November 21, 2012
UK Researchers Crack Dwarf Birch Genome For First Time
Brett Smith for redOrbit.com - Your Universe Online
Geneticists at Queen Mary University of London have successfully sequenced the genetic code of a birch tree, according to their report in the journal Molecular Ecology.
The sequencing of the dwarf birch could ultimately assist in its conservation throughout the United Kingdom, where its small population is considered vulnerable to a potential pest invasion.
"Dwarf birch is an excellent model for birch genomics, as its small size makes it easy to grow and experiment with, and it has a smaller genome than some other birch species,” said study co-author Richard Buggs, from Queen Mary's School of Biological and Chemical Sciences. “This genome sequence is a valuable resource for scientists studying birch trees around the world."
According to the report, birch trees are notoriously difficult to sequence because of their multiple sets of chromosomes — known as polyploidy — and hybridization.
Using cutting-edge sequencing technology, however, the researchers were able to identify and validate specific genetic markers. The identification of these markers allowed the team to finally crack the birch tree´s complex genetic code.
"This is a tremendous breakthrough,” said co-author Alan Featherstone, executive director of Trees for Life, a charity that conserves dwarf birch near Loch Ness, Scotland. “Together with our woodland restoration work at Dundreggan, where we have one of the greatest concentrations of dwarf birch in Scotland, it will do much to benefit the conservation of this important species."
The dwarf birch is quite common in northern Europe, particularly near the North Pole, where it is a crucial part of the Boreal forest, the largest land-based ecosystem in the world. The tree is less common in Scotland and the U.K. in general.
Many U.K. conservationists fear the influx of a stateside pest, the bronze birch borer, which American dwarf birches seem to be more resistant to than their British counterparts. The larvae of these beetles eat at the tree just under its bark, causing its branches to wilt and die.
Besides the adoption any infestation mitigation strategies, conservationists from Trees for Life and Highland Birchwoods are supporting PhD student, James Borrell, who is leading the effort to survey the genetic diversity among the dwarf birch populations in Scotland.
"This newly sequenced genome will be a hugely valuable tool in our effort to conserve this species,” said Borrell. “We are building on this to survey the genomic diversity of dwarf birch trees in Britain to inform management strategies."
Several management techniques are used to keep the beetles from decimating a birch population once they begin to occupy an area. First, the birch trees should be kept in good health and planted in cool, moist soil. Arborists also recommend that any infected trees should be cut down and destroyed before adult beetles emerge in the spring, especially those trees that shown signs of heavy infestation.
Experts say that insecticides can be applied to the tree bark to prevent any new attacks, but not for killing off any larvae. They recommend applying the insecticide three times during the spring and summer months.