Vanda

Vanda tricolor

Vanda is a genus of the orchid family ( Orchidaceae). In her over 50 species are summarized. It is epiphytic growing plants, their distribution area is located in Southeast Asia. Some species, especially their hybrids are used as ornamental plants and in the cut flower production.

Description

Vanda has a monopodial growth form, the shoot is upright and can be very long, rarely the tip is tilted. The roots spring from the bottom of the stem axis, they are thick and sparrig spreading, surrounded by several layers of velamen radicum. The leaves are arranged in two rows. The internodes are short, the shoot axis is completely concealed by the leaf bases that comprise the shoot. Between the leaf base and the leaf blade is a separating tissue. The leaves are folded at the base V-shape along the midrib ( conduplikat ), earlier spread out flat. They are narrow, linear to strap- shaped, the tip is often slightly retracted and thus serrated asymmetrically bilobed or irregularly.

The inflorescence is a loose raceme, it appears from the leaf axils and comprises 3 to 15 flowers. They are usually large, colored, fragrant and wither - as long as they are not pollinated - only after a long time. The flowers are 'upside. The petals are not fused together and up on the lip about the same, usually spatulate, shaped each other. The lateral petals are often smaller than the outer petals in some species - such as the depicted Vanda tricolor - they are twisted at the base so that the back is facing forward. The edges of the petals are often wavy, their leaf surface can wear different colored veins or by puncturing a pattern. The lip is three-lobed and immobile grown on the column at the base it has a short, usually laterally compressed spur. The spur has, in contrast to related genera within no appendages or projections. The side lobes of the lip are small and beaten up. The middle lobe is significantly larger, often colored flashy, provided with longitudinal, but not very pronounced keels or ridges. The shape of the middle lobe is very different in different species, but usually it is convex. The column is short and fleshy, pedestal -like widened at the base. She wears the hood -shaped stamen. The two pollinia are round shaped, incised on a common stalks ( stipes ) with the large viscid disc ( Viscidium ) connected.

In some species, carpenter bees were ( Xylocopa ) observed as pollinators.

Dissemination

The species of the genus Vanda are common in Southeast Asia from India in the north- west to the Philippines, on the Indonesian islands and northeastern Australia. The greatest species diversity is found in the region of northern Thailand, Myanmar and southern Yünnans. They grow in moist or seasonally dry forests always, mostly in the lowlands to the low mountains.

Systematics and botanical history

The genus Vanda was erected in 1820 by Robert Brown. The name Vanda Jones already used in 1795 for the occurring in India Vanda tesselata; it is the common name in Hindi and is derived from Sanskrit.

Within the family of orchids Vanda belongs to the subtribe Aeridinae. A first genetic study with about 30 species mainly of the genera Vanda, Ascocentrum and Tower of the Winds has shown that Vanda, Ascocentrum, Euanthe Christians and Sonia are very closely related to each other. Vanda and Ascocentrum are therefore not monophyletic. However, new DNA analysis, the former genera Ascocentrum, Christians Sonia, Euanthe, Ascocentropsis, Neofinetia, Eparmatostigma and Trudelia have been integrated in the genus Vanda. Closely related to Vanda are also Luisia and Papilionanthe.

Within these genres, there are some well -supported ( bootstrap ) relationships. Vanda luzonica, Vanda tricolor and Euanthe sanderiana form a clade, probably including Vanda lamellata it. Vanda testacea is related to Vanda liouvillei; Vanda tessellata with Ascocentrum curvifolium; Christians Sonia vietnamica may garayi with Ascocentrum.

Use and Culture

Vanda species and hybrids are primarily used as ornamental plants and cut flowers. In the garden culture and the closely related Euanthe and Papilionanthe are managed as Vanda. As the first and influential breeding true Miss Joaquim, whose parent species are today counted to Papilionanthe. Important breeding partner was Vanda coerulea, the blue color is rare in orchids. An early and much-used hybrid is Vanda Vanda coerulea from Rothschildiana × Euanthe sanderiana. For cut flower production especially Arachnis hookerana was crossed.

The roots need air circulation and regular drying between Gießgängen. Most plants are grown coherently and bare root. Possible in the culture of corresponding cold- tolerant varieties is a free country residence in the summer with the highest possible light doses. After an appropriate adjustment period Vandeen tolerate the full midday sun, they require a large amount of light for flower induction. The nocturnal temperature drop and the continuous circulation of air outdoors affect the Blühfreudigkeit and the entire constitution of plants positive.