ANTHRACNOSE

Causal Agent:

Colletotrichum spp. 

Susceptible Turfgrass:

Wintergrass, Bentgrass, Kentucky Bluegrasses, Fescue & Couch.

Symptoms:

• Leaves of infected plants turn yellow to a light tan to brown before dying
• Younger leaves often turn red
• Basel stem & leaf sheath's rot, affected plants are easy to pull out
• Infected areas are seen as irregular shaped patches
• Affected patches are a reddish brown colour turning yellow then tan to brown

• A black stain may occur at the base of infected plants, this is an acervulus, a black fungal fruiting body.  

Conditions Favouring Disease:

• Disease development is favoured by warm humid conditions
• Anthracnose favours temperatures over 25°C
• It is necessary for a film of moisture to be present on either the roots or foliage for infection to occur.
• More than 10 hours a day of leaf wetness for consecutive days.
• Hot summers in cool temperature areas are when the disease is most noticeable.
• Soil compaction and low amounts of nitrogen also contribute to disease occurence.

Management Tips:

• Decrease the foot traffic.
• Maintain adequate nitrogen and a balanced fertility level.
• Irrigate the turfgrass just enough to prevent wilting.
• Do not core aerate while disease symptoms are present.
• Core aerate and overseed in autumn.
• Convert to less susceptible varieties of turfgrass on fairways.
• Avoid management practices which encourage humdity and extended leaf wetness
• Make preventative fungicide applications where the disease is a chronic problem.

General comments

Anthracnose typically infects turfgrass, particulary Wintergrass during warm weather when the turfgrass canopy is wet and or humid. 

Distribution:

Found in New South Wales, Victoria, South Australia and Tasmania.
Disease is increasing, particularly in coastal NSW.

Management practices 

• Preventative fungicide program during high risk periods. 
• Decrease traffic.
• Maintain adequate nitrogen and balanced fertility.
• Do not core or aerate while disease symptoms are present.
• Avoid management practices which encourage humidity and extended leaf wetness.

Fungicidal control

Preventative applications provide optimum control of anthracnose.

The following products have label recommendation for anthracnose control in Austarlia: 

Parameter	Heritage MAXX
Mode of action	Systemic
Optimum timing	When conditions favour disease development
Dose rate	6 l/ha
Water volume	350-600 l/ha

 Refer to label for full details.

Suggested Programme

Contact Syngenta for assistance in creating a custom GreenSure Plan for your course.