Pathways of invasion by forest pests and pathogens
Alberto Santini
Luisa Ghelardini, Nicola Luchi, Duccio Migliorini, Francesco Pecori, Alessia Pepori
Institute of Plant Protection ‐ CNR, Firenze, Italy
Before 7000 B.C.
7000-6000 B.C.
Historical milestones
6000-5000 B.C.
5000-3800 B.C.
3800-2500 B.C.
• 1492 Discovery of America;
•1819 First steamboat crossed Atlantic ocean;
• 1945 End of WWII and rise in trade between North America,
Europe, and Asia;
• 1989 Fall of Berlin wall.
modified from Zohary and Hopf, 1993
New risks:
1.Liberalization of trade;
2.Boundaries opening;
3.Innovations in transportation increase the
speed of spread;
4.Global change.
Total established forest pathogens
50
45
y = 2,0691e0,4345x
R² = 0,8938
40
35
30
25
20
15
10
5
0
1800‐29
1830‐59
1860‐89
1890‐1919
1920‐49
1950‐79
Santini et al., New Phytol. in press
Hulme et al., 2009
Roques, BioRisk 4: 11–26 (2010)
1980‐2008
An increasing problem
Roques, 2010
Drivers of plant EIDs emergence
Change in vector
population
7%
Recombination
2%
Habitat
disturbances
1%
Farming techniques
9%
Introductions
56%
Weather
25%
(mod. from Anderson et al., 2004. Trends Ecol Evol. 19: 535-544)
Pathogens causing plant EIDs
Nematods
1%
Phytoplasma
4%
Bacteria
16%
Virus
47%
(mod. from Anderson et al., 2004. Trends Ecol Evol. 19: 535-544)
Unknown
2%
Fungi
30%
Worldwide reporting trends in fungal EIDs.
MC Fisher et al. Nature 484, 186-194 (2012) doi:10.1038/nature10947
1938
1951
Ceratocystis platani (J.M. Walter) Engelbr. & T.C. Harr. 2005
1971
16
Status of forest pathogens
Alien
14
Cryptogenic
12
European
Hybrid
10
8
6
4
2
1980‐
2008
1950‐79
1920‐49
1890‐
1919
1860‐89
1830‐59
1800‐29
0
Santini et al., (in press)
New pathogens: the rise of hybrids
Genus
Order
Host and disease
Place
Date
Melampsora
Bm
Poplar rust
New Zealand,
South Africa
1994
Heterobasidion
Bm
Conifers rot
USA California
1996
Ophiostoma
Am
Dutch elm disease
Europe, Asia SWest
1998
Phytophthora
Om
Primula e Spathiphyllum
The Netherlands
1998
Root rot
Phytophthora
Om
Alder disease
Europe
1999
Melampsora
Bm
Poplar rust
USA N-West
2000
Heterobasidion
Bm
Conifers rot
Italy
2011
(mod. from Brasier, 2000. Nature 405:134-135)
Ophiostoma novo-ulmi
1970
Amount of Invasive P&P per country
-
Forest pests (Roques, 2010)
+
Forest pathogens (Santini et al. in press)
Origin of established pest and pathogens
Unknown 7%
Australasia 5,5%
Phytophagous
species
North America 26,7%
Australasia 1 %
Africa 4 %
Pathogen
species
Asia 19 %
Unknown 38 %
Asia 30,0%
Central America 2 %
South America 12,3%
Tropical 5,3%
Hybrid 6 %
North America 30 %
Africa 13,2%
Forest pests (Roques, 2010)
Forest pathogens (Santini et al. in press)
10
Australasia
9
Africa
8
Asia
7
Trop N America
6
Temp N America
5
4
Origin of forest pathogens
Hybrid
Europe
3
2
1
1980‐2008
1950‐79
1920‐49
1890‐1919
1860‐89
1830‐59
1800‐29
0
Santini et al., (in press)
Most‐likely pathways of introduction of forest pathogens in Europe
Unknown
17 %
Wood packaging
2%
Air-borne
21 %
Tourism
4%
Tools
1%
Host jump
4%
Hybrid
3%
Vectors
2%
Trade
46 %
Santini et al., in press
Most likely pathways of alien pathogens and pest
species in Europe
Phytophagous
species
Greenhouse escapes
13 %
Crops
4 %
Forestry
6 %
Hitch‐hikers
6 %
Other
products
13%
Leisure
1 %
Horticultural
/Ornamenta
l
30 %
Forest pests (Roques, 2010)
Living plants 53%
