First report of vascular streak dieback symptom of cocoa caused by Ceratobasidium theobromae in Barru District, South Sulawesi

Abstract

The cause of vascular streak dieback disease, Ceratobasidium theobromae is an economic important cocoa pathogen wherever it attacks and therefore its spread poses a high attention to develop cocoa industry. One of National Islands facing the disease constraint is Sulawesi that many cocoa areas are infected by the pathogen. Understanding a source of pathogen infection in the cocoa farm by investigating specific signs of green chlorotic lesion followed by necrotic leaf and brown streaking within vascular layer is a common method. However, this method is not fully correct since the co-infection phenomenon, secondary fungal pathogens associated with the symptom, has occurred in the field and therefore, the need for detecting accurately by a molecular approach is a highly recommended. This paper will reveal the presence of VSD symptom and pathogen in the new cocoa areas, Barru district before suggestion way of limiting pathogen distribution to new areas was undertaken. Testing the presence of VSD disease pathogen was confirmed with PCR analysis using a pair of specific primers for C. theobromae; Than_ITS1 (forward) and Than_ITS2 (revers). The finding suggests that the signs of VSD disease symptom and pathogen were found to spread in nine villages in Barru district.