View
213
Download
0
Category
Preview:
Citation preview
Recent Progress in Researches Recent Progress in Researches in Japanese Oak Wilt in Japanin Japanese Oak Wilt in Japan
Naoto KAMATANaoto KAMATA
Laboratory of EcologyLaboratory of EcologyGraduate School of Natural Science and TechnologyGraduate School of Natural Science and TechnologyKanazawa UniversityKanazawa University
kamatan@kenroku.kanazawakamatan@kenroku.kanazawa--u.ac.jpu.ac.jp
2/22
JOW occurred occasionally after 1930s.JOW occurred occasionally after 1930s.JOW has been prevalent since late 1980s: It JOW has been prevalent since late 1980s: It occurred and spread every year.occurred and spread every year.The disease complex consists of the ambrosia beetle, The disease complex consists of the ambrosia beetle, Platypus Platypus quercivorusquercivorus ((MurayamaMurayama) and the ) and the AscomyceteAscomycete fungus fungus RaffaeleaRaffaelea quercivoraquercivora that coexist that coexist in a symbiotic relationship.in a symbiotic relationship.This disease is widely recognized as the only This disease is widely recognized as the only example of an ambrosial fungus vectored by an example of an ambrosial fungus vectored by an ambrosia beetle that kills vigorous trees.ambrosia beetle that kills vigorous trees.
04 AUG 2001Mt. Kariyasu, Ishikawa, Japan04 AUG 200104 AUG 2001Mt. Mt. KariyasuKariyasu, Ishikawa, Japan, Ishikawa, Japan
Oak Mortality Caused by JOWOak Mortality Caused by JOW
3/22
Frass coming out from the trunk surface of a deciduous oak. (July, 2000. Mt. Kariyasu, Ishikawa, Japan)
5/22
5mm
Platypus Platypus quercivorusquercivorus ((MurayamaMurayama))
Female carries spores of ambrosia fungiFemale carries spores of ambrosia fungi
MF
Aduts
MycangiaMycangia
Raffaelea quercivoraPhoto by Shin-ichiro Ito
6/22
Inoculation Experiment of Inoculation Experiment of R. R. quercivoraquercivora to Oak Treesto Oak Trees
Photos by Shin-ichiro Ito, Mie University
7/22
pupal cell horizontal gallery
entry hole
After Kinuura (1994)
Mechanism of JOWMechanism of JOW
Insect attackInsect attackDevelopment of the Development of the fungusfungusNecrosisNecrosisNecrosis
InfestedInfested
UninfestedUninfested
Water conductance Water conductance will stopwill stop
Heartwood
Necrosis
BarkCambium
Sapwood
Tree Mortality
8/22
Mortality of Trees Newly Mortality of Trees Newly Attacked by Attacked by P. P. quercivorusquercivorus
Other reportsOther reportsMortality is higher in Qc than in Qs (Mortality is higher in Qc than in Qs (NishigakiNishigaki et al. 1998, et al. 1998, Inoue et al. 1998).Inoue et al. 1998).The mortality of evergreen oaks are generally low (<10%) The mortality of evergreen oaks are generally low (<10%) (e.g. (e.g. SueyoshiSueyoshi 1990).1990).
Q. crispula is most susceptible to R. quercivora.
0
10
20
30
40
50
Qc Qs Qa Qsa Cc
19981999
Mor
talit
y
%
Tree Species
Qc: Quercus crispulaQs: Quercus serrataQa: Quercus acutaQsa: Quercus salicinaCc: Castanopsis cuspidata
9/22
Among Tree Species Difference in Reproductive Among Tree Species Difference in Reproductive Success and Tree Preference of Success and Tree Preference of P. P. quercivorusquercivorus
Q. Q. crispulacrispula is the is the most suitable most suitable living host for living host for reproduction of reproduction of P. P. quercivorusquercivorusQ. Q. crispulacrispula was was preferred least by preferred least by P. P. quercivorusquercivorus..
Year
0
20
40
60
80
100
1998 1999 20001997
Q. serrata
Q. crispula
C. cuspidata
Q. acuta
All Fagaceae trees
%Trees in
fested b
y P. quercivorus
Q. acutaQ. serrata
Q. crispulaC. cuspidata
01234
n= 222n= 189
n= 356
n= 310
a
b c b
Rep
rod
uctio
n rate
10/22
CoevolutionCoevolution of Treeof Tree--FungusFungus--InsectInsectQ. Q. crispulacrispula isis
most susceptible to R. quercivora.the most suitable living the most suitable living host for reproduction host for reproduction of of P. P. quercivorusquercivorus..preferred least by preferred least by P. P. quercivorusquercivorus..
Distribution of P. quercivorus
Other oaks resistant to the Other oaks resistant to the fungus evolved under a fungus evolved under a stable relationship between stable relationship between tree, fungus and beetle tree, fungus and beetle during a long evolutionary during a long evolutionary process. process. Q. Q. crispulacrispula was probably was probably not part of this not part of this coevolutioncoevolution..
