Diascia is a genus of around 70 species[1] of herbaceous annual and perennial flowering plants of the family Scrophulariaceae,[2] native to southern Africa, including South Africa, Lesotho and neighbouring areas.
The perennial species are found mainly in summer-rainfall areas such as the KwaZulu-Natal Drakensberg; about 50 species, mostly annuals, are found in the Western Cape and Namaqualand, winter rainfall areas.
Their common name is twinspur, in reference to the two (usually downward-pointing) spurs to be found on the back of the flower.[3] These help to distinguish them from the similar (and closely related) genera Alonsoa and Nemesia. The spurs contain a special oil, which is collected in the wild by bees of the genus Rediviva (e.g. R. longimanus) that appear to have coevolved with the plants, as they have unusually long forelegs for collecting the oil.[4][5]
In gardens, Diascia cultivars (mostly hybrids) have become extremely popular as colourful, floriferous, easily grown bedding plants in recent years.[6]
Surprisingly, the generic name (from the Greek di = two and askos = bag, pouch or sack) does not refer to the spurs, but to the two translucent sacs, or pouches, known as 'windows', found in the upper part of the corolla of the original type specimen, Diascia bergiana. Diascia species in the section Racemosae have similar windows, but in some species they merge into one. The windows may help oil-collecting bees to find the correct position within the corolla when gathering oil from the glands within the spurs.[7]
Most diascia species are short-growing, straggling plants, reaching no more than 30–45 centimetres (12–18 in) in height, although Diascia rigescens can reach 60 cm (24 in), and the rather similar D. personata (with which it is often confused)[8] up to 120 cm (47 in) or so. Some Diascia species spread by means of stolons, while others produce multiple lax stems from a single crown. The flowers are borne in loose terminal racemes. The corolla is five-lobed, and normally pink or rose-coloured in the perennial species most commonly seen in cultivation. Dark purplish patches of oil glands may make the flowers of some species appear bicoloured.
Around 60–70 species are currently recognised in the genus Diascia:[9]
The two spurs found on the back of a Diascia flower (from which it gets the common name twinspur) contain a special oil, which is collected in the wild by at least 8 species of bees of the genus Rediviva. The bees appear to have coevolved with the plants, as the females have developed unusually long, hairy forelegs with which they collect the oil from Diascia spurs to feed their larvae (and sometimes to line their nests with).[10] The spurs vary in average length from 5.3 millimetres (0.21 in) to as much as 13.9 mm (0.55 in), mainly between species (although those of D. capsularis can vary widely between populations); the bees' forelegs vary similarly.[4] The spurs of Diascia longicornis are about 25 mm (0.98 in) in length, but the existence of a suitably equipped pollinator, Rediviva emdeorum, with forelegs of the same length, was only confirmed in the 1980s. Rediviva longimanus has also been observed pollinating D. longicornis in the Western Cape.[11]
Rediviva neliana, a widespread species, collects from at least 12 species of Diascia, but in general, few different Diascia species grow together in the same locality. As a result, local populations of R. neliana have been found to differ from each other, as each has developed legs that match the spur length of the diascias that are available to them in that locality. This indicates that local populations of R. neliana are coevolving with the flowers on which they depend.[4]
Diascia cultivars have become extremely popular worldwide as bedding plants, suitable for hanging baskets, window boxes and other containers, as well as rockeries and the fronts of herbaceous borders. This explosion of interest is largely thanks to the breeding work done by the late Hector Harrison of Appleby, North Lincolnshire, England. From 1985, he raised hundreds of hybrid seedlings, from which several excellent cultivars have been selected and named. He increased the colour range to include shades of apricot, pink, coral, lilac, red and white. Other nurseries and breeders have continued to build on his pioneering work.[6]
Several species and cultivars have been given the Award of Garden Merit by the British Royal Horticultural Society. The AGM includes a hardiness rating: most have been rated as intermediate between H3 (hardy outside in some regions or particular situations or which, while usually grown outside in summer, needs frost-free protection in winter – e.g. dahlias) and H4 (hardy throughout the British Isles).[12][13]
The species and cultivars commonly grown in gardens include the following (those awarded the Royal Horticultural Society's Award of Garden Merit are marked agm):[13][14]
Diascia is a genus of around 70 species of herbaceous annual and perennial flowering plants of the family Scrophulariaceae, native to southern Africa, including South Africa, Lesotho and neighbouring areas.
The perennial species are found mainly in summer-rainfall areas such as the KwaZulu-Natal Drakensberg; about 50 species, mostly annuals, are found in the Western Cape and Namaqualand, winter rainfall areas.
Their common name is twinspur, in reference to the two (usually downward-pointing) spurs to be found on the back of the flower. These help to distinguish them from the similar (and closely related) genera Alonsoa and Nemesia. The spurs contain a special oil, which is collected in the wild by bees of the genus Rediviva (e.g. R. longimanus) that appear to have coevolved with the plants, as they have unusually long forelegs for collecting the oil.
In gardens, Diascia cultivars (mostly hybrids) have become extremely popular as colourful, floriferous, easily grown bedding plants in recent years.
Diascia es un género con 65 especies de plantas de flores perteneciente a la familia Scrophulariaceae de Sudáfrica.
Datos: Q2568982
Multimedia:
Especies: Diascia (Scrophulariaceae)
Diascia es un género con 65 especies de plantas de flores perteneciente a la familia Scrophulariaceae de Sudáfrica.
