Thesis
Evaluation of beneficial bacteria for improved growth and resistance against Fusarium oxysporum f. sp. zingiberi in ginger (Zingiber officinale Roscoe)
University of the Sunshine Coast, Queensland
Master of Science, University of the Sunshine Coast
2008
DOI:
https://doi.org/10.25907/00348
Abstract
Severe losses in productivity in regional ginger cultivation have been caused by declining soil health and Fusarium oxysporum f. sp. zingiberi (Foz). Ongoing studies worldwide have demonstrated that plant growth promoting bacteria may increase yield, improve resistance to disease and reduce the requirement for fertilisers in a variety of crops of agronomic importance. Initially compost teas and commercial microbial inoculants were investigated as a source of microorganisms that may be beneficial to the growth of ginger. Quality control problems and associated safety issues precluded these inoculants from further study. Accordingly, reference strains of bacteria and strains isolated from the ginger rhizosphere were tested in glasshouse conditions for their plant growth promoting ability under reduced levels of fertiliser application. Bacillus F2 (field isolate), Azospirillum brasilense Sp7 and Azospirillum brasilense Sp7 combined with Bacillus coagulans NCTC 10334 significantly increased rhizome fresh weight of micropropagated ginger plants by 40.9%, 45.9% and 50% respectively. As the buffer used to apply the bacteria reduced plant growth, results indicated plant stress caused by salt in the buffer was overcome by the bacterial treatments. The aforementioned bacteria did not significantly improve the growth of ginger-plants grown from seed pieces and as such optimisation of application methods may be required. In a subsequent trial a dried alginate bead formulation of Azospirillum brasilense Sp7 significantly increased rhizome weight of ginger tissue cultured plants compared to application of a suspension of this bacterium. The alginate bead material also significantly improved the growth of micropropagated ginger plants. The importance of including appropriate controls, to identify effects of buffers and carrier materials on plant growth was repeatedly demonstrated. Antagonistic activity of bacterial isolates against Foz was also evaluated. Bacillus subtilis DAR26659 caused lysis of hyphae and also increased rhizome weight of micropropagated ginger plants by 60%, although evaluation of in planta biocontrol activity was limited by inconsistent infection of ginger plants by Foz. Improved productivity of micropropagated ginger plants might result in increased uptake of this source of disease-free planting material in the ginger industry.
Details
- Title
- Evaluation of beneficial bacteria for improved growth and resistance against Fusarium oxysporum f. sp. zingiberi in ginger (Zingiber officinale Roscoe)
- Authors
- Emily Rames
- Contributors
- D Ipek Kurtboke (Supervisor)
- Awarding institution
- University of the Sunshine Coast
- Degree awarded
- Master of Science
- Publisher
- University of the Sunshine Coast, Queensland
- DOI
- 10.25907/00348
- Organisation Unit
- School of Science and Engineering - Legacy; University of the Sunshine Coast, Queensland; GeneCology Research Centre - Legacy; School of Science, Technology and Engineering
- Language
- English
- Record Identifier
- 99449877402621
- Output Type
- Thesis
Metrics
3075 File views/ downloads
3888 Record Views