Page 150 Page 154 Page 158 GREEN BEANS AND PEAS
Transcript Of Page 150 Page 154 Page 158 GREEN BEANS AND PEAS
GREEN BEANS AND PEAS
Aphanomyces root rot
Page 134
Ashy stem blight (charcoal rot)
Page 138
Black root rot Page 142
Black spot Page 146
Fusarium root rot
Page 150
Pea wilt Page 154
Pythium stem rot
Page 158
Rhizoctonia root rot
Page 162
Sclerotinia rot (white mould)
Page 166
Sclerotium rot Page 170
132 SOIL-BORNE DISEASES IN VEGETABLE CROPS
SOIL-BORNE DISEASES IN VEGETABLE CROPS 133
GREEN BEANS AND PEAS
APHANOMYCES ROOT ROT
Aphanomyces euteiches
WHAT SHOULD I LOOK FOR?
GREEN BEANS AND PEAS | APHANOMYCES ROOT ROT
Initial honey-brown discolouration of root and area above the seed up to the soil line as shown in plants on right hand side, compared to healthy plants on the left. Nodulation on roots may also be poor. Roots become darker as disease progresses and eventually die
L. Porter, ARS USDA
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
ROOTS
STEM
134 SOIL-BORNE DISEASES IN VEGETABLE CROPS
WARM
WET
• 22-28ºC
Aboveground yellowing will occur starting at the bottom leaves, followed by wilting and death
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
WIND
FREE WATER
MOVEMENT OF CONTAMINATED
SOIL
CONTAMINATED PLANT DEBRIS
SURVIVAL TIME WITHOUT HOST
Mo
SOIL-BORNE DISEASES IN VEGETABLE CROPS 135
FALLOW/COVER CROP
HOW DO I CONTROL IT?
FARM HYGIENE
Stop movement of contaminated soil, water, plants and equipment
STOP
CROP ROTATION
Select non-host rotation or cover
crops
HOST-FREE ZONE
Control volunteer host plants and weeds
• 6 to 10 year rotation
SOIL TEST
Conduct a pre-sowing soil test to help predict
level of risk
NO RESIDUE AT
PLANTING
Ensure no plant residues from host crops at planting
DRAINAGE
Plant on raised beds or
well-draining soil
PLANTING PREPARATION
POST-PLANT
IRRIGATION
MANAGEMENT
Monitor crop and soil to optimize
amount and timing
CONTROL PESTS
Control insect pests that
spread spores
• Sciarid flies can spread spores and larvae damage roots
HOST RANGE
Range of legume crops and weed species including peas, beans, clovers and medics
136 SOIL-BORNE DISEASES IN VEGETABLE CROPS
BIO FUMIGATION
Grow a biofumigant crop
CHEMICAL FUMIGATION
Always use with care and as per
label
IMPROVE SOIL HEALTH
Add organic matter or amendments to
boost beneficial microbes
• Consult APVMA or InfoPest website for current registered products
CROP SELECTION
Choose a resistant/less susceptible cultivar
• Avoid late-maturing varieties especially in paddocks with history of Aphanomyces root rot
SOIL-BORNE DISEASES IN VEGETABLE CROPS 137
GREEN BEANS AND PEAS | APHANOMYCES ROOT ROT
GREEN BEANS AND PEAS
ASHY STEM BLIGHT (CHARCOAL ROT)
Macrophomina phaseolina
WHAT SHOULD I LOOK FOR?
GREEN BEANS AND PEAS | ASHY STEM BLIGHT (CHARCOAL ROT)
Sunken lesions develop on the stem, as shown here in seedlings. Lesions have sharp
margins and may contain concentric rings
H. Schwartz, Colorado State University, Bugwood.org
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
STEM
WARM
DRY
• 24-27ºC
138 SOIL-BORNE DISEASES IN VEGETABLE CROPS
As the disease progresses, dry rot of the stem and pale, ash-coloured “dust” develop
H. Schwartz, Colorado State University, Bugwood.org
Small black survival structures (microsclerotia) develop in dead tissue
P. Bachi, University of Kentucky Research and Education Center, Bugwood.org
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
FREE WATER
MOVEMENT OF CONTAMINATED
SOIL
SURVIVAL TIME WITHOUT HOST
Mo
SOIL-BORNE DISEASES IN VEGETABLE CROPS 139
FALLOW/COVER CROP
HOW DO I CONTROL IT?
