Gastrodia sesamoides

1.Introduction
2. Discription.
3.Habitat
4.Distribution
5.uses

Potato Orchid
Ku-ring-gai Chase National Park, Australia
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
Order:	Asparagales
Family:	Orchidaceae
Subfamily:	Epidendroideae
Genus:	Gastrodia
Species:	G. sesamoides
Binomial name
Gastrodia sesamoides R.Br.

Introduction

Gastrodia sesamoides is a saprophyte in the Orchid family. Common names include Potato Orchid, Native Potato, Bell Orchid and Cinnamon Bells.

The Potato Orchid is found in Australia and New Zealand. This leafless plant occurs in a variety of habitats; often growing in leaf litter in high rainfall areas. Indigenous Australians have been known to eat the tubers, hence the potato reference in the common name. Aboriginal peoples located the plants in habitat by observing where bandicoots had scratched in search of the tubers after detecting the plants underground by scent. The flavour of the tuber is said to resemble that of the beetroot, though insipid and watery. Within the tubers are beneficial bacteria and fungi. The fungal filaments supply soil nutrients to the plant and the root bacteria synthesizes nitrogen for the plant. The root tubers may grow to 15 cm (6 in) long and 4 cm (1.5 in) thick.

The original specimen was collected at Sydney in 1803. But now it is considered rare or extinct near Sydney. Flowering occurs between August and January, on a raceme. The flowers are self-pollinating and produce an appealing cinnamon-like scent. The flowers are somewhat unusual, as the sepals and petals are fused into a tube. Stems are between 30 and 60 cm (12 and 23.5 in) tall.

A difficult plant to grow in cultivation. The fungal and bacterial agents need to be present, and root disturbance is often fatal. Fungicides and fertilizers are to be avoided. A sheltered humus rich situation is preferred. Propagation from seed is not easy, and the collection of seeds in the wild is often illegal.

The specific epithet sesamoides refers to a supposed similarity to the sesame plant. This species first appeared in scientific literature in the year 1810, in the Prodromus Florae Novae Hollandiae, authored by the prolific Scottish botanist Robert Brown.

Description

Potato orchid in Southern Tasmania in Mixed rain forest (Photography by Jainee Bhalodi,University of Tasmania,School of plant Science)

G.sesamoides have robust spike with crowded tubular flower on a leafless stem which is up to 1m tall with 20 or more flower on it. This plants are saprophytic generally with brown color stem. It is also called ‘potato orchid’ due to its color and flower stems arise from large underground tuber which also give rise to the common name. They often occurs in loose colonies but rarely observed in groups depending on their growth. The flower have petal and sepals in small white or cream fan at the end of pale brown tube. Leaves are absent, stem are slender to modernly robust but sometimes up to 1 m in high, pale to brown arising from an underground rhizome. The flower are ranging from fewer to numerous, brown and white to 2 cm long and tubular in shape. Flowers have sweet spicy fragrance similar to cinnamon so it’s also called as cinnamon bells. The synonym used for this species is sesamoides. It can grows easily in soils with pH like acidic,alkaline ,basic and neutral soils.

Habitat

Gastrodia sesamoides is a saprophytic plant which is generally found in place like open situations, wet sclerophyll forests and dry sclerophyll forest, dry sclerophll woodlands, riparian areas and in leaf litter under snow gums and intermediate and high altitudes. Usually it’s observed in shady, well forested places in higher rainfall areas having more than 8oo mm rainfall per year, chiefly near decaying tree stumps, especially along creeks where large clumps of plants may appear in good seasons. Also recorded in areas where pine plantation are present, coastal sand-hill and heath. This plants are saprophytic. Its root are present all year and mainly occurs during summer season and flowering starts during early summer. G.sesmoides is world’s tallest orchid but smaller plant with slender stem and possess very few number of flower. The top part of the steam is very unique and distinctively bent when the plant is in budding stage.

Distribution

G.sesamoides is represented by about 35 species in which 7 are endemic in Australia other occurs in India, QLD, New Zealand, NSW, New Guinea, ACT, VIC, TAS and NZ. In South Australia, also occurs in MU, KI and SE regions. Considered uncommon in South Australia. The distinguishing character of this new entity is that it forms localized clonal groups with the flowering stems connected in a network of irregular subterranean rhizomes. This species can be also found in wet sclerophyll forest and mixed rain-forest.

Uses

'Potato orchid' attached to 1 m long tubular stem from its rhizoids growing in mixed rain-forest of Southern Tasmania.(Photography by Jainee Bhalodi,School of plant Science,University of Tasmania)

Underground rhizoids are rich in starch so it was used as food source by many indigenous Australian aboriginal people and it was important [art of their diet. Many people in other part of world like in Asian countries people use it in for making tea and herbal soup for getting health benefits. In India it is widely used in worshiping god and in decoration in marriage ceremonies. Its conservation status is very unique and highly restricted. It is also used in manufacturing perfumes for ladies, soaps for babies and many other application are there in regards to usage of its fragrances. Many herbal and Ayurveda medicines are prepared out of this species in India and also utilized in tea preparation. Many people in Australia and world around use this species as beautiful enhancing decorative plant in their houses and gardens. The root nodules in rhizoids of this plant help to fix nitrogen.Its root - raw or cooked. It resembles a beetroot in flavor but is watery and insipid.