Q. salicinaQ. crispula Q. serrata Castaneacrenata
Q. acuta Castanopsiscuspidata
JOW & Climate Change JOW & Climate Change
Warm climate since the late 1980s was the likely Warm climate since the late 1980s was the likely cause of expansion of JOW in Japan, which made cause of expansion of JOW in Japan, which made the fateful encounter of the fateful encounter of P. P. quercivorusquercivorus with with Q. Q. crispulacrispula by pushing the distribution of by pushing the distribution of P. P. quercivorusquercivorusto a more northern and higher place.to a more northern and higher place.
Warming
North
South
Vertical distribution of Q. crispula
Vertical distribution of JOW incidence
Overlapping!
13/22
Spreading PatternSpreading Pattern
<1980
1980s
1990s
After 1980s, JOW spread concentrically, which is a typical pattern of range expansion of invasive species.Four foci, indicating that there was at least 4 times of independent introductions.
Until 1980, incidence of JOW was restricted to small numbers of locations.
14/22
Spreading Rate at a Regional ScaleSpreading Rate at a Regional Scale
Ishikawa
Fukui
Shiga
Yamagata
Niigata
Tottori HyogoKyoto
(Ito & Yamada1998)
1.9 km/yr
1.9 km/yr
2.3 km/yr
3.1 km/yr
19971998
20002002
60 km=5 years
12 km/yr
Ishikawa Pref.Toyama Pref.
Insect Flight and Winds Insect Flight and Winds
0
50
200
0
50
150
wind
Male Female
Rayleightestp<0.001
V-testp<0.001
Rayleightestp<0.001
V-testp < 0.001
Wind-vane trap
P. P. quercivorusquercivorus adults tend to move to downwind.adults tend to move to downwind.
windinsects insects
16/22
Spreading Rate and WindsSpreading Rate and Winds
JOW spread faster to eastward because JOW spread faster to eastward because most beetles fly most beetles fly downwindsdownwinds and because and because west wind is prevailing.west wind is prevailing.
0 50 100km0 50 100km
?
2.5 km/yr
Wind
0.3 km/yr
N
S
W E
Spreading Pattern of JOW at a Landscape Level Spreading Pattern of JOW at a Landscape Level
? ? ? ? ?
0 250 500 m0 250 500 m0 250 500m
19971998
19992000
18/22
Distance between new Distance between new occurrence of JOW and the occurrence of JOW and the nearest trees that had been nearest trees that had been killed in the past killed in the past
0
200
400
600
800
1000
010
020
030
040
050
060
070
080
090
010
00
Distance (m)
Fre
qu
ency
distance of damage in 1998 from damage in 1997
0100200300400500600700800900
1000
010
020
030
040
050
060
070
080
090
010
00
Distance (m)
Fre
qu
ency
distance of 99 damage from 97 damage
0200400600800
100012001400160018002000
010
020
030
040
050
060
070
080
090
010
00
Distance (m)
Fre
qu
ency
distance of 00 damage from 97 damage
Two peaks1. <100m: attacking the neighbor
trees2. 300-600m: attacking trees after
middle range of dispersals
1997? 1998
1997? 1999
1997? 2000
19/22
Combination of dispersals at three Combination of dispersals at three different scales different scales ––Stratified diffusionStratified diffusion--
LongLong--distance distance dispersal (by dispersal (by winds?)(kilo meters)winds?)(kilo meters)MiddleMiddle--range range
dispersion (hundreds dispersion (hundreds meters)meters)Attack to Attack to
neighboring treesneighboring trees
20/22
Light Condition and Light Condition and Distribution of Flying Distribution of Flying AdultsAdults
Adults are positively Adults are positively phototacticphototactic..Many adults were Many adults were caught near a road.caught near a road.
Many adults were Many adults were caught around forest caught around forest gaps.gaps.0
50100150200250
? ? ? ?050
100150200250
road
UP
No. Individuals
DOWN
UP
0
40
80
120
4 8 12 16 20 24 32280
40
80
120
4 8 12 16 20 24 3228
GapUnder canopy
1
32
1
32
1
32
gap
Sticky Intercept Trap
Under canopy
Abu
ndan
ce
dark light dark light dark
road gap
21/22
TopographyTopography--SunlightSunlight--JOW IncidenceJOW Incidence
Adult flights mainly occur in the morning.Adult flights mainly occur in the morning.Adults are positively Adults are positively phototacticphototactic. . JOW occurs on eastJOW occurs on east--facing slopes that receive much facing slopes that receive much sunlight in the morning. sunlight in the morning.
