In vitro bacterization of banana (Musa spp.) with native endophytic and rhizospheric bacterial isolates: Novel ways to combat Fusarium wilt

• Published in: European journal of plant pathology Vol. 151; no. 2; pp. 371 - 387
• Main Authors: Kavino, M., Manoranjitham, S. K.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-06-2018; Springer Nature B.V
• Subjects: Agriculture; Bacillus subtilis; Bananas; Biomedical and Life Sciences; Consortia; Cultivars; Disease control; Ecology; Endophytes; Field tests; Fruits; Fusarium; Fusarium oxysporum; Inoculation; Life Sciences; Microorganisms; Micropropagation; Minerals; Plant growth; Plant Pathology; Plant Sciences; Plantations; Plantlets; Pseudomonas fluorescens; Rooting; Salts; Tissue culture; Vitamins; Wilt; spp; wilt race 1; Growth; bacterization; Micropropagation; Yield; Biocontrol
• ISSN: 0929-1873; 1573-8469
• DOI: 10.1007/s10658-017-1379-2

Compared to conventional planting material, micropropagated plantlets are highly susceptible to
Fusarium
wilt because they are free from beneficial root inhabitants. We aimed to introduce mixtures of beneficial microbes in the plantlets in the rooting medium under
in vitro
conditions rather than by field applications. Endophytes and rhizobacteria from different banana cultivars and plantation areas were screened and characterized. Under
in vitro
conditions, banana tissue culture plantlets were bacterized with the prospective endophytes,
Bacillus subtilis
strain EPB56 and EPB10 and the rhizobacteria,
Pseudomonas fluorescens
strain Pf1 and effects of
in vitro
bacterization were investigated against
Fusarium oxysporum
f. sp.
cubense
race 1 under glasshouse and field conditions. Inoculation of bananas during micropropagation allowed for the omission of minerals and salts as well as vitamins from the growing media while resulting in plantlets close to double size compared to the controls with full strength media. All endophyte and rhizobacteria strains tested resulted in significant reductions in
Fusarium
infection in the glasshouse and field and in significantly better plant growth. The three-way combination of bacteria resulted in 78% disease reduction and more than doubled the yields compared to the untreated controls across two field experiments. Three-way inoculation led to yields of 23 and 24 kg/ bunch compared to chemical disease control (13; 15 kg/bunch) and untreated controls (10; 13 kg/bunch) in the two field experiments. Under glasshouse conditions, activity of defence enzymes was significantly increased by all inoculation treatments. Inoculation
in vitro
led to the establishment of the microorganisms in the plant system before delivering to the farming community. Micropropagation combined with the establishment of a beneficial microbial consortium should complement the micropropagated plants for easier adaptation under field conditions.