investigations on the spore dispersal patterns of eutypa and … · 2017-10-19 · investigations...
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The National Wine and Grape Industry Centre is a research centre within Charles Sturt University in alliance with the
Department of Primary Industry NSW and the NSW Wine Industry Australiawww.csu.edu.au/nwgic
Investigations on the spore dispersal patterns of eutypa and botryosphaeria dieback pathogens in
in Australian vineyards
R. Billones-Baaijens, S. Savocchia, M. Ayres, and M. Sosnowski
Eutypa dieback (ED) and Botryosphaeria dieback (BD)
• Ranked in top five priority diseases of Australian wine grape industry
• Ascospores and/or conidia are dispersed by rain splash and wind
• Spores infect pruning wounds leading to cankers, dieback and death
• Spore dispersal patterns in Australian vineyards unknown
• Investigate spore dispersal patterns of ED and BD
• Determine climatic conditions required for spore release
• Identify high risk infection periods in Australian vineyards
Objectives
Barossa Valley
Coonawarra
Griffith
Spore trapping(2013-2016)
Hunter Valley
Spore tapes replaced every 4-5 weeks
Burkard spore trap
Spore drum
DNA extraction from spore tapes
• DNA extracted from ½ of 2-day samples (1.9 1 cm)
• Controls – Inoculated and non-inoculated tapes
• Initially tested for presence of BD-ED by nested PCR
• Positive samples – analysed by qPCR
• Spore numbers – plotted with rainfall and maximum temperatures from each region
Diatrypaceae qPCR using multi-species primers
• Eutypa lata
• E. leptoplaca
• Cryptovalsa ampelina
• C. rabenhorstii
• Eutypella citricola
• Eu. microtheca
• Eu. cryptovalsoidea
• Diatrypella vulgaris
Photos by W. Pitt
18 S 28 S5.8 S
DIA
89RDIA 16F
DITS-1RDITS-1F
SYBR Green
125 bp
Photos by M. Sosnowski
• Diplodia seriata
• D. mutila
• Neofusicoccum parvum
• N. luteum
• N. australe
• Botryosphaeria dothidea
• Lasiodiplodia theobromae
• Spencermartinsia viticola
• Dothiorella iberica
Botryosphaeria qPCR using
multi-species primers
Photos by W. Pitt
Bot BtF1 Bot BtR1
β-tubulin nuclear gene
Bot BtF1
Bot BtR1
R QBot Btub
135 bp
Hydrolysis probe (Taqman)
Bot BtF1
0
200
400
600
800
1000
1200
0
5
10
15
20
25
30
35
40
45
50
Sep-13 Oct-13 Nov-13 Dec-13 Jan-14 Feb-14 Mar-14 Apr-14 May-14 Jun-14 Jul-14 Aug-14
No
. of
spo
res/
2-d
ay p
erio
d
Tota
l rai
nfal
l (m
m)
and
Max
Tem
pera
ture
(°C
)
Barossa Valley, SA Rain (mm) BD ED Temp (Max)
WinterAutumnSpring Summer
• 179 samples analysed, 19% positive to either ED or BD spores
• BD spores were trapped more frequently (23x) than ED spores (10x)
• ED spores, less in spring
• BD spores greater in winter and spring
96 mm
0
200
400
600
800
1000
1200
1400
1600
1800
2000
0
5
10
15
20
25
30
35
40
45
Dec-14 Jan-15 Feb-15 Mar-15 Apr-15 May-15 Jun-15 Jul-15 Aug-15 Sep-15 Oct-15 Nov-15
No.
of s
pore
s/2-
day
perio
d
Tota
l Rai
nfa
ll (m
m)
and
Max
Tem
per
atu
re (
°C)
Coonawarra, SA Rain (mm) ED BD Temp (Max)
SpringWinterAutumnSummer
54002010
• 172 samples analysed, 33% positive to either ED or BD spores
• BD spores and ED spores – trapped similar frequency
• ED spores – up to 5400 spores, greater in winter (54%)
• BD spores greater in winter (48%)
0
200
400
600
800
1,000
1,200
1,400
0
5
10
15
20
25
30
35
40
45
Jun-14 Jul-14 Aug-14 Sep-14 Oct-14 Nov-14 Dec-14 Jan-15 Feb-15 Mar-15 Apr-15 May-15
No. o
f sp
ore
s/2
-da
y p
erio
d
To
tal ra
infa
ll (m
m)
an
d M
ax T
em
pe
ratu
re (°C
)
Griffith, NSW Rain BD ED Temp (Max)
SpringWinter AutumnSummer
2730
• 182 samples analysed, 36% positive to either ED or BD spores
• BD spores and ED spores –similar frequency
• ED spore release – similar across 4 seasons
• BD spores greater in summer (54%), only 14% in winter
0
250
500
750
1000
1250
1500
1750
2000
2250
2500
0
5
10
15
20
25
30
35
40
45
Jun-14 Jul-14 Aug-14 Sep-14 Oct-14 Nov-14 Dec-14 Jan-15 Feb-15 Mar-15 Apr-15 May-15
No.
of spore
s/2
-day p
eriod
Tota
l ra
infa
ll (m
m)
and
Max T
em
pera
ture
(°C
)
Hunter Valley, NSW Rain BD ED Temp (max)
SpringWinter AutumnSummer
• 195 samples analysed, 39% positive to either ED or BD spores
• ED spores more frequent (21%) than BD (18%) - Eutypella microtheca, not Eutypa lata.
• ED spores – less in winter (19%), compared to other seasons (27%)
• BD spores greater in autumn (34%)
4980 spores7500 spores
211 mm
Summary of results
• ED and BD spores released sporadically and occasionally both detected in same period/sample
• Seasonal release and no. of spores differed between regions and pathogens SA - higher spores in winter NSW - higher spores in summer Differences in regions - mainly attributed to rainfall
• Rainfall - primary factor in spore release 0.2 mm rain resulted in spore release Not all rain events resulted in spore release Few occasions, spores released a week after rainfall
– dew or relative humidity also a factor?
Differences between pathogens
• ED spores - up to 7,500 spores in a 2-day sample
• BD spores – up to 1,300 in a 2-day sample, mostly only up to 300
spores
• Differences - due to the size and mode of discharge
• ED pathogens - actively eject their ascospores – travel long distances
• BD spores - released in slimy masses – less airborne, more rain-
splashed
• ED ascospores are smaller than BD spores – lighter for wind dispersal
Photos: F. Trouillas, W. Pitt
Collaborators:
Jose Urbez-Torres (SuRDC)
Eileen Scott (Uni of Adelaide)
Chris Steel, Gavin Ash (NWGIC)
Trevor Wicks (ex. SARDI)
RESEARCH TEAM
SARDI Plant Research Centre
University of Adelaide
NWGIC
Regina Billones
Baaijens
Sandra Savocchia
(NWGIC)
Matthew Ayres,
Mark Sosnowski
(SARDI)
Practical Management of Grapevine Trunk Diseases(2013-2016)
Clare Region WGGA
Acknowledgements