Red Thread Syndrome

Question 1

Red Thread

Cause:

Answer 1

Laetisaria fuciformis

Question 2

Pink Patch and Cream Leaf Blight

Cause:

Answer 2

Liminomyces roseipellis

Question 3

Red Thread

Host:

Answer 3

Lolium, Festuca, Poa, Agrostis

Question 4

Pink Patch

Host:

Answer 4

Lolium, Festuca, Poa, Agrostis, Cynodon

Question 5

Cream Leaf Blight

Host:

Answer 5

Festuca

Question 6

Red Thread Syndrome

Symptoms:

Answer 6

• Leaf blighting - kills leaf not crown
• 1 - 5” patches of Unthrifty turf and the patches coalesce.

Question 7

Red Thread Syndrome:

Signs:

Answer 7

• Laetisaria fuciformis has cottony, hyaline (no color) to pink mycelium on leaf surface with basidium and basidiospores.
• Laetisaria forms pink, cottony flocks of arthroconidia.
• *Limonomyces *forms a pale pink mycelium.
• Limonomyces has clamp connections on Hyphae.

Question 8

Red Thread Syndrome:

Epidemiology / Predisopsitional Conditions:

Answer 8

• 32°F - 86°F (Optimum temperature- 59-77°F)
• Extended leaf wetness – heavy dew, light rain, overcast skies, fog
• Thatch accumulation (Pseudosclerotia survive in thatch)
• Drought stress
• Low height of cut
• Shredded leaf tips
• Low fertility input – K, P, Ca
• Low nitrogen input
• Use of hormonal-type pesticides

Question 9

Red Thread Syndrome:

Management Tactics

Answer 9

• Maintain a balanced fertility program
• soil test
• Maintain adequate N to inputs
  
  • _{3 - 5 lbs. per 1000 – add extra ½ to1 lb. N per100}
• ​​Use irrigation judiciously; avoid drought, but keep the foliage as dry as possible
• Mow at recommended cutting heights
• Reduce cutting height and remove clippings and pseudosclerotia during active disease
• Aerify to reduce thatch and compaction
• Use resistant varieties

Question 10

Red Thread Syndrome

Chemical Control:

Answer 10

• Tank Mix Contacts and Penetrants
  
  • Ex. Heritage and Daconil
• Get good coverage

Question 11

Laetisaria fuciformis

Answer 11

Red Thread’s scientific name:

Question 12

Describe the difference between the mycelium of Limonomyces roseipellis and Laetisaria fuciformis ?

Answer 12

Limonocyces roseipellis has Hyphae with clamp connections = doesn’t spread as easily

Laetisaria fuciformis has mycelium that form arthroconidia = spread easily.

Question 13

What is it called when you find Pink Patch on Tall Fescue?

Answer 13

Cream Leaf Blight

Question 14

Disease Cycle for Red Thread Syndrome:

Answer 14

When conditions are right, the psudosclerotia that survives in the thatch will form Hymenium that produce basidia that release basidiospores. The basidiospores spread and cling onto leaf tips and when conditions are favorable, they form red antler-like psutosclerotia. These psudosclerotia will attack the plant and can kill the grass within 2 days.