Efficiency of endophytic fungi isolated from healthy branches for management of vascular streak dieback on cocoa / Norliliyana Zainon

Cocoa (Theobromae cacao L.) has been known as one of the most important industrial commodities in the worldwide. However, the cocoa industry in Malaysia is significantly reduced in terms of quantity and quality of production because facing the problem of attack by pests and pathogens. In Malaysia, Vascular Streak Dieback (VSD) is one of the most significant diseases. VSD disease is caused by a fungus, Ceratobasidium theobromae, which infects the cocoa leaf during the early formation period, and then develops into an infection in the xylem vessels. In this study, endophytic fungi were used as a biological control agent and alternative method instead using chemical control that will give negative impact to human and environment. The pathogen and endophytic fungi were isolated from branches of cocoa trees and grown on potato dextrose agar (PDA), water agar and coconut agar to measure growth responds. All isolates were identified by referring to previous study by some researchers of C. Theobromae and endophytic fungi. Based on the result of the isolation, there are 6 unknown endophytic species succesfully isolated, however only 2 species can inhibit the VSD. These unknown endophytic fungi were effective to inhibit mycelial growth of C. theobromae in vitro with 62.30% inhibition. This study believed that these endophytic fungi are able to prevent growth of C. theobromae.