Diversity of endophytic fungal community of cacao (<italic>Theobroma</italic><italic> cacao</italic> L.) and biological control of <italic>Crinipellis</italic><italic> perniciosa, </italic>causal agent of Witches' Broom Disease

• Format: Article
• Language: English
• Published: Ivyspring International Publisher 2005-02-01
• Series: International Journal of Biological Sciences
• Subjects: Endophytes; antibiosis; plant resistance; biodiversity; rDNA analysis
• Online Access: http://www.biolsci.org/v01p0024.htm

<p>The basidiomycete fungus <italic>Crinipellis</italic><italic> perniciosa</italic> (Stahel) Singer is the causal agent of Witches' Broom Disease of Cacao (<italic>Theobroma</italic> <italic>cacao</italic> L.) which is the main factor limiting cacao production in the Americas. Pod losses of up to 90% are experienced in affected areas as evidenced by the 50% drop in production in Bahia province, Brazil following the arrival of the <italic>C. perniciosa</italic> in the area in 1989. The disease has proven particularly difficult to control and many farmers in affected areas have given up cacao cultivation. In order to evaluate the potential of endophytes as a biological control agent of this phytopathogen, the endophytic fungal community of resistant and susceptible cacao plants as well as affected branches was studied between 2001 and 2002. The fungal community was identified by morphological traits and rDNA sequencing as belonging to the genera <italic>Acremonium</italic>,<italic> Blastomyces</italic>, <italic>Botryosphaeria</italic>, <italic>Cladosporium</italic>, <italic>Colletotrichum</italic><italic>, Cordyceps, Diaporthe, Fusarium, Geotrichum, Gibberella, Gliocladium</italic>, <italic>Lasiodiplodia</italic><italic>, Monilochoetes</italic>, <italic>Nectria</italic><italic>, Pestalotiopsis, Phomopsis</italic>, <italic>Pleurotus</italic>, <italic>Pseudofusarium</italic><italic>, Rhizopycnis, Syncephalastrum</italic>, <italic>Trichoderma</italic>, <italic>Verticillium</italic> and<italic> Xylaria.</italic> These fungi were evaluated both <italic>in vitro</italic> and <italic>in vivo</italic> by their ability to inhibit <italic>C. perniciosa. </italic>Among these, some were identified as potential antagonists, but only one fungus (<italic>Gliocladium</italic><italic> catenulatum</italic>) reduced the incidence of Witches' Broom Disease in cacao seedlings to 70%.</p>