FARM HYGIENE
Stop movement of contaminated soil, water, plants and equipment
STOP
CROP SELECTION
Choose a resistant/less susceptible cultivar
CROP ROTATION
Select non-host rotation or cover
crops
• 4 to 6 year break from susceptible crop
USE CLEAN SEED OR
SEEDLINGS
Source seed/ seedlings from a certified reputable
source
IMPROVE SOIL HEALTH
Add organic matter or amendments to
boost beneficial microbes
NO RESIDUE AT
PLANTING
Ensure no plant residues from host crops at planting
PLANTING PREPARATION
POST-PLANT
AVOID WATER STRESS
Ensure plants receive adequate
water
GOOD NUTRITION
Ensure plants’ nutritional needs
are met
AVOID PLANT INJURY
Avoid any physical damage to plant
• Avoid excess Nitrogen
HOST RANGE
Very wide, host range infecting over 500 plant species including members of the pumpkin, bean, brassica and pepper families. 140 SOIL-BORNE DISEASES IN VEGETABLE CROPS
SOIL SOLARISATION
Cover soil with a tarp and kill
harmful pathogens
BIO FUMIGATION
Grow a biofumigant crop
SOIL TEST
Conduct a pre-sowing soil test to help predict
level of risk
CHEMICAL TREATMENT
Treat seed/ seedlings with registered fungicide
• Consult APVMA or InfoPest website for current registered products
SOIL-BORNE DISEASES IN VEGETABLE CROPS 141
GREEN BEANS AND PEAS | ASHY STEM BLIGHT (CHARCOAL ROT)
GREEN BEANS AND PEAS
BLACK ROOT ROT
Thielaviopsis basicola (aka. Chalara elegans)
WHAT SHOULD I LOOK FOR?
GREEN BEANS AND PEAS | BLACK ROOT ROT
Initially long red lesions appear on the root which eventually turn black
Virginia Tech Learning Resources Center
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
ROOTS
142 SOIL-BORNE DISEASES IN VEGETABLE CROPS
WARM
WET
• 17-25ºC
Tap root may become stunted, aboveground plant may also become stunted, wilt and
possibly die
N. Cattlin, Alamy Stock Photo
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
MOVEMENT OF CONTAMINATED
SOIL
CONTAMINATED PLANT DEBRIS
SURVIVAL TIME WITHOUT HOST
Mo
SOIL-BORNE DISEASES IN VEGETABLE CROPS 143
FALLOW/COVER CROP
HOW DO I CONTROL IT?
FARM HYGIENE
Stop movement of contaminated soil, water, plants and equipment
STOP
NO RESIDUE AT
PLANTING
Ensure no plant residues from host crops at planting
CROP ROTATION
Select non-host rotation or cover
crops
IMPROVE SOIL HEALTH
Add organic matter or amendments to
boost beneficial microbes
• 5 to 6 year break from host crops
DRAINAGE
Plant on raised beds or
well-draining soil
BIO FUMIGATION
Grow a biofumigant crop
PLANTING PREPARATION
POST-PLANT
IRRIGATION
MANAGEMENT
Monitor crop and soil to optimize
amount and timing
AVOID PLANT INJURY
Avoid any physical damage to plant
• Minimise irrigation splash
HOST RANGE
Wide host range, including beans, peas, cotton, lettuces, lucerne, lupin and soybean
144 SOIL-BORNE DISEASES IN VEGETABLE CROPS
SOIL-BORNE DISEASES IN VEGETABLE CROPS 145
GREEN BEANS AND PEAS | BLACK ROOT ROT
GREEN BEANS AND PEAS
BLACK SPOT (ASCOCHYTA BLIGHT)
Didymella pinodes often in a disease complex with Phoma medicaginis var. pinodella,
WHAT SHOULD I LOOK FOR?
Phoma Koolunga and Didymella pisi.
GREEN BEANS AND PEAS | FAMILYBLACK SPOT (ASCOCHYTA BLIGHT)
Irregular dark brown to black spots that develop into large purplish-black lesions on stems,
leaves and pods.
M. Wunsch, North Dakota State University
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
WHOLE PLANT
ROOTS
• In severe cases
146 SOIL-BORNE DISEASES IN VEGETABLE CROPS
WARM
• 18-22ºC
WET
Concentric rings and black survival structures (pycnidia) can often be seen in the middle of
the lesion.
M. Wunsch, North Dakota State University
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
INFECTED SEED/ SEEDLINGS
MOVEMENT OF CONTAMINATED
SOIL
CONTAMINATED PLANT DEBRIS
SURVIVAL TIME WITHOUT HOST
< 33-y1e0arysears
SOIL-BORNE DISEASES IN VEGETABLE CROPS 147
GREEN BEANS AND PEAS | FAMILYBLACK SPOT (ASCOCHYTA BLIGHT)
HOW DO I CONTROL IT?
