Chickpea Disease Management

Ken Wall PAgGrow Team Advisor (South Sask Region)Federated Co-operatives LTD

Chickpea Disease Management:• Important pulse crop in many parts of the world• Two main types – Large white seeded type (Kabuli)

Smaller dark seeded type (Desi)• Drought tolerance and an upright growth habit make chickpea suitable

for the southern prairies, even in rolling or slightly rocky sites.• Saskatchewan 2020 Seeded acreage according to Stats Canada was

about 255,000 acres, mostly Kabuli type. • Diseases are one of the most important constraints to production.

Fungal Diseases:• Seedling Blight, Root Rot, and Wilt

• Ascochyta Blight

• Sclerotina Stem Rot (White Mold)

• Botrytis Stem and Pod Rot (Grey Mold)

Diseases Caused by Bacteria and Viruses

Noninfectious Diseases:• Environmental Stress

• Herbicide Injury

Chickpea Disease Management• Ascocyta Blight• Symptoms & Life Cycle• Control: Integrated Pest Management

Seed TreatmentSeed Quality ScoutingFungicide Application/Strategies

• Biostimulants/Biologicals

Ascochyta Blight:Ascochyta rabiei (Pass.) LabrousseSexual state, Didymella rabiei (Kovachevski) Arx

• Ascochyta blight is the most serious constraint to chickpea production in Western Canada.

• It affects all above-ground plant parts, at all growth stages.• Can result in 100% yield loss• Infected seed is shriveled and discolored making it

unsuitable for many food uses.• Pathogen normally found only on chickpea, but some

isolates can infect field pea, bean, and other crop species.• Lentil pathogen is Ascochyta lentis

Symptoms:• Symptoms develop on the lower leaves as light brown lesions,

often with dark margins and spread upwards as the plants grow.• On stems, the lesions are usually darker, so the dark color of the margin

is not always prominent.• The lesions may coalesce, and quickly become dotted with small, black

fruiting bodies (pycnidia) that often develop in concentric rings.• Stems that are girdled by expanding lesions soon break, and the foliage

above the breakpoint dies.• Circular patches of dead and dying plants are highly visible in fields

where the disease is spreading quickly.• On resistant cultivars, dark brown pinprick lesions develop, but do not progress.• Lesions on the pods may lead to infection, discoloration, and shrinkage of the seed.

Control: IPMRotation - 3 to 4 year crop rotation to non-host crops is

necessary to reduce pores from previous stubble.

Field Selection - Do not plant chickpeas next to chickpea stubble.

Seeding Date - For Desi’s the recommended minimum soil temp at depth is 7oCKabuli chickpeas should be 10oC. Planting should take place as soon as soils reach these temps to give crop time to mature.

Seeding Rate - Use 1000 kernel wt to calculate optimum stand densities.3 - 3.3 established plants for Kabuli’s3.3 - 4.5 established plants for Desi’sSeeding at higher rates may increase disease severity.

Field Rolling: If rolling is necessary, it should be done prior to crop emergence.

Intercropping: Research trials with flax have shown decreased Ascochyta,reduced lodging, more consistent maturity and yield stability.

Control: Cultivars• Kabuli CP are slightly more susceptible to Ascochyta than desi CP.• Young plants are moderately resistant but resistance declines at flowering.

Variety YieldArea 1

Yield Area 2

Ascochyta Blight

Height (cm)

Days to Flower

Maturity

Kabuli

Amit (B-90) 100 100 4.4 47 56 L

CDC Alma 92 91 6.0 41 53 L

CDC Frontier 107 104 4.5 45 55 L

CDC Leader 107 105 4.5 42 54 M

CDC Luna 98 100 5.7 40 53 ML

CDC Orion 105 102 5.6 44 50 L

CDC Palmer 105 100 4.9 42 52 ML

Desi

CDC Consul 111 108 4.0 46 53 M

CDC Corey 112 106 4.3 47 56 M

Adapted fromSask Seed Guide2021

Control: Seed Treatment• Have your seed tested.• Plant only seed with ≤ 0.3% Ascochyta rabiei.• Apply fungicide seed treatments.• For a seed treatment to be effective, ensure adequate coverage

and proper rates are used.• Ensure compatability with inoculants.

Seed Treatments Registered for Control or Suppression of AscochytaVibrance Max RFC with INTEGOVibrance Maxx RTA/RFC**Trilex EverGol SHIELD*Trilex EverGol*Insure PulseCruiserMaxx Vibrance Pulses**ApronMaxx RTA with INTEGOApron Advance* Suppression only** Product contains an insecticide component

Pathogen (Disease) Threshold on Seed Action if Over Threshold

Ascochyta rabiei 0-0.3% >0.3%

Use seed treatmentDo not plant seed

Botrytis spp. 10% on seed (total of Fusarium, Botrytis & Sclerotinia)

Use seed treatment

Fusarium spp. 10% on seed (total of Fusarium, Botrytis & Sclerotinia) Soil-borne as well

Use seed treatment

Pythium spp. Not applicablesoil borne disease only

Use seed treatment if:History of disease, seeding under cool-moist conditions, planting Kabuli chickpeas.