Diascia Link & Otto, 1820 è un genere di piante della famiglia delle Scrophulariaceae. Comprende più di 25 specie originarie soprattutto del Sudafrica. Il genere non fa parte della flora italiana, ma viene utilizzato come specie ornamentale.
L'etimologia non è chiara. Potrebbe derivare dal greco dis (doppio) e askos(sacca), per la forma dei suoi fiori.
Si presentano come piante piuttosto basse, con foglie opposte e infiorescenze a racemi terminali. La fioritura va dalla primavera inoltrata all'autunno, con colori che vanno dal giallo all'arancione, dal violetto al bianco. Il calice è gamosepalo, formato da 5 sepali, e la corolla è gamopetala formata anch'essa da cinque petali.I due superiori, piccoli, sembrano saldati fra loro, i due laterali ottusi, arrotondati in cima, muniti di sperone lungo e arcuato alla base.Infine il petalo inferiore è grande e allungato.
Nel periodo invernale la pianta va in riposo vegetativo, con un progressivo disseccamento della parte aerea. Pur essendo per la maggior parte delle piante annuali in natura, in Europa si comportano da perenni.
Si suggerisce una posizione soleggiata, amano l'umidità ma non i ristagni d'acqua. Il terreno deve dunque essere fertile e ben drenato. Per favorire le fioriture si consiglia di cimare gli esemplari alla ripresa vegetativa, oltre che fornire un concime complesso ogni 10-15 giorni con le innaffiature. Non presenta particolari sensibilità a parassiti, tranne qualche sporadico attacco delle limacce, che possono danneggiare le foglie più tenere.
Diascia Link & Otto, 1820 è un genere di piante della famiglia delle Scrophulariaceae. Comprende più di 25 specie originarie soprattutto del Sudafrica. Il genere non fa parte della flora italiana, ma viene utilizzato come specie ornamentale.
Diascia (Diascia) – rodzaj roślin z rodziny trędownikowatych. Obejmuje ok. 50[3]–67[4] gatunków. Występują one w południowej Afryce, gdzie rosną w miejscach wilgotnych – nad strumieniami i na źródliskach oraz w miejscach piaszczystych mokrych w okresie zimowym[5]. Kilka gatunków (zwłaszcza diascia Barbery D. barbarae[6][3]) i mieszańców międzygatunkowych uprawianych jest jako rośliny ozdobne, przy czym walorem tych roślin jest ich długotrwałe kwitnienie[5].
Jeden z rodzajów z rodziny trędownikowatych Scrophulariaceae w jej wąskim ujęciu[1].
Diascia (Diascia) – rodzaj roślin z rodziny trędownikowatych. Obejmuje ok. 50–67 gatunków. Występują one w południowej Afryce, gdzie rosną w miejscach wilgotnych – nad strumieniami i na źródliskach oraz w miejscach piaszczystych mokrych w okresie zimowym. Kilka gatunków (zwłaszcza diascia Barbery D. barbarae) i mieszańców międzygatunkowych uprawianych jest jako rośliny ozdobne, przy czym walorem tych roślin jest ich długotrwałe kwitnienie.
Diascia é um género botânico pertencente à família Scrophulariaceae[1].
Diascia é um género botânico pertencente à família Scrophulariaceae.
«Diascia — World Flora Online». www.worldfloraonline.org. Consultado em 19 de agosto de 2020Diascia este un gen de plante din familia Scrophulariaceae.
Диасция (лат. Diascia) — род растений семейства Норичниковые (Scrophulariaceae), включает, по данным сайта The Plant List, 68[2] видов однолетних и полулистопадных, изредка вечнозеленых, иногда столонных многолетников в большинстве своем происходящих с гор Южной Африки.
Стебли прямостоячие, полегающие или стелющиеся. Листья супротивные сидячие яйцевидные, эллиптические, линейные зубчатые, обычно средне-зеленые. Цветки трубчатые, околоцветник 5-дольный, две верхние доли со шпорами и желтыми пятнами у основания, три нижние доли более крупные. Цветки собраны в верхушечную кисть. Цветение длится от начала июня до первых заморозков. Некоторые виды холодостойкие до −8°С. В условиях умеренного климата используют как однолетнее растение. Естественный ареал — Южная Африка.
Хорошо растет на солнечных местах, на влажных, питательных, с хорошим дренажем, почвах. В сухие периоды необходим регулярный полив. Отцветшие цветки надо отстранять, тогда цветение продлится.
Семена высевают в марте при 16 °С, посевной ящик накрывают стеклом, сеянцы высаживают в открытый грунт в мае; столонные виды делят весной; стеблевые зеленые черенки срезают весной с перезимивавших в теплице растений или укореняют полузрелые — срезанные летом. Молодые укорененные растения оставляют зимовать в теплице.
Слизни и улитки.
Применяют в передней части цветников, на солнечных берегах водоемов, на высокой клумбе, в рокарии, очень популярны как ампельное на балконах и террасах.
Диасция, цветки сорта Little Tango
Диасция, сорт 'Coral Belle'
Диасция 'Pink Butterfly'
Диасция
Диасция Personata Hopleys
Диасция (лат. Diascia) — род растений семейства Норичниковые (Scrophulariaceae), включает, по данным сайта The Plant List, 68 видов однолетних и полулистопадных, изредка вечнозеленых, иногда столонных многолетников в большинстве своем происходящих с гор Южной Африки.
.jpg)
