The extended phenotype of Eucalyptus globulus B Potts 1 , R Barbour - - PowerPoint PPT Presentation

The extended phenotype of Eucalyptus globulus

B Potts1, R Barbour1, J O’Reilly-Wapstra1, S Baker2, L Forster1, J Schweitzer3, J Bailey3, T Whitham4, J Humphreys1, J Freeman1 and R Vaillancourt1

1School of Plant Science and CRC for Forestry, University of Tasmania, Australia 2School of Zoology and CRC for Forestry, University of Tasmania, Australia 3Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, USA 4Department of Biological Sciences & the Merriam-Powell Center for Environmental Research, Northern

Arizona University, USA

The extended phenotype

from Whitham et al. 2006

“The effects of genes at levels higher than the population”

(Dawkins 1982; Whitham et al. 2003)

Foundation species

Dominant or keystone species that have a disproportionate influence on the ecosystem in which they occur

Trees as foundation species

Populus in USA

Whitham et al 2003, 2006

• Conservation and management
• f biodiversity
• Restoration ecology
• Predict the broader impacts of

anthropogenic changes (e.g. GMOs)

• Community structure & evolution

• Dominant of lowland forest in SE

Australia and Tasmania

• A major plantation species in

temperate regions of world

• Extensive genetic resources available
• Extensive quantitative and molecular

studies of gene pool

The case of Eucalyptus globulus

Significant spatially structured genetic variation in numerous traits

Dutkowski & Potts 1999

9% 3% 9% 5% 74%

residual race locality family block genetic 21% genetic + environmental

8% between plots 8% between plots 68% within two-tree plots

Partition of variation within Gunns Ltd trials

(46 traits, 13 races, 46 localities, 450+ families)

Localities from the1987/88 CSIRO range-wide collection of 600+ OP seedlots and racial classification

Potts et al. 2004

5 trials

Dependent herbivores respond to genetic variation in tree traits

Sawfly (Perga affinis)

Foliage damage greater

• n thick barked trees

(rg = 0.44 ***)

Dutkowski & Potts 1999 Jordan et al. 2002 Kelly 1997

Oviposition is affected by genetic variation in the aliphatic ester (C24) benzyl n-tetracosanoate

Jones et al. 2002 Rapley et al. 2004a,b,c

Autumn gum moth (Mnesampela privata)

O’Reilly-Wapstra et al. 2002, 2004, 2005a,b

Brush tail possum

Foliage intake is affected by genetic variation in formylated phloroglucinol compounds (FPCs) [sideroxylonal A and macrocarpal G ]

Significant racial differences in defensive chemistry

Adult foliage condensed tannins

O’Reilly-Wapstra et al. submitted

How far does the effect of genetic variation at the race level flow through the ecosystem?

The experiment

• 1. 160 felled trees
• age 15 years
• 8 races across 2 replicates
• 20 trees per race (10 families per race, 2 trees/ family)
• 2. 100 standing trees
• age 16 years
• 5 races across 2 replicates
• 20 trees per race (10 families per race, 2 trees/ family)

Gunns Ltd E. globulus base population field trial at West Ridgley, NW Tasmania (CSIRO 1988/89 OP seedlots)

Defining the extended phenotype

Canopy & leaf decay rates & communities Log & disc decay rates & communities (invertebrates, fungi) Seedling recruitment Chemical and nutrient leaching into soil

Genetic variation

CHO HO OHC OH O OH CHO HO OHC OH O OH

Bark communities Soil nutrients & micro-biota (invertebrates) Tree canopy communities (fungi, invertebrates, marsupials, [birds],)

5 10 15 EO FI KI SET ST Strz WO WT

Radicle length (mm)

20 30 40 50 60 EO FI KI SET ST Strz WO WT

% germination

%

% germination radical length

length (mm)

Linseed bioassay of soil extracts taken from beneath decaying canopies after 7 months

Race of decaying canopy can affect soil quality

Race of decaying canopy affects litter invertebrate community

Pitfall traps beneath decaying canopies of trees from Southern Tasmania and Strzelecki Ranges

Abundance

Non-collembolan invertebrates 60 110 160

n individuals Species richness

Total invertebrates 20 35 50

n species

Significant (P<0.05) variation in community traits was found

S Tas Strzelecki S Tas Strzelecki

○ Southern Tasmania ▲ Strzelecki Ranges

Community NMDS ordination

Tree race affects soil nutrient availability

Resin bags at base of tree

NO3 levels in soil at base of standing trees

Provenance

NO

– 3 (ug/g OD resin/d)