FALLOW/COVER CROP
FARM HYGIENE
Stop movement of contaminated soil, water, plants and equipment
STOP
HOST-FREE ZONE
Control volunteer host plants and weeds
CROP ROTATION
Select non-host rotation or cover
crops
• Minimum 3 year break and 500m from previous host crops
PLANTING PREPARATION
NO RESIDUE AT
PLANTING
Ensure no plant residues from host crops at planting
USE CLEAN SEED OR
SEEDLINGS
Source seed/ seedlings from a certified reputable
source
ADJUST DATE
Adjust planting/harvest date to reduce
infection risk
• Avoid early planting at high seeding rates which increases exposure
HOST RANGE Most severe on peas, but also infects lentils, alfalfa, faba beans, clover and vetch
148 SOIL-BORNE DISEASES IN VEGETABLE CROPS
AIR CIRCULATION
Increase row/plant spacing to improve
air flow
CHEMICAL TREATMENT
Treat seed/ seedlings with registered fungicide
• Consult APVMA or InfoPest website for current registered products
SOIL-BORNE DISEASES IN VEGETABLE CROPS 149
GREEN BEANS AND PEAS
FUSARIUM ROOT ROT
Fusarium solani f. sp. phaseoli
WHAT SHOULD I LOOK FOR?
GREEN BEANS AND PEAS | FUSARIUM ROOT ROT
Aboveground plants may initially appear yellow, stunted and wilted and eventually may die
H. Schwartz, Colorado State University, Bugwood.org
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
ROOTS
150 SOIL-BORNE DISEASES IN VEGETABLE CROPS
COOL
• Soil <13oC at planting
COMPACTED SOIL
Belowground lower root may die off and secondary roots may form above the diseased area
H. Schwartz, Colorado State University, Bugwood.org
Cutting the stem reveals drying out and reddening of the taproot
H. Schwartz, Colorado State University, Bugwood.org
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
CONTAMINATED PLANT DEBRIS
INFECTED SEED/ SEEDLINGS
MOVEMENT OF CONTAMINATED
SOIL
INSECTS
SURVIVAL TIME WITHOUT HOST
Mo
SOIL-BORNE DISEASES IN VEGETABLE CROPS 151
Aphanomyces root rot
Page 134
Ashy stem blight (charcoal rot)
Page 138
Black root rot Page 142
Black spot Page 146
Fusarium root rot
Page 150
Pea wilt Page 154
Pythium stem rot
Page 158
Rhizoctonia root rot
Page 162
Sclerotinia rot (white mould)
Page 166
Sclerotium rot Page 170
132 SOIL-BORNE DISEASES IN VEGETABLE CROPS
SOIL-BORNE DISEASES IN VEGETABLE CROPS 133
GREEN BEANS AND PEAS
APHANOMYCES ROOT ROT
Aphanomyces euteiches
WHAT SHOULD I LOOK FOR?
GREEN BEANS AND PEAS | APHANOMYCES ROOT ROT
Initial honey-brown discolouration of root and area above the seed up to the soil line as shown in plants on right hand side, compared to healthy plants on the left. Nodulation on roots may also be poor. Roots become darker as disease progresses and eventually die
L. Porter, ARS USDA
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
ROOTS
STEM
134 SOIL-BORNE DISEASES IN VEGETABLE CROPS
WARM
WET
• 22-28ºC
Aboveground yellowing will occur starting at the bottom leaves, followed by wilting and death
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
WIND
FREE WATER
MOVEMENT OF CONTAMINATED
SOIL
CONTAMINATED PLANT DEBRIS
SURVIVAL TIME WITHOUT HOST
Mo
SOIL-BORNE DISEASES IN VEGETABLE CROPS 135
FALLOW/COVER CROP
HOW DO I CONTROL IT?
