Sandalwood Biblio - Cropwatch

especially Acacia acuminata. This establishment technique has been very effective, with over 80
% survival per spot, and mean stem diameters (at 150 mm above the ground) increasing at 10-12
mm yr-1near A. acuminata. Allowing two years to establish both A. acuminata and S. spicatum,
and then a mean stem diameter growth of only 7 mm yr-1for 18 years, the S. spicatum are
expected to reach commercial size (127 mm) at plantation age 20 years. At this age, the
expected yields are approximately 4.4 tonnes ha-1, with a net return ofover AU $14,000 ha-1.
The sandalwood trees are also producing 60-170 kg ha- 1of seeds at age only 4-6 years. The
value of the seeds may also provide a supple-mentary income to the sandalwood growers, while
they are waiting for the trees to reach commercial size. Cropwatch comments: The authors
state that core samples taken from 10-year old trees produced oil containing 16.7 to 21.1% α- &
β-santalols, “which are the compounds that produce the distinct sandalwood fragrance”
referencing Adams et al. (1975), The authors take no account of the effect on the odour profile of
other major components found in the oil, such as the presence of 17.8% to 20.5% farnesol, a
sesquiterpene alcohol recently identified as a sensitiser by IFRA and the subject of a recent
SCCP Opinion.
Braun N.A. & Meier M. (2004) “Western Australian & East Indian sandalwood oil – a comparison”
Euro Cosmetics 12(1), 22-29.
Bristow, M. et al. 2000. "Queensland sandalwood (Santalum lanceolatum): regeneration following
harvesting." Sandalwood Research Newsletter 11, 4-8.
Burfield T. & Wildwood C. (2004) “Cropwatch 2: Australian Sandalwood Oil: a tale of Spin &
Hype” at http://www.cropwatch.org/cropwatch2.htm & www.users.globalnet.co.uk/~nodice/
Byrne M., McDonald B. & Brand J. (2003) “Phylogeography & divergence in the chloroplast
genome of Western Australian sandalwood (Santalum spicatum) Heredity 91(4), 389-395.
Abstract. Western Australian sandalwood (Santalum spicatum) is widespread throughout Western
Australia across the semiarid and arid regions. The diversity and phylogeographic patterns within
the chloroplast genome of S. spicatum were investigated using restriction fragment length
polymorphism analysis of 23 populations. The chloroplast diversity was structured into two main
clades that were geographically separated, one centred in the southern (semiarid region) and the
other in the northern (arid) region. Fragmentation due to climatic instability was identified as the
most likely influence on the differentiation of the lineages. The lineage in the arid region showed a
greater level of differentiation than that in the southern region, suggesting a higher level of gene
flow or a more recent range expansion of sandalwood in the southern region. The
phylogeographic pattern in the chloroplast genome is congruent with that detected in the nuclear
genome, which identified different genetic influences between the regions and also suggested a
more recent expansion of sandalwood in the southern region.
Byrne M., McDonald B., Broadhurst L. & Brand J. (2003) “Regional genetic differentiation in
Western Australian sandalwood (Santalum spicatum) as revealed by nuclear RFLP analysis.”
Theoretical & Applied Genetics 107(7), 1208-1214. Abstract. Western Australian sandalwood,
Santalum spicatum, is widespread in the semi-arid and arid regions of Western Australia, and
there is some morphological variation suggestive of two ecotypes. The level and structuring of
genetic diversity within the species was investigated using anonymous nuclear RFLP loci.
Santalum spicatum showed moderate levels of genetic diversity compared to other Australian
tree species. The northern populations in the arid region showed greater levels of diversity and
less population differentiation than the southern populations in the semi-arid region due to
differences in the distribution of rare alleles. Equilibrium between drift and gene flow in the
northern populations indicated that they have been established for a long period of time with
stable conditions conducive to gene flow. In contrast, the southern populations showed a
relationship between drift and gene flow indicative of a pattern of fragmentation and isolation
where drift has greater effect than gene flow. The different patterns of diversity suggest that the
ecotypes in the two regions have been subject to differences in the relative influences of drift and
gene flow during their evolutionary history.
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