Oral Presentation 37 by Weidong Chen at the International Conference on Pulses in Marrakesh, Morocco, 18-20 April 2016

1. Management
of
Soilborne
Diseases
for
Sustainable
Pulse
Crop
Produc8on
Weidong
Chen
USDA
ARS,
Washington
State
University
Pullman,
WA
99164,
USA
Interna8onal
Conference
on
Pulses
Marrakesh,
Morocco
April
18-­‐20,
2016

2. Soilborne
Diseases
versus
Foliar
Diseases
Foliar
diseases
are
usually
favored
by
lush
vegeta8ve
growth.
Soilborne
diseases
are
usually
exacerbated
by
poor
vegeta8ve
growth.

3. Unique
Features
of
Soilborne
Diseases
• Reside
in
an
opaque
matrix
• Complex
habitat:
Physical,
chemical
and
biological
components
• Fungicide
applica8ons
usually
ineffec8ve
or
uneconomical
• Management
prac8ces
well
planned
and
executed
ahead
of
plan8ng

4. Soilborne
Diseases
Cool
weather
diseases
Pythium
and
Rhizoctonia
damping-­‐off
Aphanomyces
root
rot
Warm
weather
diseases
Fusarium
wilt
Fusarium
root
rot
Sclero8um
collar
rot
Charchoal
rot

5. Fusarium
wilts
• Pea
-­‐
Fusarium
oxysporium
f.
sp.
pisi
– Races
1,
2,
5
and
6
• Chickpea
-­‐
Fusarium
oxysporium
f.
sp.
ciceri
– Races
0,
1A,
1B/C,
2,
3,
4,
5
and
6
• Len8l
-­‐
Fusarium
oxysporium
f.
sp.
len1s
• Dispersal:
by
means
of
movement
of
soil,
plant
fragments
by
water,
wind,
and
people

6. Vascular
discolora8on

7. Fusarium
wilt

8. Chickpea
differen8als
for
races
of
Fusarium
wilt

9. In
many
parts
of
the
world,
Fusarium
wilt
could
be
confounded
with
root
rot
caused
by
Fusraium
redolens.

10. Fusarium
root
rot
• Caused
by
Fusarium
redolens,
and
F.
solani
• Occurs
on
pulse
crops
throughout
the
world
• Occurs
usually
on
stressed
plants,
o6en
in
hot,
dry
season.
• Ini:ally
reddish
brown
discolora:on
of
roots,
then
turn
darker
as
disease
progress
• Above
ground
symptoms
include
stunted
growth,
yellowing
and
necrosis
of
basal
foliage

12. Fusarium
Black
Root
Rot
of
Len8l

13. Rhizoctonia
root
rot

14. Pythium
damping-­‐off
caused
by
metalaxyl-­‐resistant
Pythium
spp.

16. No Metalaxyl
With Metalaxyl
Resistant
Sensitive

17. New
fungicide
Intego
effec8ve
against
metalaxyl-­‐resistant
Pythium

18. Long-­‐term
Sustainable
approaches
to
managing
soilborne
diseases
• Use
resistant
cul8vars
whenever
possible.
• Rotate
with
non-­‐legume
(non-­‐host)
crops.
• Reduced
and
conserva8ve
8llage.
• Increase
organic
maer,
microbial
biomass,
ac8vity
and
diversity
• Improve
soil
health
(the
capacity
to
func8on
as
a
vital
living
system
to
sustain
biological
produc8vity,
promote
plant
health).