May 2013 Pest of the Month

Gliocladium blight – Pink Rot of Palms

  • Pathogen:  Gliocladium vermoeseni (fungus) (recently renamed Nalanthamala vermoeseni).
  • Hosts: Chamaedorea spp, Dypsis spp. (Areca palms, etc.), date palm, queen palm, Mexican fan palm, others.
  • Symptoms: Invasive rot of buds, petioles, leaf blades, and trunks/stems, dark brown necrotic areas near the base of the stem, gummy exudates, premature death of fronds, plant death.
  • Signs: Pink- to salmon-colored spore masses on the surface of diseased plants.
  • IPM: Minimize plant wounding, use of fungicides as prophylactic during transplanting, minimize water splashing between plants, remove dead leaves from plants, use increased plant spacing, provide air movement, decrease relative humidity, irrigate in the morning to avoid prolonged periods of wetness.
  • Fungicides: Dithane, Thiophanate methyl. Apply after removing diseased leaves.

 

Source for photos: https://www.icloud.com/iphoto/projects/#7;CAEQARoQr81AB2fnB2ELWhcKQh0hsg;DBA775CB-0656-4F1C-98B1-661C17D5D646

Reference: http://www.ctahr.hawaii.edu/nelsons/palms/Gliocladium.htm
http://itp.lucidcentral.org/id/palms/symptoms/Gliocladium_Blight_and_Gliocladium_Trunk_Rot.htm