btme harrogate presentation january 012
DESCRIPTION
Presentation made at BTME Harrogate on the research into phosphite mediated suppression of Microdochium nivale in turfgrassTRANSCRIPT
Suppression of
Fusarium Patch By
Phosphite in Cool
Season Amenity
Turfgrasses
John Dempsey BSc
Curragh Golf Club
and
Centre for Research in Biosciences
UWE, Bristol
Course manager of Curragh Golf Course
BSc in Turfgrass science
Myerscough college
PhD in Biosciences – Uwe, Bristol
Suppression of Microdochium nivale
Infection by Phosphite in Cool-season
Amenity Turfgrasses
CONCLUSIONS OF THE
MYERSCOUGH STUDY
Phosphite
treatment-
Not metabolised
Improved
turfgrass quality
Reduced disease
Research Objectives
Phosphite reduce
Microdochium?
Field trials
Means of reduction
Direct or indirect?
Combination?
Microdochium active on Poa annua
PHOSPHITE
Form of phosphorus
P
Phosphate PO4Phosphite PO3
Not metabolised
in plants
PHOSPHITE
Suppresses phytopathogens
Oomycete pathogens
Pythium and
Phytophthora
Anthracnose
Improved turf quality
Microdochium in cereals
No research into
Microdochium and turfgrass
Agrostis canina canina
Agrostis stolonifera
Poa annua
Trial plots
120 2 x 2 m plots
Cut at 5mm
Maintained as
greens
GRIGGS TRIALS
PK Plus 20L ha-1
PK Plus 20L ha-1
Ultraplex 10L ha-1
Chipco 20L ha-1
Chipco 20L ha-1
PK Plus 20L ha-1
NPK Control
Untreated Control
Trials running since Sept 2010
Poa annua plots
Agrostis stolonifera plots
Agrostis canina canina plots
Agrostis canina canina plots
Mean values over two years
Agrostis canina canina plots – January 2011
CONTROL PK PLUS
Poa annua plots – January 2011
CONTROL PK PLUS
Agrostis canina canina plots – January 2012
Agrostis canina canina plots – January 2012
Agrostis canina canina plots – January 2012
Poa annua plots – January 2011
Poa annua plots – January 2012
Poa annua plots – October 2011
CONTROL PK PLUS
MEANS OF SUPPRESSION
• Inhibits pathogen
Direct
• Stimulates plants defences
Indirect
Combination of both
In Vitro Study
Microdochium
propagated from
infected turfgrass
Grown on and
used for in vitro
study
To assess
inhibition of
mycelial growth
AMENDED GROWTH MEDIA
Amended PDA
Range of
phosphite and
phosphate
From 0.5 μg/ml to
1000 μg/ml
Compared with
unamended
controls
Control + 4 days
Phosphate - 100 μg/ml + 4 days
Phosphite - 100 μg/ml + 4 days
Mycelial Growth on Amended PDA
Phosphite Phosphate Control
Hyphal morphology
Unamended 75µg/ml Phosphite
Hyphal morphology
Unamended 75µg/ml Phosphite
• Measure assimilation rate
• Track translocation
• Determine accumulation amounts
• Assess the fate
Targets
•Treat turfgrass
•Collect samples
•Six week period
•Analyse - HPIC
Methods
What happens when phosphite is applied to
turfgrass?
48 hours - 4889 ppm
Further Research
Field trials
In vitro
HPIC analyses
Infection
process in
turfgrass
Defence
processes
ROS
NO2
Phytoalexin
synthesis
Measure
salicylic acid
Systemic
Acquired
Resistance
Alternative means
to suppress
Microdochium are
required
Phosphite is
rapidly
assimilated and
translocated by
turfgrass
Phosphite treated
plants less
susceptible to
Microdochium
nivale
Phosphite has a
direct inhibitory
effect on mycelial
growth
Evaluate defence
processes –
ROS, NO and
salicylic acid
Inducible defence
mechanisms
Systemic Acquired
Resistance
Summary
Updates on Twitter - @J_J_Dempsey