Micropropagation

Conservation programmes

Bryophytes

Also known as mosses and liverworts, these are plant pioneers and fill a vital niche in the ecology of many habitats.

The UK has an exceptional diversity of bryophytes with approximately 600 moss and 300 liverwort species. Of these, 50 are listed for attention under the UK Biodiversity Action Plan (UKBAP). In collaboration with the UK statutory conservation agencies, Kew is developing ways of propagating and storing these species using in vitro and cryogenic techniques. In this unique project, novel methods of culture have been developed using the endangered endemic UK moss, Ditrichum cornubicum.

Several priority species are now in culture and cryo-storage. Samples of the critically endangered Orthodontium gracile have been collected from 16 sites and are being material multiplied in tissue culture. This will provide a source of uncontaminated DNA for genetic fingerprinting as well as material for possible re-establishment trials.

Ferns

Fern species that are rare or difficult to propagate from spores may be propagated in vitro. The techniques used reduce the risk of spores of different species becoming mixed. Successes with plants of conservation concern include the Tunbridge filmy fern, Hymenophyllum tunbrigense. This species produces green spores that can only be stored for a few days; micropropagation allows rapid germination and growth. These techniques are assisting the regional recovery programme for this species in the Sussex Weald.

Orchids

 
  Laboratory grown seedlings of Anacamptis laxiflora planted at Wakehurst Place
 

In nature most orchids form a symbiotic (mutually beneficial) association with fungi in order to help the plant obtain nutrients. This association is essential for the germination of orchid seeds that lack their own internal food supplies (endosperm).

The Sainsbury Orchid Conservation Project was established to investigate techniques for germination of temperate terrestrial orchids in the laboratory using fungi.

Many tropical epiphytic and terrestrial orchids are grown from seed in vitro at Kew. The media on which the seeds grow contains nutrients to sustain the seedling and so a mycorrhizal fungus is not needed, it is therefore called asymbiotic. With good quality fresh seed, very high levels of germination can be achieved in vitro, this allows thousands of seedlings to be produced from a single capsule.

Working in collaboration with the Tsimbazaz Botanical and Zoological Park, seed was collected from endangered species such as Bulbophyllum elliotii and plants returned to Madagascar to help support dwindling populations. The laboratory continues this support through the Threatened Plants of Madagascar Appeal.

Kew is a lead partner in several of the UK Species Action Plans for endangered orchids such as that for the Fen orchid (Liparis loeselii) and the Lady’s slipper orchid (Cypripedium calceolus) which is one of the UK’s rarest orchids. In collaboration with English Nature, seedlings of the Lady’s slipper orchid have now been reintroduced and the first flowering was reported in 2000.

Occasionally surplus in vitro orchid protocorms are available to other Botanic Gardens and research organisations if they have laboratory facilities available to grow them on, and provided they agree to abide by, and sign, RBG Kew's material transfer agreement, which prohibits commercial use or passing of the material to third parties without gaining prior permission from RBG Kew.

For countries outside the EU, RBG Kew can provide phytosanitary certificates. It is the recipients' responsibility to provide any necessary plant import permits with their request. In vitro protocorms are exempt from the current CITES regulations.

For enquiries as to available stock and requests please contact: microprop@kew.org

Micropropagation
Micropropagation: Support for living collection