1. Population biology of Beauveria Dave Chandler, Gill Davidson University of Warwick
Insect pathology -
the early years

2. Anamorphic Ascomycete Entomopathogenic fungi
Widespread in nature, especially soil.
Range of species, different properties.
Used as inundative biopesticides.
Can be valuable components of IPM.

3. Chemical clones or bio-control agents?
Inundative biopesticides: development = chemical model.
Ignoring ecological attributes (Waage)
numerical response,
trade offs,
conservation control.
Lack of knowledge: affects biocontrol efficacy & environmental risk evaluation.

4. Ascomycete entomopathogenic fungi
Natural abundance? Diversity? Ecosystem function?
Are they ecologically obligate pathogens?
Determinants of population structure?
Population dynamics?
How does virulence evolve?
Lack meaningful species definitions.
Theoretical framework for predicting environmental (non target) impacts of biocontrol releases.

5. Work outline
Studying natural popns. of fungi in soils, esp. Beauveria.
Bidochka : biogeography of Beauveria & Metarhizium.
Rehner: Beauveria phylogeny.
Expt 1:
Examined Beauveria from culture collection: collected from UK woodland & farm grassland.
Expt 2:
Sampling at a single farm site.

6. Galleria bait method

7. Experiment 1: Beauveria biogeography?: national scale
Culture collection: Beauveria isolates from 9 woods & 11 grasslands.
Devon
Somerset
Gloucestershire
Herefordshire
Shropshire
Berkshire
Warwickshire
Leicestershire

8. Beauveria biogeography: national scale
Culture collection:
Isolates from each location.
117 total, 85 wood, 32 grass.
Sequence data:
EF1a
28s rDNA gp I intron
Beta tubulin, rDNA ITS
DNA lyase, Beta locus
Micro satellites.

9. EF1a woods & grassland A :28/56 from woods (exp 41/56)
(includes 1 sequence each from Rehner clades A – F)
B. scarabaeicola EFCC2533
A :28/56 from woods (exp 41/56)
100 63 98 88
B: 20/20 from woods (exp 15/20)
C: 37 / 41 from woods (exp 30/41)
D (B. caledonica) none
E (Cordyceps sp.) none
clustal W, distance (NJ)
F (B. amorpha) none
Chi sq : habitat effect : p < (pearson = 28, 2 df)

10. Expt 2: Fungi from different habitats in close proximity: Warwick Dept
Expt 2: Fungi from different habitats in close proximity: Warwick Dept. farm
Grassland
10 ha
Stewardship
12 ha
Arable
7 ha
hedgerow

11. Expt 2: Fungi from different habitats in close proximity
Water meadows
Long close
Deep slade

12. Frequency of occurrence (%)
samples
Beau
Met
P. fa
P. fu
Lec
arable
506 16 1
steward
240 28
0.5
grass
150 55 2
hedge
250 34 5 11
all
1146
0.6 3
0.3
Chi square (pearson) 68.7, 9 df, p < 0.001

13. Constructed tree (NJ, distance) with Beauveria isolates: Hedgerow 24
EF1a Warwick dept farm
Constructed tree (NJ, distance) with Beauveria isolates:
Hedgerow 24
Arable 26
Stewardship 23
Grassland 26
Total 99

14. EF1a Warwick dept. farm: hedge vs. fields
(includes 1 sequence each from Rehner clades A – F)
B. scarabaeicola EFCC2533
A :7/77 from hedge (exp 19/77) 96 64
100
B: 1/2 from hedge
100 97
C: 16 / 20 from hedge (exp 5/20)
100
D (B. caledonica) none
100
E (Cordyceps sp.) none
clustal W, distance (NJ)
F (B. amorpha) none
Chi sq : habitat effect : p < (pearson = 47, 6 df)

15. Simplified conclusions
Genetic groups in Beauveria have different habitat preferences. Why?
Warwick farm study:
Habitat type affects frequency of occurrence of fungi.
Diff genera have diff habitat preferences?

16. Why does this matter?
Bio-prospecting.
Conservation control (habitat manipulation).
Informs risk assessment.
Generation & maintenance of diversity in an ‘asexual’ organism.

17. acknowledgements
USDA Steve Rehner

18. Thanks for your attention!