dc.contributor.author | Ndaula Edirisa | |
dc.date.accessioned | 2024-01-17T13:59:58Z | |
dc.date.available | 2024-01-17T13:59:58Z | |
dc.date.issued | 2023 | |
dc.identifier.citation | Ndawula , E. (2023). Optimization of sterilization conditions for in vitro propagation of white yams (Dioscorea Rotundata). ( MakUD) ( Unpublished undergraduate dissertation) Makerere University , Uganda. | en_US |
dc.identifier.uri | http://hdl.handle.net/20.500.12281/18291 | |
dc.description | A dissertation submitted to the Department of Plant Sciences, Microbiology and Biotechnology, College of Natural Sciences, in partial fulfillment of the requirements for the award of the degree of Bachelor of Science in Biotechnology of Makerere University | en_US |
dc.description.abstract | White yam is an important food crop that is traditionally propagated by planting tubers. This
traditional methods is however not effective for large scale production. The alternative to this
traditional propagation is in vitro propagation. However, this in vitro propagation is also faced
with the problem of microbial contamination, as it is associated with decrease in quality of white
yams. This is because the success of in vitro propagation largely dependent on effective surface
sterilization of the explants to prevent contamination.
Currently, there is no cost effective protocol of surface sterilization conditions for in vitro
propagation of white yam, which is hindering the adoption and success of this alternative
method. The aim of this study was to develop an effective sterilization protocol for in vitro
initiation and propagation of white yam. Plant materials used were nodal segments from young
plants of the Dioscorea rotundata obtained from the screen house at National Crop Resources
and Research Institute (NACRRI). The medium used was MS and the pH was set at 5.8 ± 0.02.
viii
Cultures were maintained under a light intensity of 1,500 lux and 16-hour photoperiod and
temperature of 24 to 26 OC.
Two protocols for surface sterilization were tested i.e. Fungicides such as Carbendazim was used
in surface sterilization and non-readily available Benomyl was incorporated in media, as well as
variation in the exposure of explants to Sodium Hypochlorite and Ethanol. The most common
microbial contaminants observed in the white yam cultures were fungi. Benomyl fungicide
incorporated in media treatment was found to be the most effective in suppressing microbial
contaminants at 83% microbial elimination rate. Sterilization with 70% Ethanol and10% Sodium
Hypochlorite for 25 minutes was found to be the most effective in suppressing the microbial
contamination at 92% microbial elimination rate but was very toxic to the explants. Treating
explants for 10 min (control) was found to be ineffective in suppressing the microbial
contamination but non-toxic to explants. Subjecting the white yam explants to sterilization with
70% Ethanol and 10% Sodium Hypochlorite for 25 min was found to be the most efficient
exposure time in elimination of contamination of white yam explants. These findings will help
alleviate much of the burden associated with initiation of white yam cultures thereby reducing
cost of plantlets production. | en_US |
dc.language.iso | en | en_US |
dc.publisher | Makerere University | en_US |
dc.subject | White Ya (Dioscorea Rotundata) | en_US |
dc.subject | In-vitro propagation | en_US |
dc.subject | microbial contamination | en_US |
dc.title | Optimization of sterilization conditions for in vitro propagation of white yams (Dioscorea Rotundata) | en_US |
dc.type | Technical Report | en_US |