Domestication of Australian trees for reforestation and agroforestry systems in developing countries

Global, India, Indonesia, Lao PDR, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam

Dr John Doran
Phone: 02 6281 8319
Fax: 02 6281 8312
Email: john.doran@csiro.au

• Global overseas collaborators, Global

$2,209,220

01/01/2000 - 30/06/2004

01/07/2004 - 31/12/2004

Dr John Fryer

In many countries people now face severe shortages of wood and wood products - through physical scarcity or because access to existing forest resources is restricted by commercial interests or government policies. Inadequate fuelwood compels poor people to collect fallen leaves and twigs for fuel from plantations, thereby disrupting nutrient cycling processes and impoverishing the soil.

Overall demand for fuelwood in the developing countries is expected to increase at an annual rate of 1.1 per cent; meanwhile, forest cover is steadily declining (in continental Southeast Asia at an average rate of 1.6 per cent per year). Land degradation and other changes brought about by reduced forest cover are causing substantial social, economic and environmental problems. Remaining natural forests and plantation forests are under greater harvesting pressure.

In many developing tropical and subtropical countries Australian trees have been planted (and are still being planted) to deal with the demand for forest products. The species are popular because many of them perform well on degraded, infertile sites, can deal with wide variations in climate and grow rapidly when the water supply is good. In developing countries around the world there are now more than 13 million ha of eucalypts, 2 million ha of acacias and 1 million ha of casuarinas in plantations, with many more Australian trees in agroforestry settings or scattered plantings.

But failure to use the best germplasm, and poor matching of species to the sites and to suitable uses for the product have over time reduced the benefits of using Australian trees. This domestication of Australian trees (DAT) project helped devise strategies to create more productive and sustainable planted forests in developing countries, using carefully selected Australian tree species. The work followed on from the earlier 'Seeds of Australian Trees' project funded by AusAID and ACIAR.

The major project objectives were to support more effective domestication and use of Australian tree species in low-income developing countries through provision of certified seed, training, and technical advice on the domestication and best use of Australian tree and shrub species.

The researchers undertook research to support the in-country mass production and effective use of genetically improved planting stock of Australian species. They sought more productive, sustainable and higher-value planted forests to provide environmental, social and economic benefits to these countries. The project comprised three subprojects. The first provided developing countries with certified seed of proven and promising Australian species, in line with their requests. The research team also carried out controlled hybridisations and created seed orchards and production areas in Australia and collaborating countries to produce seed of genetically improved species of established importance. The scientists also refined a recording system and database to help improve client access to germplasm information.
The second subproject provided information - publications, workshops and advisory visits in response to enquiries from clients. The TREDAT database provided information on species and provenance performance. And the third subproject was designed to increase clients' knowledge and skills in germplasm selection, tree improvement, silviculture, utilisation of wood products and management. The program included training in experimental design and analysis, and report writing.
Research work also included a component to investigate siting and management of seed orchards in developing countries, and to assess the productivity and value gains obtainable from such seed.

The main components of the project were seed supply, provision of technical advice and literature, and training. Research seedlots were sent to 44 recipients in 20 countries between January and December 2004. Developing-country researchers also received 87 copies of scientific and technical publications. Courses in Sri Lanka and Vietnam trained participants in seed orchard management and seed technology for seed orchards, including seed quality issues, seed collection, processing and documentation. A training course in Guangzhou, China, introduced software and methods for analysis of advanced-generation breeding populations.

Genetic gain trials established in the Philippines, India, Sri Lanka, Thailand and Vietnam enabled researchers to compare the performance of seed collected from in-country seed orchards established and managed by DAT collaborators with the original natural provenances used to establish the orchards as well as local commercial seed sources. These trials use large plot size (typically 36-tree or 49-tree square plots) and four or more replicates, in order to accurately rank the performance of the seedlots and determine whether trees grown from the seed orchard seedlots showed significant improvement in plantation performance. Two-year performance data from the genetic gain trials in the Philippines (Acacia mangium, Eucalyptus urophylla), Thailand (E. camaldulensis, two locations) and Vietnam (A. auriculiformis, A. mangium), and one-year performance data from Sri Lanka (E. grandis) were collated and analysed by partner organisations.

In summary, the studies found excellent performance of the orchard seedlots relative to natural provenance and commercial controls. The orchard seedlots were ranked best or close to best for height and diameter growth in all of these trials, and also displayed above-average survival. Treatment differences were statistically significant for most of the trials. For A. mangium in the Philippines the orchard seedlot had more than twice the 2-year conical stem volume of a locally used Mindanao land race of A. mangium, while in Vietnam the orchard A. auriculiformis had 38 per cent greater 2-year conical stem volume than the local commercial seed source, and significantly superior branching and stem straightness. In both these cases the orchard seedlots also significantly outperformed the natural-provenance controls, demonstrating that significant genetic improvement had been achieved in the orchards.

Partner research organisations in the collaborating countries are already using these results to promote the use of superior orchard seed over other local alternatives. Already in India small unreplicated demonstration trials of the orchard seedlots of E. camaldulensis and local alternative seed sources established on plantation company lands have led to strong commercial demand for seed from the DAT orchards.

Paclobutrazol treatment of eucalypt seed orchards in India, carried out during the project, led to substantial increases in flowering and seed production, and it is anticipated that this treatment will be used operationally to boost seed production of low-yielding species such as E. tereticornis. A new seed orchard of E. tereticornis was successfully established in Sri Lanka under the project, while in Vietnam clonal seed orchards of A. auriculiformis, A. mangium and E. camaldulensis were established in three locations across the country. The best 30 or so clones of each species, propagated from progeny trials, were established in a clone bank for intensive control-pollinated breeding, using clone bank technology transferred from CSIRO via the DAT project.

Project staff from CSIRO and from collaborating countries including China, Cambodia, India, Indonesia, Laos, Thailand, the Philippines and Vietnam attended a two-day meeting in Bangkok to review progress with domestication of key Australian species and plan for future collaboration after the conclusion of the project.