- September 18, 2020
- Posted by: RSIS Team
- Categories: IJRIAS, Soil Science and Land Resources Management
International Journal of Research and Innovation in Applied Science (IJRIAS) | Volume V, Issue III, January 2020 | ISSN 2454–6186
ADEGOKE Adeola Florence1, AFOLAYAN Adedotun Onoyinka2*
1Adegoke Adeola Florence is a graduate of Biology from National Open University of Nigeria (NOUN), Ibadan Study Centre, Ibadan, Nigeria
2Afolayan Adedotun Onoyinka is currently the Head of Tissue Culture Unit of National Centre for Genetic Resources and Biotechnology, Apata, Ibadan, Nigeria
*Corresponding Author
Abstract— In vitro propagation is a plant tissue culture technique that provides a way to increase the rapid production of disease-free and non-contaminated planting materials, which boosts economic growth and support good health of the citizens. Being an aseptic procedure, it often helps to overcome constraints related with availability of both high-quality planting material and non-contaminated food production. The different yield of agronomic crops resulting from the contemporary agriculture practices, are often contaminated with pollutants such as heavy metals; especially during the course of their cultivation and occasionally during post-harvest processing procedures. Dioscorea sp. (Yam) is an important staple food in Nigeria with many health benefits but the presence of such noxious contaminants as heavy metals in its tubers and products renders its consumption highly detrimental to the health of its different consumers particularly human. This study was designed to conduct a comparative assessment of selected heavy metals concentrations in the dry tubers and powders originating from tissue culture hardened D. rotundata and D. alata with their respective market samples. Samples of tubers originating from yield of hardened in vitro propagated of D. rotundata and D. alata were collected from an Ibadan based Tissue Culture laboratory over a period of 28 days. Also, samples of the retailed dry tubers of both yam species were purchased concurrently from two renowned markets in Ibadan for comparison. These yam samples were all subjected to digestion and heavy metal analysis using Flame Atomic Absorption Spectrometer (AAS) to determine the levels of Pb, Cr, Cd and Ni in the digestates. The results obtained were also analyzed using XLSTAT analytical tool while pollution load indices and contamination factor were calculated. The results obtained showed that the levels of Pb, Cr, Cd and Ni in the dry tubers of in vitro yam samples (Cr=Ni=Pb=Cd; Cr = 0.000 mg/l) were significantly less than (p<0.005) those purchased from the two markets (Cr>Ni>Pb=Cd; Cr = 0.018± 0.025 – 0.030± 0.037 mg/l). Yam cultivation via micro-propagation and screen-house environments prevent undue exposure of the resulting tubers to heavy metal toxicity and as such reduces human exposure to heavy metal contaminated foodstuffs.
Index Terms— In vitro propagation, Dioscorea rotundata, Dioscorea alata, Pollutants, Heavy metals, Tissue Culture, Toxicity.