Tradescantia
(Tradescantia fluminensis)
Tradescantia
(Tradescantia fluminensis)
• Native to South America
• A serious weed in a number of
places around the world including
New Zealand, Australia and the
USA.
.......but it can also earn valuable overseas
dollars!
Photo of Miserablelooking Plant
Photo from South America
Surveys for potential biocontrol
agents began in Brazil in 2005
Tradescantia grows best on the slopes of
the Brazilian Highlands plateau at altitudes
between 600 – 900 m
Surveys identified a rich natural
enemy biota including herbivorous
insects and plant pathogens.
yellow leaf
spot fungus
Thrips
Leaf mining moth
Sawfly
Neolema abbreviata – “stripy”
Neolema ogloblini
Growing stems
with leaves
Lema basicostata – “knobbly”
Dense mat of
live stems
without leaves
Thin, short roots
Buckibrotica cinctipennis
Initial agent selection included 4
beetles with complementary larval
feeding methods
Host range testing
• Thorough host range testing to assess
risk to non-target plants
• No native New Zealand plants in the
family Commelinaceae or the order
Commelinales
• Closest NZ relative to Tradescantia is
the nikau palm
.
ERMA granted permission to release
the first beetle in 2008
The Tradescantia Leaf Beetle
(Neolema ogloblini)
Gregarine Parasite
• Leaf beetle releases delayed because of a
Gregarine parasite
• Sporozoan Protozoan
• Although a common life form not much
work has been done on Gregarines
• We cannot release diseased bio-control
agents
Removal of gregarines from
N. ogloblini populations
Egg Surface Sterilisation
Washing eggs in bleach
(Sodium Hypochlorite)
Line Rearing Neolema ogloblini
Parent colony
Individual
female
F2
F3
F1
Individual
Individual
Individual
egg to adult egg to adult egg to adult
December 2010
Tradescantia Leaf Beetle Releases
Releases began March 2011
10,000 adults at 31 sites
• A generation in about 8 weeks in
warm temperatures
• May get through 3 generations
per year
Permission to release the stem boring beetle and
the tip beetle was granted by ERMA in June 2011 –
but they were also infected with Gregarines
Lema basicostata
(stem borer)
Neolema abbreviata
(tip feeder)
Released From Quarantine
November 2011
- 24 tip feeders
- 207 stem borers
Tradescantia Stem Borer Releases
• Releases began
February 2012
• 1262 adults
released at 6 sites
• A generation in about 8 weeks in
warm temperatures
• May get through 3 generations
per year
Tradescantia Tip Beetle
(Neolema abbreviata)
24 from quarantine last November
Releases planned
For Spring 2012
Buckibrotica cinctipennis
-
Stem borer
-
Difficult to rear
-
On hold for now
Yellow Leaf Spot Fungus
(Kordyana tradescantae)
Yellow Leaf Spot Fungus
Kordyana tradescantae
Our colleagues in Brazil have finished host-range testing of
the fungus and confirmed that it will attack only
Tradescantia fluminensis.
An application to the EPA (Environmental Protection
Authority) to import and release the fungus is now being
prepared.
If permission is granted by the EPA the fungus will be
imported into our new pathogen quarantine facility.