In planta biocontrol of soilborne Fusarium wilt of banana through a plant endophytic bacterium, Burkholderia cenocepacia 869T2

Fusarium wilt (Panama disease) caused by Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4) is a soilborne disease that severely devastates the banana industry worldwide. We aimed to isolate beneficial endophytic bacterial strains against Panama disease. From different plant species, including reeds (Phragmites australis), vetiver grass (Chrysopogon zizanioides), and banana plants (Cavendish cv. Pei-Chiao, Cavendish cv. Formosana, and Musa sapientum cv. Rose), endophytes were screened and characterized. The diversity and community of endophytes within banana plants were analyzed by PCR-denaturing gradient gel electrophoresis (DGGE). The banana tissue culture plantlets were inoculated with the candidate endophyte, Burkholderia cenocepacia 869T2, and effects of in planta biocontrol were observed. Endophytic B. cenocepacia 869T2 decreased the disease incidence of Fusarium wilt on treated banana plants to 3.4 %, comparing to 24.5 % of non-inoculated plants infected in the field test within a 7-month period. Furthermore, significant growth promoting of 869T2 inoculated banana plants was observed in field experiments. In addition to 869T2 genomic sequence data, our results suggest that the pyrrolnitrin and pyrroloquinoline quinone potential producer, B. cenocepacia 869T2, is a good biological control agent (BCA) for use in the biocontrol of Fusarium wilt and plant promotion.