Unknown
27 %
Pathogen
species
Unknown
12 %
Bark
7 %
Cuttings
Seeds 4 %
1 %
Wood
10 %
Soil
9 %
Living plants
57 %
Forest pathogens (Santini et al. in press)
Most likely pathways and vectors of insects in Austria and Switzerland. Kenis et al., Bull Entomol Res (2007) 97, 489–502
Entry pathways of plant pest established in Great Britain
1,80%
2,80%
3,70%
0,90%
1,80%
Movement of plants
Apiculture
Biocontrol
Intentional releases
Timber imports
Transport stowaways
89%
mod. from Smith et al., Agric For Entomol (2007), 9, 307–326
Pathways of invasion for forest insects and pathogens in the US
Live plants
Hitchhiker
Wood
Other or unknown
20 %
29 %
3 %
47 %
5 %
72 %
Forest insects
24 %
Forest pathogens
Liebhold et al., 2012. Front Ecol Environ 10(3):135‐143
Invaded environments
Pathogens - Europe
Pests – Great Britain
1 %
2% 3%
1 %
1 %
5 %
21 %
36 %
15 %
43 %
34 %
38 %
Forests
Ornamental
Nursery
Other plantations
Orchards
Ornamental
Uncultivated habitats
Under cover
Forestry
Agriculture/horticulture
Apiculture
Unknown
Santini et al., New Phytologist, in press
Smith et al., 2007 Agric For Entomol 9: 307–326
Insect
Pathogen
Host
Alien species use ancient fungus‐insect associations
Orsillus maculatus
Seiridium cardinale
Leptoglossus occidentalis
Diplodia pinea
Cupressus sempervirens
Pinus spp.
Insect
Pityophthorus spp.
Scolytus scolytus
Pathogen
Fusarium circinatum
Ophiostoma ulmi s.l.
Host
Pinus spp.
European elms
A warming climate, risks and opportunities
Spread
(invasion stage)
Establishment
(naturalization)
Climate change enhances the competitive ability of established alien species and extends suitable areas, which might offer new opportunities for introductions.
Climate change enables successful reproduction and establishment of alien species.
Colonization
(casual stage)
Climate change increases the success of survival and enables better growth of alien species in the introduced range.
Introduction
Climate change facilitates transport through
higher intensity and/or frequency of extreme
events and opens new areas for setting. (modified from Walther et al., 2009)
From Didham et al. ,2005. TRENDS in Ecology and Evolution 20 (9)
Consequences of climate change for invasive species (Hellmann et al., 2008)
1.
2.
3.
4.
5.
Altered transport and introduction mechanisms;
Establishment of new invasive species;
Altered impact of existing invasive species;
Altered distribution of existing invasive species;
Altered effectiveness of control strategies.
The European network on emerging diseases and invasive species threats to European
forest ecosystems.
Increasing Sustainability of European Forests:
Modelling for security against
invasive pests and pathogens under climate change
EU COST Action FP1002
PERMIT ‐ Pathway evaluation
and pest risk management in transport
Ophiostoma ulmi
1912-’13
Aliens always favoured ?
Expansion model of pine wood nematode in China with warming up and man activity
Potentially favourable
areas according to
normal temperatures
over 1951-1980 (dark
red), and 3°C of
temperature increase
(dark + light red):
potential expansion
area
Invasion
probability predicted
by the dispersal model
in 2005
Not many
differences !
in 2025 under the
assumption
of a stable climate
in 2025 under the
assumption of a
constant warming
(+0.03°C/yr)
Robinet et al., PLoS 2009