Actinobacteria in the control of leaf disease in rubber tree seedlings

Abstract

The rubber tree (Hevea spp.), Native to the Amazon region, is the largest source of natural
rubber. However, one of the main phytosanitary problems that affects this crop, is the evil of
the leaves, caused by the fungus Pseudocercospora ulei. Actinobacteria are microorganisms
that present great potential as biocontrol agents of plant diseases, due to the production of antibiotics
and enzymes that act to inhibit pathogens. The objective of this work was to evaluate
the efficiency of actinobacteria isolates in the control of leaf disease in rubber tree seedlings.
The metabolites of the actinobacteria isolates reduced the germination of spores by up to
43.4% and the mycelial growth of the fungus P. ulei by 77.1%. All isolates when applied via leaf
spraying reduced the severity of the disease in rubber tree seedlings compared to control. Isolates
of actinobacteria showed potential in the control of leaf disease in rubber tree seedlings.