Five Bacillus strains were screened against Phytophthora palmivora MNP13, which causes durian root and stem rot. B. subtilis TU089 inhibited growth by 76.56±0.23% on plates and was developed into an encapsulated product at about 10^8 CFU/mL that retained activity comparable to fresh cells. Cell assays yielded IC10 values of 1,090 µg/mL in MRC-5 and 309.82 µg/mL in HaCaT cells; acute oral testing found no significant adverse effects under the studied conditions. Efficacy remains laboratory-based and safety preliminary.
Key findings
- B. subtilis TU089 produced the highest dual-culture inhibition at 76.56±0.23%.
- The encapsulated product contained about 10^8 CFU/mL and retained activity comparable with fresh TU089 cells, although the abstract reports no comparison statistic.
- IC10 values were 1,090 µg/mL in MRC-5 and 309.82 µg/mL in HaCaT cells; acute testing found no significant adverse effects under the experimental conditions.
Why this matters globally
Durian root and stem rot threatens production and exports. A microbial product could reduce chemical dependence within integrated disease management if stability, orchard efficacy, non-target effects and cost-effectiveness are demonstrated.
Thai researcher contribution
Thammasat University researchers carried the work from strain screening through formulation and preliminary safety assessment for a major Thai durian disease.
Limitations to consider
Antagonism was chiefly in vitro against MNP13, with no greenhouse or orchard efficacy. Shelf life, persistence and non-target effects were not reported, and the abstract omits acute-test animal numbers, dose and duration. Human or environmental safety is not established.