Rhizoctonia spp. UnknownPrimarily soil borne disease

Use seed treatment if: History of disease, seeding under cool-moist conditions

Sclerotinia sclerotiorum 10% on seed (total of Fusarium, Botrytis & Sclerotinia)

Use seed treatment

General seed rot, root rot, damping off & seedling blight

Not applicable Use seed treatment if: History of disease, seeding under cool-moist conditions

Taken from SaskPulse Website – Action Thresholds and Registered Seed Treatment Options

Control: Scouting• Early identification of Ascochyta is key• Scout each field individually.• Scouting should start at the seedling stage.• Check 5-10 sites in the field in a W or large circular shape.• Pay attention to low or wet areas, heavier crop canopy,

headlands or damaged plants.• Pin flags or GPS can be used to mark areas of the field.• Take photos for a visual record.• Using a small spade, remove plants for close inspections.

Check root health as well as nodulation.• Check every 3 – 7 days during the seedling stage.• After a fungicide app, scout within 7 days to re-evaluate disease severity.• If a fungicide was not applied, scout within 3 – 5 days for a reassessment.• Scouting should be continued until the pod filling stage.

Control: Fungicide Application• Fungicides control disease by providing a protective barrier• Some fungicides have limited curative properties.• It is best to use fungicides in a preventative manner for effective

Ascochyta control.• Some fungicides have systemic properties. Able to move through the xylem

in the plant, direction of movement is upward and outward (Groups 3,7 & 11)• Some fungicides are contact only (Group M) & will not penetrate plant tissue.• Differences in level of systemic activity between active ingredients within the

same group, ie. Group 11 strobilurins.• Foliar fungicides last for about 10-14 days within the plant.

Shortened under good growing conditions or when a highly susceptible variety is grown.

Fungicides Registered for control or suppression of Ascochyta:

Fungicide Fungicide Group Max # of Apps/yr

PHI (days)

Miravis Neo 300 SE 11,7,3 1 30

Priaxor 11,7 2 30

Dyax 11,7 2 30

Delaro325 SC 11,3 2 30

Quilt/Function SC 11,3 2 30

Elatus 11,7 1 15

Lance AG 11,7 2 30

Lance WDG 7 2 21

Proline 480 SC 3 3 7

Quash* 3 2 21

Bravo 500 ZN/Echo 720 M5 3 Bravo: 14 Echo:48

Headline EC/MPower Spade 11** 2 30

* Suppression only** Must be mixed with Lance

Control: Fungicide Application• First application should be applied at the 7-10 node stage, or earliest label

staging if conditions for disease are present.• If required, a second application should be made to protect the flowers,

then make decisions on subsequent applications based on weather forecast,disease progression and crop stage.

• Coverage is critical for performance. Minimum 12 gal/acre for first application.• Higher water volumes should be used as the canopy thickens• Drier years may be able to get away with two applications, under normal or

wetter years, 4 or 5 applications may be necessary to manage Ascochyta• For further assistance regarding chickpea

fungicide application, check out the Fungicide Decision Support List-ChickpeasSask Pulse Website.

Control: Fungicide Resistance Management• Never use a strobilurin (Group 11) alone• Use tank-mixes containing multiple modes of action• Don’t cut rates• Do not apply the same group more than 2X on the same field in

one season, except for chlorothalonil which can be applied 3X• Use a strobilurin early in the season (greening effect)• Groups available for Ascochyta control are Groups 3, 7, 11 and M.• Use group M’s if a fungicide is needed for pod protection.• After the crop begins to senesce, fungicides will not be beneficial

Control: Fungicide Application Strategies

When NOT to spray• Not past the first week of August.• If disease control was ineffective and numerous lesions exist on pods.• If severe hail or other injury occurs at podding a fungicide application likely

will not protect the plant against new disease.• If estimated yield loss is less than the cost of a

fungicide don’t apply fungicide• If estimated yield loss is greater than the cost of

fungicide, apply fungicide.

Typical Chickpea Fungicide Rotations Within a Season:

Dry Year Group Wet Year GroupMiravis Neo 11,7,3 Dyax 11,7Proline 480SC 3 Delaro 325SC 11,3Bravo 500 ZN M5 Proline 480SC/Lance WDG 3/7

Bravo 500 ZN M5Bravo 500 ZN M5

Biostimulants/Biologicals:

Italpollina- Global Company based in the US

Stimtide- A product consisting of mixtures of peptides and amino acids which according to their research has been shown to among others reduce effects of abiotic stress such as weather, disease and herbicide application.

Biostimulants/Biologicals:

Questions?