Technical highlights - Department of Primary Industries ...

11. Biological control of Hudson pear (Cylindropuntia rosea)
Project dates
October 2009 – June 2012
Project leader
Dr Bill Palmer
Ecosciences Precinct
Tel: (07) 3255 4469
Email: bill.palmer@deedi.qld.gov.au
Other staff in 2010–11
Peter Jones
Objectives
• Obtain permission to release the
cochineal insect Dactylopius
tomentosus as a biological control
agent for Hudson pear in Australia
by providing evidence of its hostspecificity
through laboratory
experimentation within quarantine.
• Determine the effectiveness of this
biotype of D. tomentosus against
various other Cylindropuntia spp.
found in Australia.
Rationale
Hudson pear (Cylindropuntia rosea)
is native to Mexico. In Australia, it
is found primarily in north-western
New South Wales, but it also occurs
in Queensland. It was approved as a
target for biological control by the
Natural Resource Management Standing
Committee in 2008. Biosecurity
Queensland has been contracted by
the New South Wales Government
Department of Primary Industries to
test the host-specificity of the cochineal
insect D. tomentosus in quarantine.
Methods
We culture the bug, care for the plants
and test for appropriate host-specificity
to ensure that the insect does not attack
any native or economically desirable
plant. We also evaluate the efficacy
of the insect against other weedy
Cylindropuntia spp. found in Australia.
If testing determines that the insect
is safe to release in Australia, the
appropriate permissions will be obtained
from regulatory authorities to enable its
release from quarantine.
Photo 11.1 A male D. tomentosus fertilising a mature female (hidden underneath waxy secretion)
Our collaborators in New South Wales
source the culture, test plants, design
experiments in consultation with us,
arrange for mass-rearing and release
of the bug in the infested areas of New
South Wales and write reports.
Progress in 2010–11
In August 2010, collaborator Dr Carla
Chavez Moreno hand-carried a
population of D. tomentosus collected on
the required host C. rosea to Australia,
where it was placed in quarantine.
However, the insect could not use
Australian populations of Hudson pear
nor other Cylindropuntia spp. presently
found in Australia. The culture was
maintained on Mexican cladode material
for many months but all attempts to rear
it on Australian material failed.
We are now attempting to culture
other populations of D. tomentosus:
a population infesting C. kleiniae was
obtained from South Australia and
host testing commenced; a population
currently giving effective biological
control of C. fulgida in South Africa will
also be imported.
We have also arranged for genetic
studies to be undertaken on C. rosea
from Mexico and Spain, C. fulgida
from South Africa and most of the
Australian Cylindopuntia spp. in order
to have an improved understanding
of the taxonomy of this genus.
Given the problems encountered with
D. tomentosus from Mexico, the question
remains whether Hudson pear in
Australia is really C. rosea or perhaps a
hybrid. Linking our Hudson pear with
similar genotypes in Mexico would
also enable appropriate native range
collections of D. tomentosus.
Funding in 2010–11
New South Wales Government
Department of Primary Industries
($31 000)
Collaborators
• Royce Holtkamp (New South Wales
Government Department of Primary
Industries)
• Catherine Mathenge (University of
Western Sydney)
• Carla Chavez Moreno (University of
Michoacan, Mexico)
• Mayra Pérez and Sandi Cuen
(Aridamerica AC, Mexico)
• Helmuth Zimmermann (Helmuth
Zimmermann & Associates,
South Africa)
More information
For further information on this
research project, visit the invasive
plant and animal science pages on the
Biosecurity Queensland website at
www.biosecurity.qld.gov.au
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