. For example, heads or umbels may be arranged in a corymb or

1845-404: The stamen filaments are bent so that they run along the upper portion of the flower with the arrow shaped anthers then depositing pollen on the dorsal side of a variety of pollen-feeding insects. The superior bilocular ovary , surrounded by the brown calyx, with its stigma and style rising up, is approximately the same length as the longer stamen filaments that surround it. That is left on

Paulownia - Misplaced Pages Continue

1890-413: The stem as the corolla and stamen fall off. The stigma tip has a singular small hole that leads to a tubular dilated chamber at the top of the style, covered in receptive papillae. In the species P. kawakamii , the stigma tip is slightly bilobed, which is a unique morphological characteristic distinguishing Paulownia from all of the Lamiales. At the bottom of the ovary is a nectary , with nectary slits on

1935-453: The tree and late to fall from the typically deciduous Paulownia . However, in tropical areas, the tree can be evergreen. The leaves are often preceded by pale violet to purple-shaded tubular flowers, similar to a foxglove . Like most members of the Lamiales, the flowers are zygomorphic . The inflorescences are terminal erect 15–30 centimetres (6–12 in)-long panicles of ~5 centimetres (2 in) long flowers. The thick, fused calyx

1980-494: The trees are harvested, they regenerate from their existing root systems, earning them the name of the "Phoenix tree" (that name is alternatively attributed to the belief that it is the only tree within which the phoenix will roost.) Paulownia is also used in Chinese agroforestry systems because it grows quickly, its wood is light but strong, its flowers are rich in nectar , its leaves make good fodder for farm animals , it

2025-406: The vegetative to reproductive phase of a flower involves the development of an inflorescence meristem that generates floral meristems. Plant inflorescence architecture depends on which meristems becomes flowers and which become shoots. Consequently, genes that regulate floral meristem identity play major roles in determining inflorescence architecture because their expression domain will direct where

#35964