FARM HYGIENE
Stop movement of contaminated soil, water, plants and equipment
STOP
CROP ROTATION
Select non-host rotation or cover
crops
HOST-FREE ZONE
Control volunteer host plants and weeds
• 6 to 10 year rotation
SOIL TEST
Conduct a pre-sowing soil test to help predict
level of risk
NO RESIDUE AT
PLANTING
Ensure no plant residues from host crops at planting
DRAINAGE
Plant on raised beds or
well-draining soil
PLANTING PREPARATION
POST-PLANT
IRRIGATION
MANAGEMENT
Monitor crop and soil to optimize
amount and timing
CONTROL PESTS
Control insect pests that
spread spores
• Sciarid flies can spread spores and larvae damage roots
HOST RANGE
Range of legume crops and weed species including peas, beans, clovers and medics
136 SOIL-BORNE DISEASES IN VEGETABLE CROPS
BIO FUMIGATION
Grow a biofumigant crop
CHEMICAL FUMIGATION
Always use with care and as per
label
IMPROVE SOIL HEALTH
Add organic matter or amendments to
boost beneficial microbes
• Consult APVMA or InfoPest website for current registered products
CROP SELECTION
Choose a resistant/less susceptible cultivar
• Avoid late-maturing varieties especially in paddocks with history of Aphanomyces root rot
SOIL-BORNE DISEASES IN VEGETABLE CROPS 137
GREEN BEANS AND PEAS | APHANOMYCES ROOT ROT
GREEN BEANS AND PEAS
ASHY STEM BLIGHT (CHARCOAL ROT)
Macrophomina phaseolina
WHAT SHOULD I LOOK FOR?
GREEN BEANS AND PEAS | ASHY STEM BLIGHT (CHARCOAL ROT)
Sunken lesions develop on the stem, as shown here in seedlings. Lesions have sharp
margins and may contain concentric rings
H. Schwartz, Colorado State University, Bugwood.org
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
STEM
WARM
DRY
• 24-27ºC
138 SOIL-BORNE DISEASES IN VEGETABLE CROPS
As the disease progresses, dry rot of the stem and pale, ash-coloured “dust” develop
H. Schwartz, Colorado State University, Bugwood.org
Small black survival structures (microsclerotia) develop in dead tissue
P. Bachi, University of Kentucky Research and Education Center, Bugwood.org
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
FREE WATER
MOVEMENT OF CONTAMINATED
SOIL
SURVIVAL TIME WITHOUT HOST
Mo
SOIL-BORNE DISEASES IN VEGETABLE CROPS 139
FALLOW/COVER CROP
HOW DO I CONTROL IT?
FARM HYGIENE
Stop movement of contaminated soil, water, plants and equipment
STOP
CROP SELECTION
Choose a resistant/less susceptible cultivar
CROP ROTATION
Select non-host rotation or cover
crops
• 4 to 6 year break from susceptible crop
USE CLEAN SEED OR
SEEDLINGS
Source seed/ seedlings from a certified reputable
source
IMPROVE SOIL HEALTH
Add organic matter or amendments to
boost beneficial microbes
NO RESIDUE AT
PLANTING
Ensure no plant residues from host crops at planting
PLANTING PREPARATION
POST-PLANT
AVOID WATER STRESS
Ensure plants receive adequate
water
GOOD NUTRITION
Ensure plants’ nutritional needs
are met
AVOID PLANT INJURY
Avoid any physical damage to plant
• Avoid excess Nitrogen
HOST RANGE
Very wide, host range infecting over 500 plant species including members of the pumpkin, bean, brassica and pepper families. 140 SOIL-BORNE DISEASES IN VEGETABLE CROPS
SOIL SOLARISATION
Cover soil with a tarp and kill
harmful pathogens
BIO FUMIGATION
Grow a biofumigant crop
SOIL TEST
Conduct a pre-sowing soil test to help predict
level of risk
CHEMICAL TREATMENT
Treat seed/ seedlings with registered fungicide
• Consult APVMA or InfoPest website for current registered products
SOIL-BORNE DISEASES IN VEGETABLE CROPS 141
GREEN BEANS AND PEAS | ASHY STEM BLIGHT (CHARCOAL ROT)
GREEN BEANS AND PEAS
BLACK ROOT ROT
Thielaviopsis basicola (aka. Chalara elegans)
WHAT SHOULD I LOOK FOR?
GREEN BEANS AND PEAS | BLACK ROOT ROT
Initially long red lesions appear on the root which eventually turn black
Virginia Tech Learning Resources Center
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
ROOTS
142 SOIL-BORNE DISEASES IN VEGETABLE CROPS
WARM
WET
• 17-25ºC
Tap root may become stunted, aboveground plant may also become stunted, wilt and
possibly die
N. Cattlin, Alamy Stock Photo
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
MOVEMENT OF CONTAMINATED
SOIL
CONTAMINATED PLANT DEBRIS
SURVIVAL TIME WITHOUT HOST
Mo
SOIL-BORNE DISEASES IN VEGETABLE CROPS 143
FALLOW/COVER CROP
HOW DO I CONTROL IT?
