Ganoderma zonatum

Cladus: Eukaryota
Supergroup: Opisthokonta
Regnum: Fungi
Divisio: Basidiomycota
Classis: Basidiomycetes
Subclassis: Agaricomycetidae
Ordo: Polyporales
Familia: Ganodermataceae
Genus: Ganoderma
Species: G. zonatum

Ganoderma zonatum is a plant pathogen that infects the palm species causing butt rot. It is a fungus that infects the bottom 4 –5 feet (120 – 150 cm) of the plant also rotting the roots. It has been known to be in both natural and planted environments and in the majority of cases only in palms.

Symptoms and Diagnosis

Symptoms of Ganoderma zonatum are general decline in the health of the plant, wilting and discoloration of the leaves and slow growth. However this is noticeable in many different plant diseases and can not be used as a diagnosis tool. There are only two ways to fully identify G. zonatum. One is the bacidocarp (or conk) forming on the plant with the other viewing the internal rotting of the palm on the inside once it has been cut down.[1]
Life cycle

The fungus is spread between the plants due to the spores produced in the bacidocarp. The spores land on the soil and germinate. The hyphae then grow over the plant roots and up into the woody trunk. The fungus damages the palm trunk closest to the soil first, expands in diameter and moves up the center of the trunk causing a cone like shape of infected trunk. When the bacidocarp emerges it is at the highest point at which the fungus will internally grow.
Protection and Control

There is currently no method for the control of G. zonatum once it has been identified.[2] however minimizing the amount of moisture can decrease the risk of a palm becoming infected by the fungus. In places where a palm has previously been planted, which was infected by the fungus another should not be planted as the spores can survive in the soil. Some other prevention methods are

Avoid injury to the trunks of palm trees.
Be careful when using lawnmowers and other gardening equipment.
Consult forestry officers after infestation and seek their advice.
[1]

Mulching the wood

After fungal infection the wood above the butt area can be easily mulched, but for that extreme care should be taken to prevent the fungus from spreading. Dispose off the mulched wood by wrapping it in plastic. Use sterile tool and gloves.
External links

Index Fungorum
USDA ARS Fungal Database

References

^ Elliot, Monica; Broschat, Timothy (2000). "Ganoderma Butt Rot of Palms". University of Florida. Retrieved 2007-11-02.
^ Elliot, M. L.; Broscha, T. K. (2000). "Ganoderma Butt Rot of Palms". University of Florida. Retrieved 2007-11-02.