The objective of the research was to screen the biocontrol of actinomycetes able to control rice blast disease caused by Pyricularia oryzae on salt affected soils. The β-glucanase activity of the S06-MBL, S09-MBL and S17-MBL actinomycetes isolates was performed in laboratory condition with 5 replications. The result indicated that, 3 actinomyces isolates had the β-glucanolytic activity and S17-MBL isolate showed the highest β-glucanolytic activity with the β-glucan lyse halo radius of 14.0 mm and dose of β-glucanase reach 0,15 IU/ml at 14 days after testing. The biocontrol ability of 3 actinomycete isolates (S06-MBL, S09-MBL and S17-MBL) was tested with 4 replications in the nethouse condition. The results indicated that 3 isolates testing could control the disease and 2 isolates, S17-MBL and S09-MBL which were applied twice (2 days before and 2 days after pathogen inoculation) gave the highest ability to control the disease through: low ratio of disease incidence (3.48% and 2.88%); low of disease index (10.08% and 12.18%) and high efficiency of disease reduction (68.53% và 73.94%) and was not significantly compared with the chemical treatment (Beam 85) at 14 days after testing.

Keywords: Actimomycetes, β-glucanase, Pyricularia oryzae, rice blast disease