0.0%
0.5%
1.0%
1.5%
N
W
S
0.0%
0.5%
1.0%
1.5%
Frequency of Incidence of JOW and slope aspects
Topography and Brightness
(Red indicates JOW incidence)
Influences of infestation history of the Influences of infestation history of the same species on reproductive success same species on reproductive success
of of Platypus Platypus quercivorusquercivorus
0
2
4
6
8 N= 396
N= 313
N= 356
N= 57
1st yr 2nd yr
Q. crispula Q. serrata
1st yr 2nd yr
b
a
*
*
A A
P. quercivorus cannot reproduce on trees that have received the attacks of the same insect species in the previous year.
No.
of n
ew a
dults
per
gal
lery
What happens in trees?What happens in trees?
1st-year gallery 2nd-year gallery
In the second year, adults of P. quercivorusavoids necrosis caused in the previous year
What happens in necrosis?What happens in necrosis?
0
100
200
300
400
500
0 20 40 min.
Abs.
Gallic acid
Ellagic acid
COOH
OHHO
OH
O
O
O
O
HO
HO OH
OH
0.05% wet weight0.05% wet weight
0.001 % wet weight0.001 % wet weight
25/22
Sapwood
Water TanninSolution
Bark
Dipping > 24hrs
Bioassay of tannins using Bioassay of tannins using P. P. quercivoraquercivora adultsadults
Water
TanninSolution
26/22
Low concentrations of GA, EA, and their mixture
High concentrations of GA, EA, and their mixture
Water
TanninSolution
Water
TanninSolution
Re-creation of an avoiding phenomena recognized in the 2nd-year gallery
27/22
P. P. quercivorusquercivorus Adults Avoids Adults Avoids Tannin Acids in SapwoodTannin Acids in Sapwood
B
B
B
B
BB
0
0.1
0.2
0.3
0.4
0.5
-5 -4 -3 -2 -1 0Concentration (% wet weight)
y=-0.1918logx-0.2573R2=0.9641p=0.0005
0.00001 0.0001 0.001 0.01 0.1 1
? ? ?B
B
B
B
BB
0
0.1
0.2
0.3
0.4
0.5
-5 -4 -3 -2 -1 0
y=-0.1918logx-0.2573R2=0.9641p=0.0005
0.00001 0.0001 0.001 0.01 0.1 1
Gallic acid
B
B
B0
0.1
0.2
0.3
0.4
0.5
-2 -1.8 -1.6 -1.4 -1.2 -1Concentration (% wet weight)
y=-1.1955logx-1.8941R2=0.9954p=0.0437
0.01 0.1
B
B
B0
0.1
0.2
0.3
0.4
0.5
-2 -1.8 -1.6 -1.4 -1.2 -1
y=-1.1955logx-1.8941R2=0.9954p=0.0437
0.01 0.1
Ellagic acid
Rat
io m
ales
pen
etra
ted
into
cub
e Gallery constructions Gallery constructions were completely were completely prevented at prevented at concentration of concentration of 0.025% of 0.025% of ellagicellagicacid and 0.05% of acid and 0.05% of gallic acid.gallic acid.
Application II:Application II:Injection of Tannin Acids to SapwoodInjection of Tannin Acids to Sapwood
30/22
Searching Chemical Attractants:Searching Chemical Attractants:Pheromones and Pheromones and KairomonesKairomones
31/22
SummarySummary
Japanese oak wilt (JOW) is an apparently Japanese oak wilt (JOW) is an apparently exotic disease complex that has caused exotic disease complex that has caused increasing levels of mass tree mortality in increasing levels of mass tree mortality in Japanese forests. Japanese forests. The disease complex consists of the The disease complex consists of the ambrosia beetle, ambrosia beetle, Platypus Platypus quercivorusquercivorus((MurayamaMurayama) and the ) and the AscomyceteAscomycete fungus fungus RaffaeleaRaffaelea quercivoraquercivora that coexist in a that coexist in a symbiotic relationship. symbiotic relationship.
32/22
SummarySummary
Warm climate since the late 1980s was the likely Warm climate since the late 1980s was the likely cause of expansion of JOW in Japan, which made cause of expansion of JOW in Japan, which made the fateful encounter of the fateful encounter of P. P. quercivorusquercivorus with with Q. Q. crispulacrispula by pushing the distribution of by pushing the distribution of P. P. quercivorusquercivorus to a more northern and higher place.to a more northern and higher place.
The incidence of JOW are more frequent on eastThe incidence of JOW are more frequent on east--facing slopes. JOW tends to occur besides gaps facing slopes. JOW tends to occur besides gaps and roads. Winds and light conditions are likely and roads. Winds and light conditions are likely factor influencing the incidence and spreads of factor influencing the incidence and spreads of JOW. JOW.
33/22
SummarySummary
Tannin acids seems useful tools to prevent Tannin acids seems useful tools to prevent P. P. quercivorusquercivorus from tunneling.from tunneling.
There are some evidences for existence of There are some evidences for existence of aggregative pheromone in aggregative pheromone in P. P. quercivorusquercivorusbut not yet detected.but not yet detected.
Recommended