0.0 0.5 1.0 1.5 2.0 2.5

Flinders Is. Jeeralong NE Tas Southern Tas Westerrn Tas

a b ab ab

Race

Strzelecki NE Tas S Tas W Tas

ab a b ab ab

Flinders Island

All loose bark & associated invertebrates removed from the trunk

• f 100 trees

30-50% of individuals are spiders and other predators

Tree race affects bark community

Species abundance

20 40 60

STRZ FI NE TAS S TAS W TAS

n individuals a b b b b

Bark retention

2 4 6

Flinders Island Northeast Tasmania Southern Tasmania Western Tasmania a c c

a c bc ab c Height (m)

…

Race Arthropod abundance Height of loose bark

Conclusion

There is increasing evidence for extended community and ecosystem effects of genetic variation at the racial level in E. globulus, but their stability and extent are as yet unclear. Community and ecosystem genetics is an emerging field in ecology. Forest trees are key study organisms and studies will increasingly focus on lower levels of genetic variation with community heritability H2c/ h2c estimates and QTLc studies appearing.

Thank you

Photo: S Foster

We thank the Gunns Ltd and Forestry Tasmania for inkind support and access to field trials Funding is provided by Australian ARC Discovery and USA National Science Foundation FIBR grants

References

Dutkowski GW, Potts BM (1999) Geographic patterns of genetic variation in Eucalyptus globulus ssp. globulus and a revised racial

• classification. Australian Journal of Botany 47, 237-263.

Jones TH, Potts BM, Vaillancourt RE, Davies NW (2002) Genetic resistance of Eucalyptus globulus to autumn gum moth defoliation and the role of cuticular waxes. Canadian Journal of Forest Research 32, 1961-1969. Jordan GJ, Potts BM, Clarke AR (2002) Susceptibility of Eucalyptus globulus ssp globulus to sawfly (Perga affinis ssp insularis) attack and its potential impact on plantation productivity. Forest Ecology and Management 160, 189-199. Kelly CM (1997) Natural variation and genetic control of relative bark thickness in Eucalyptus globulus ssp. globulus. BSHonours thesis, University of Tasmania. O'Reilly-Wapstra JM, McArthur C, Potts BM (2002) Genetic variation in resistance of Eucalyptus globulus to marsupial browsers. Oecologia 130, 289-296. O'Reilly-Wapstra JM, McArthur C, Potts BM (2004) Linking plant genotype, plant defensive chemistry and mammal browsing in a Eucalyptus

• species. Functional Ecology 18, 677-684.

O'Reilly-Wapstra JM, Potts BM, McArthur C, Davies NW, Tilyard P (2005) Inheritance of resistance to mammalian herbivores and of plant defensive chemistry in an Eucalyptus species. Journal of Chemical Ecology 31, 357-375. O'Reilly-Wapstra JM, Potts BM, McArthur C, Davies NW (2005) Effects of nutrient variability on the genetic-based resistance of Eucalyptus globulus to a mammalian herbivore and on plant defensive chemistry. Oecologia 142, 597-605. Potts, B.M., Vaillancourt, R.E., Jordan, G., Dutkowski, G., Costa e Silva, J. McKinnon, G., Steane, D., Volker, P., Lopez, G., Apiolaza, L., Li, Y. Marques, C. and Borralho, N. (2004). Exploration of the Eucalyptus globulus gene pool. Plenary paper In ‘Eucalyptus in a changing world’ (Eds. N.M.G. Borralho, J.S. Periera, C. Marques, J. Coutinho, M. Madeira and M. Tomé) pp. 46-61. Proc. IUFRO Conf., Aveiro, 11-15 Oct. 2004 (RAIZ, Instituto Investigação de Floresta e Papel, Portugal). Rapley, L, Allen, GR & Potts, BM (2004). Oviposition by autumn gum moth (Mnesampela privata) in relation to Eucalyptus globulus defoliation, larval performance and natural enemies. Agricultural and Forest Entomology 6, 205-213 Rapley LP, Allen GR, Potts BM (2004) Genetic variation of Eucalyptus globulus in relation to autumn gum moth Mnesampela privata (Lepidoptera: Geometridae) oviposition preference. Forest Ecology and Management 194, 169-175. Rapley LP, Allen GR, Potts BM (2004) Susceptibility of Eucalyptus globulus to Mnesampela privata defoliation in relation to a specific foliar wax

• compound. Chemoecology 14, 157-163.

Whitham TG, Bailey JK, Schweitzer JA, Shuster SM, Bangert RK, LeRoy CJ, Lonsdorf E, Allan GJ, DiFazio SP, Potts BM, Fischer DG, Gehring, CA, Lindroth RL, Marks J, Har SC, Wooley SC and Wimp, GM. (2006) Community and ecosystem genetics: a framework for integrating from genes to ecosystems. Nature Reviews Genetics 7, 510-523. Whitham TG, Young WP, Martinsen GD, Gehring CA, Schweitzer JA, Shuster SM, Wimp GM, Fischer DG, Bailey JK, Lindroth RL, Woolbright S, Kuske CR (2003) Community and ecosystem genetics: A consequence of the extended phenotype. Ecology 84, 559-573.