Thanjavur Wilt / Ganoderma Wilt / basal stem rot — Coconut

Symptoms

The first noticeable symptoms are yellowing, withering and drooping of the older outer-whorl leaves. The leaves gradually lose their vigour and may dry prematurely. Reddish-brown liquid may ooze through cracks or lesions near the base of the trunk. The bleeding lesions may extend upwards along the trunk. The affected bark and underlying tissues become soft and decayed around the bleeding patches. As the disease advances, the bark becomes brittle, cracks and may peel away in flakes. The internal stem tissues become discoloured, disintegrated and rotten; an unpleasant smell may be present. The basal portion of the stem progressively rots, weakening the palm. Bracket-shaped fungal fruiting bodies may appear at or near the base of the trunk. The crown may become smaller, and leaf production and nut yield decline. In severe cases, the palm undergoes progressive wilting and eventually dies.