King's Lomatia
Encyclopedia
King's Lomatia is a Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...

n shrub from the family Proteaceae
Proteaceae
Proteaceae is a family of flowering plants distributed in the Southern Hemisphere. The family comprises about 80 genera with about 1600 species. Together with the Platanaceae and Nelumbonaceae they make up the order Proteales. Well known genera include Protea, Banksia, Embothrium, Grevillea,...

. The plant has shiny green leaves and bears pink flowers, but yields neither fruit nor seeds. Only one colony of King's Lomatia is known to be alive in the wild. It is also sometimes called "King's Holly", though it is not a holly
Holly
Ilex) is a genus of 400 to 600 species of flowering plants in the family Aquifoliaceae, and the only living genus in that family. The species are evergreen and deciduous trees, shrubs, and climbers from tropics to temperate zones world wide....

.

King's Lomatia is unusual because all of the remaining plants are genetically
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....

 identical. Because it has three sets of chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...

s (a triploid) and is therefore sterile
Infertility
Infertility primarily refers to the biological inability of a person to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term...

, reproduction occurs only vegetatively: when a branch falls, that branch grows new roots, establishing a new plant that is genetically identical to its parent.

Although all the plants are technically separate in that each has its own root system, they are collectively considered to be one of the oldest living plant clones
Cloning
Cloning in biology is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. Cloning in biotechnology refers to processes used to create copies of DNA fragments , cells , or...

. Each plant's life span is approximately 300 years, but the plant has been cloning itself for at least 43,600 years (possibly up to 135,000 years). This estimate is based on the radiocarbon dating
Radiocarbon dating
Radiocarbon dating is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" ,...

 of fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

ised leaf fragments that were found 8.5 km away. The fossilised fragments are identical to the contemporary plant in cell structure and shape, which indicates that both plants are triploid
Polyploidy
Polyploid is a term used to describe cells and organisms containing more than two paired sets of chromosomes. Most eukaryotic species are diploid, meaning they have two sets of chromosomes — one set inherited from each parent. However polyploidy is found in some organisms and is especially common...

 and therefore clones due to the extreme rarity of the occurrence of triploidy.

History

In 1937 Charles Denison "Deny" King
Deny King
Charles Denison Deny King AM was an Australian naturalist, ornithologist, environmentalist, painter and miner. He spent fifty five years living in Melaleuca in the remote South West Wilderness of Tasmania where he discovered the extinct shrub, Banksia kingii.King was a tin miner by profession and...

 discovered the plant while mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

 tin
Tin
Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...

 in the remote southwest of Tasmania. The Tasmanian Herbarium named the plant in King's honour after he sent specimens to be identified in the 1960s. The plant group that King discovered in 1937 has disappeared (and likely died out), and the sole remaining group of approximately 500 plants covers a 1.2 kilometer-long area in the extreme southwest of Tasmania. This area is prone to fires and other natural threats to the plants, so Tasmania has begun an effort to develop other populations in controlled environments such as the Royal Tasmanian Botanical Gardens
Royal Tasmanian Botanical Gardens
The Royal Tasmanian Botanical Gardens, which cover an area of approximately 14 hectares , were established in Hobart in 1818 and are located within the Queens Domain. The Gardens hold historic plant collections and a large number of significant trees, many dating back to the nineteenth century...

. (Because of its fragility and rarity, their specimens are not on display to the public.) Due to its inability to reproduce sexually, there is no possibility of increasing the plant's genetic diversity to promote disease resistance.

However, on 19 September 2009, the Royal Tasmanian Botanical Gardens issued a media release regarding the propagation efforts saying: "The Royal Tasmanian Botanical Gardens [RTBG] is working towards securing the future of a rare and ancient Tasmanian native plant... Lomatia tasmanica, commonly known as King's Lomatia, is critically endangered with less than 500 plants growing in the wild in a tiny pocket of Tasmania's isolated south west. The RTBG has been propagating the plant from cuttings since 1994... 'Fossil leaves of the plant found in the south west were dated at 43,600 years old and given that the species is a clone, it is possibly the oldest living plant in the world"
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK