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Bellyache bush in the native range on the shore of Lake
Managua
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An adult of Agonosoma trilineatum the first biocontrol
agent of bellyache bush
Photo: T Heard
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Background
Bellyache bush, Jatropha gossypiifolia (Euphorbiaceae)
is a serious emerging weed of Northern Australia. It invades
rangeland particularly in riparian zones, forming dense thickets
which eliminate useful species, reduces productivity and hinders
mustering. All parts of the plant especially the seeds are
toxic and ingestion causes the deaths of grazing animals,
a problem that occurs especially during drought. In the Weeds
of National Significance prioritising exercise, bellyache
bush was rated as number 21. The standing committee on Agriculture
and Resource Management has endorsed the weed as a target
for biological control. It is native to the American Tropics
but has become widely naturalized elsewhere in the tropics
where it has been introduced as an ornamental and medicinal
plant.
The Project
Surveys of the natural enemies have been conducted in the
native range of this weed: tropical America and the Caribbean.
Surveys are one of the first steps in a biocontrol project
and include the collection, rearing, curation, identification,
and cataloguing of the natural enemies. Eight countries in
the native range of this weed have been visited. Searches
have been made at a total of 177 locations. Some of these
locations have been visited multiple times to generate 220
collection events. Thousands of insect specimens have been
collected and sent for identification. A relational database
has been designed and all data has been entered for secure
storage, and querying. A preliminary list of phytophagous
insects has been compiled consisting of 60 species in 21 families
and four orders. One species of fungus has also been collected.
Higher priority potential agents have been identified according
to their abundance and the damage that they inflict in the
native range. The most promising agent proved to be the seed
feeding Scutelleridae Agonosoma trilineatum. This insect
was first released in 2002 in Queensland and the Northern
Territory, the first biocontrol agent of this weed to be used
anywhere in the world. Preliminary studies on the rust fungus,
Phakopsora jatrophicola indicate potential as an agent.
Several lines of evidence suggest that the prospects for
biological control of bellyache bush are good. Firstly, there
is a moderately large suite of natural enemies attacking this
plant in the native range. Second, the plant is less vigorous
in the native range and we attribute this to herbivory. Thirdly,
no plant species in the tribe Jatropheae occur naturally or
are economically important in Australia.
This weed is also a serious problem in East Timor and east
Indonesia. These countries would benefit from the extension
of Australian research activities. Bellyache bush has been
included in the CRC for Australian Weed Management as a case
study of an invasive rangeland shrub.
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A Bellyache bush infestation in Queensland
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Collaborators
Close cooperation between CSIRO and Qld DNRME and NT government
weeds branch has been a feature of this project. The biological
control work described here has been conducted by CSIRO with
funding input from DBIRD and DNRM. DNRM have simultaneously
been working on other management options. The mass-rearing
and release of the agents that have been approved for release
is being done by DNRM and DBIRD. Evaluation of the impact
of the agents will also be done by DNRM and has already commenced
with baseline ecological parameters being collected for comparison
with data after the agents are established and damaging plants.
DBIRD has provided species of Euphorbiacae for host testing
insects and cuttings of bellyache bush for insect cultures
in Brisbane. CABI BioScience, UK, assisted with pathogen work.
Key People
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Tim Heard
CSIRO Entomology
Tropical Weed Management
Long Pocket Laboratories
Indooroopilly QLD 4068
AUSTRALIA
Ph: +61 7 3214 2200
Fax: +61 7 3214 2885
Email: firstname.lastname@csiro.au
Richard Chan
CSIRO Entomology
Tropical Weed Management
Long Pocket Laboratories
Indooroopilly QLD 4068
AUSTRALIA
Ph: +61 7 3214 2200
Fax: +61 7 3214 2885
Email: firstname.lastname@csiro.au |
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Ricardo Segura
CSIRO Mexican Field Station
A. Carlon no. 5, Ejido 1 de Mayo
Boca del Rio
Veracruz, CP 94297
MEXICO
Ph: 0011 52 2 9213704
Fax: 0011 52 29 213701
Email: firstname.lastname@csiro.au |
Publications
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Heard, TA, Chan, RR and Segura R. (2002) Prospects for
the biological control of bellyache bush, Jatropha
gossypiifolia. 13th Australian Weeds Conference:
Papers and Proceedings: 8-13 September 2002, Perth,
WA. Pp: 366-369.
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Smith, K. and Heard, T (2003) Biological Control of
the bellyache bush. Pesticide Outlook 14: 145.
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Heard, T (2003) Soothing the pain of bellyache bush.
Weedwatch Newsletter of the Cooperative Research
Centre for Australian Weed Management 2: p 6.
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Heard, T.A. and Chan, R.R. (2002) Application to release
Agonosoma trilineatum (Heteroptera: Scutelleridae)
a biological control agent of the weed Jatropha gossypiifolia
(Euphorbiaceae), unpublished application to AQIS.
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Heard, T.A. (2002) Workshop Report Bellyache bush (Jatropha
gossypiifolia). Unpublished Report.
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