DIAGNOSIS FOR EARLY DETECTION OF GANODERMA DISEASES IN PERENNIAL CROPS - APPROACHES AND PROSPECTS

In perennial crops like coconut, arecanut, oil palm, casuarina, Eucaly ptus, Delonix, fig, rubber and mango, Ganoderma spp., viz. G. lucidum, G. applanatum, G. boninense cause basal stem rot or wilt or root rot diseases. The pathogen is a soil-borne fungus and causes significant d amage to the crops, eventually leading to heavy loss in production in the tropical Asia. The pathogen rakes several months to express diseas e symptoms, therefore, early detection of the disease is needed to man age the disease effectively. Unfortunately currently available methods are not having any direct relationship with the Ganoderma pathogenesi s, hence alternative diagnostic methods which are highly sensitive are required. Molecular diagnostic techniques, viz. serology (both polycl onal and monoclonal antibodies), nucleic acid hybridisation and polyme rase chain reaction, and their applications and advantages over the ex isting ones are discussed.