Coconut cadang-cadang viroid (cadang cadang disease).

Abstract Cadang-cadang disease (caused by Coconut cadang-cadang viroid; CCCVd) is widely distributed in the central Philippines. It continues to spread at high rates in some provinces within the disease zone whereas other sites do not show increases in incidence. New outbreaks have been reported outside earlier boundaries of distribution. Incidence is negligible in plantations less than 10 years old, but increase is then linear at various rates up to ~1% pa. No vector has been implicated in spread so the mode of natural spread is unknown. Variants of CCCVd occur in other members of the Arecaceae including oil palm and buri palm and viroid-like sequences related to CCCVd have also been identified in a range of tropical monocotyledons in South-East Asia and Oceania. However, diagnostic facilities are poorly represented where the disease and viroid occur, and epidemiology is incompletely researched.