The University of Pretoria, in collaboration with several other international research organizations and the United StatesDepartment of Energy (DOE) Joint Genome Institute(JGI) , is working on enhancing the potential of eucalypt tree plantations to provide biofuels by studying the genes of these useful trees.

Eucalyptus tree species are native to Australia, but are grown in many tropical, subtropical and some temperate regions, often in marginal areas not suitable for agriculture. Eucalypt tree species and hybrids, in particular, are very fast-growing and have excellent wood properties. They are already used to produce a diverse array of products including pulp, paper, sawn timber, mine props, poles, firewood, charcoal, essential oils, honey and tannin, as well as for shade, shelter and soil reclamation.

In countries such as Brazil, eucalypts are already used intensively to produce energy from charcoal in a way that reduces the net production of greenhouse gases. Their ability to produce up to 100 m3 of cellulose-rich wood per hectare per year makes fast-growing eucalypt species premier candidates for the renewable production of bioethanol.

Now scientists are looking at the genes of eucalypts to understand why they are so superior in biomass production and carbon fixation.

In an energy economy based on sustained crude oil prices of more than US$60 per barrel, fast-growing, short-rotation, eucalypts would be excellent biomass crops for green energy production, particularly since these trees can grow on marginal lands and need not compete with food crops. They can also be harvested year-round, in contrast to seasonal crops.

“The availability of genomic research tools will allow scientists to determine the metabolic changes that are required to tailor fast-growing eucalypts for green energy production,” says Prof. Zander Myburg, from the University of Pretoria, who leads the Eucalyptus Tree Genome Project. Myburg is a researcher in theDepartment of Genetics at UP and directs the Forest Molecular Genetics Programme  in the Forestry and Agricultural Biotechnology Institute (FABI) . He also coordinates the International Eucalyptus Genome Network (EUCAGEN)  involving more than 130 scientists in 18 countries that have agreed to collaboratively develop public resources for Eucalyptus genomic research.

The international team will undertake the sequencing and characterization of the genome of a Eucalyptus tree in order to understand the basis of this tree’s superior properties and to extend these attributes to other species. “Genomics will allow us to adapt Eucalyptus trees for green energy production in regions such as the South-eastern USA where it cannot currently be grown,” explains Myburg. “Access to the Eucalyptus genome will also allow us to develop strategies to protect these trees from pathogens and pests that are currently threatening eucalypt plantations world-wide” says Prof. Mike Wingfield, Director of FABI and the Tree Protection Cooperative Programme (TPCP) [ http://www.fabinet.up.ac.za/tpcp/index] at UP.

In addition to leading the genome sequencing project, the University of Pretoria will lend its expertise to the project through, among other things, participating in an international project to construct a universal genotyping micro-array chip for commercially grown eucalypts and the joint curatorship of a genome browser after the completion of the sequencing and initial annotation by other stakeholders.

“Participation in the eucalypt genome project will greatly expand our ability to analyse complex plant genomes and offer exciting new opportunities for postgraduate student training” says Prof. Fourie Joubert, Director of the Bioinformatics and Computational Biology Unit  at UP.

“Eucalyptus species benefit from a large, diverse and collaborative scientific community worldwide and the University of Pretoria is very excited to be part of this important project,” says Myburg. “The project will also allow excellent opportunities for capacity development in developing countries such as South Africa and Brazil, which are both playing a leading role in the genome sequencing project”.

In South Africa the forest products industry contributes some R15-billion to the country's GDP annually and currently eucalyptus makes up approximately half of the 1.2 million ha planted to timber the country, clearly highlighting the importance of these species in the South African economy.

The announcement therefore represents a major milestone for all industries
that are focused on Eucalyptus - whether they are focused on small scale or
large scale bioenergy production or pulp and paper manufacture.

Zander Myburg with project co-leads Dario Grattapaglia from EMBRAPA and the Catholic University of Brasília in Brazil (left) and Jerry Tuskan of Oak Ridge National Laboratory in the United States (right).