An update on Lygodium microphyllum biological control

Heartland CISMA 25 February 2015 Melissa C. Smith

Ellen C. Lake Phillip Tipping

USDA-ARS Invasive Plant Research Lab Fort Lauderdale, Florida

Lygodium microphyllum in South Florida…and beyond

Lygodium in Conservation Areas

Flatford Swamp Greenswamp Wilderness Preserve

A.R.M. Loxahatchee NWR

Everglades National Park

Propagule pressure:

• Each sorus has ~ 215 spores • Each fertile leaflet has ~ 133 sori • 215 X 133 = 28,500 spores per

fertile leaflet (Volin et al. 2004)

Sori

L. microphyllum reproduction

Lygodium biological control: Moths that were, moths that are, and some moths that have not yet come to pass (and a mite)

Austromusotima camptozonale

Neomusotima conspurcatalis

Lygomusotima stria

Neomusotima releases 2008 - 2009

PresenterPresentation NotesMany of these releases are in the same locations as the Austromusotima, or white Lygodium mite that failed to establish in the field.

Neomusotima range 2012 - 2014

Neomusotima in the field

Neomusotima in the field

Neomusotima research

Feeding preference • Do N. conspurcatalis

larvae preferentially feed on fertile fronds?

• Effects of fertile frond feeding on spore germination

• Effects of fertile frond feeding on larval development time

Neomusotima research

Feeding preference • 1st and 2nd Instar

Larvae preferentially feed on fertile fronds in choice tests (p

Choice Feeding Trial

0

0.5

1

1.5

2

2.5

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3.5

4

Fertile Sterile Fertile Sterile Fertile Sterile Fertile Sterile Fertile Sterile

A A B B C C D D E E

Cm2 c

onsu

med

per

indi

vidu

al

Leaf

Fertile Sterile

a*

b*

a*

b*

No-Choice Feeding Trail

0

0.5

1

1.5

2

2.5

3

3.5

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Fertile Sterile Fertile Sterile Fertile Sterile Fertile Sterile Fertile Sterile

A A B B C C D D E E

Cm2

cons

umed

per

indi

vidu

al

Leaf

Fertile Sterile

a*

b*

a*

b*

Oviposition Preference Trial

0

20

40

60

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140

Fertile Sterile

Larv

ae p

rodu

ced

per f

emal

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Leaf Type

a*

b*

Neomusotima research

Spore germination • Passage through the

gut of the caterpillar only resulted in 2 prothalli

Neomusotima research

Development time • Fertile frond feeding

did not significantly affect larval development time or successful emergence to adult.

• Did not measure “downstream” effects in adults or larval size.

Integrated weed management

• Control • Neomusotima only • Herbicide only • Neomusotima and

herbicide

Floracarus perrepae (Eriophyidae)

Freeman et al. 2005

• Transfers of galled material 2008 – 2010 • Very low establishment success measured in

2011 • Thought to be haplotype specific? • Does wet or dry season release timing

determine establishment?

F. perrepae damage

• Australia: Goolsby et al. (2004)

• Reduced aboveground biomass by 49%

• Reduced belowground biomass by 35%

• In Florida: • Reduction of formation

of fertile fronds? • Are mite and moth

damage synergistic?

F. perrepae releases 2008

F. perrepae range 2015

Lygodium and CERP

• 300,000 N. conspurcatalis released since Q1 2014

• 60,000 F. perrepae released since Q1 2014

• Mass rearing and release of N. conspurcatalis and F. perrepae

• Follow up to determine “success” (establishment, impact, dispersal)

• Priorities given to natural areas

Future directions • Collaboration with CSIRO Australia to

investigate apparent haplotype mismatch • Determine the relative impacts of the moth

alone, the mite alone, and the two together • Build occupancy models to predict “patches”

where moths could occupy and focus releases

Acknowledgments

Southwest FloridaWater Management District

An update on Lygodium microphyllum biological controlLygodium microphyllum in South Florida…and beyondLygodium in Conservation AreasL. microphyllum reproductionLygodium biological control:Neomusotima releases 2008 - 2009Neomusotima range 2012 - 2014Neomusotima in the fieldNeomusotima in the fieldNeomusotima researchNeomusotima researchChoice Feeding TrialNo-Choice Feeding TrailOviposition Preference TrialNeomusotima researchNeomusotima researchIntegrated weed managementFloracarus perrepae (Eriophyidae)�F. perrepae damageSlide Number 20F. perrepae range 2015Lygodium and CERP Future directionsAcknowledgments