Penicillium citrinum as a Potential Biocontrol Agent for Sisal Bole Rot Disease

Agave sisalana, known as sisal, yields the world’s main natural stiff fiber used to produce various industrial products. The Brazilian semiarid is the largest sisal producing region in the world; however, production is under threat by sisal bole rot disease, caused by Aspergillus welwitschiae. Since chemical control of this disease is questionable in drought-ridden areas with little investment in crop management and due to environmental and public health concerns, the search for a biocontrol agent against A. welwitschiae is warranted. In this work, we isolated and identificated Penicillium citrinum as an endophyte from sisal plants collected from the Brazilian semi-arid and investigated whether it could be a biocontrol agent against sisal bole rot. P. citrinum inhibited the mycelium growth of A. welwitschiae by 65.8% when inoculated 72 hours before the pathogen, in dual culture medium assays. We found that P. citrinum can reduce sisal bole rot disease up to 90% when inoculated in sisal plants 48 hours before pathogen inoculation. Altogether, our data suggest a potential role for P. citrinum in the control of sisal bole rot disease.