FARM HYGIENE
Stop movement of contaminated soil, water, plants and equipment
STOP
NO RESIDUE AT
PLANTING
Ensure no plant residues from host crops at planting
CROP ROTATION
Select non-host rotation or cover
crops
IMPROVE SOIL HEALTH
Add organic matter or amendments to
boost beneficial microbes
• 5 to 6 year break from host crops
DRAINAGE
Plant on raised beds or
well-draining soil
BIO FUMIGATION
Grow a biofumigant crop
PLANTING PREPARATION
POST-PLANT
IRRIGATION
MANAGEMENT
Monitor crop and soil to optimize
amount and timing
AVOID PLANT INJURY
Avoid any physical damage to plant
• Minimise irrigation splash
HOST RANGE
Wide host range, including beans, peas, cotton, lettuces, lucerne, lupin and soybean
144 SOIL-BORNE DISEASES IN VEGETABLE CROPS
SOIL-BORNE DISEASES IN VEGETABLE CROPS 145
GREEN BEANS AND PEAS | BLACK ROOT ROT
GREEN BEANS AND PEAS
BLACK SPOT (ASCOCHYTA BLIGHT)
Didymella pinodes often in a disease complex with Phoma medicaginis var. pinodella,
WHAT SHOULD I LOOK FOR?
Phoma Koolunga and Didymella pisi.
GREEN BEANS AND PEAS | FAMILYBLACK SPOT (ASCOCHYTA BLIGHT)
Irregular dark brown to black spots that develop into large purplish-black lesions on stems,
leaves and pods.
M. Wunsch, North Dakota State University
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
WHOLE PLANT
ROOTS
• In severe cases
146 SOIL-BORNE DISEASES IN VEGETABLE CROPS
WARM
• 18-22ºC
WET
Concentric rings and black survival structures (pycnidia) can often be seen in the middle of
the lesion.
M. Wunsch, North Dakota State University
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
INFECTED SEED/ SEEDLINGS
MOVEMENT OF CONTAMINATED
SOIL
CONTAMINATED PLANT DEBRIS
SURVIVAL TIME WITHOUT HOST
< 33-y1e0arysears
SOIL-BORNE DISEASES IN VEGETABLE CROPS 147
GREEN BEANS AND PEAS | FAMILYBLACK SPOT (ASCOCHYTA BLIGHT)
HOW DO I CONTROL IT?
FALLOW/COVER CROP
FARM HYGIENE
Stop movement of contaminated soil, water, plants and equipment
STOP
HOST-FREE ZONE
Control volunteer host plants and weeds
CROP ROTATION
Select non-host rotation or cover
crops
• Minimum 3 year break and 500m from previous host crops
PLANTING PREPARATION
NO RESIDUE AT
PLANTING
Ensure no plant residues from host crops at planting
USE CLEAN SEED OR
SEEDLINGS
Source seed/ seedlings from a certified reputable
source
ADJUST DATE
Adjust planting/harvest date to reduce
infection risk
• Avoid early planting at high seeding rates which increases exposure
HOST RANGE Most severe on peas, but also infects lentils, alfalfa, faba beans, clover and vetch
148 SOIL-BORNE DISEASES IN VEGETABLE CROPS
AIR CIRCULATION
Increase row/plant spacing to improve
air flow
CHEMICAL TREATMENT
Treat seed/ seedlings with registered fungicide
• Consult APVMA or InfoPest website for current registered products
SOIL-BORNE DISEASES IN VEGETABLE CROPS 149
GREEN BEANS AND PEAS
FUSARIUM ROOT ROT
Fusarium solani f. sp. phaseoli
WHAT SHOULD I LOOK FOR?
GREEN BEANS AND PEAS | FUSARIUM ROOT ROT
Aboveground plants may initially appear yellow, stunted and wilted and eventually may die
H. Schwartz, Colorado State University, Bugwood.org
WHERE WILL I SEE SYMPTOMS?
FAVOURABLE CONDITIONS FOR DISEASE DEVELOPMENT
ROOTS
150 SOIL-BORNE DISEASES IN VEGETABLE CROPS
COOL
• Soil <13oC at planting
COMPACTED SOIL
Belowground lower root may die off and secondary roots may form above the diseased area
H. Schwartz, Colorado State University, Bugwood.org
Cutting the stem reveals drying out and reddening of the taproot
H. Schwartz, Colorado State University, Bugwood.org
DISTRIBUTION IN THE FIELD
SCATTERED Individual/small patches of
infected plants
HOW DOES IT SPREAD?
CONTAMINATED PLANT DEBRIS
INFECTED SEED/ SEEDLINGS
MOVEMENT OF CONTAMINATED
SOIL
INSECTS
SURVIVAL TIME WITHOUT HOST
Mo
SOIL-BORNE DISEASES IN VEGETABLE CROPS 151