Assessing the relationship between soil ph and the prevalence of aflatoxins in groundnuts production: implications for reducing aflatoxin contamination and improving food safety
- Author
- Chitura, Maika K.
- Title
- Assessing the relationship between soil ph and the prevalence of aflatoxins in groundnuts production: implications for reducing aflatoxin contamination and improving food safety
- Abstract
-
The contamination of groundnuts by Aflatoxin compromises the quality of groundnut kernels, particularly in regions where soil conditions favor Aspergillus sp. growth. Therefore, the core aim of this project was to find the relationship between soil potential hydrogen and aflatoxin prevalence in groundnut production, with implications for food safety and agricultural practices. The objectives were to determine how soil pH influences aflatoxin contamination, compare susceptibility between two groundnut varieties (Red Natal and Natal Common) and lastly, recommend mitigation strategies. Randomized Complete Block Design (RCBD) and factorial design was used to lay treatments. This work was done in the summer season of 2024 to 2025 at Chimuka Farm in Manicaland, Makoni district. The field experiment was conducted using soil pH levels ranging from 4.0 (strongly acidic) to 7.0 (neutral). Each variety was planted in all the 3 plots with different pH, separately and the treatments were replicated three times making them 18 in total. Groundnut plants were cultivated on an open field, and aflatoxin levels were quantified in percentage infestation per plant using visual method. Statistical analysis confirmed a highly significant relationship between soil pH and aflatoxin contamination (p < 0.001) (R2=0.9969). Results showed that acidic soils (pH 4.0–5.0) had the highest aflatoxin levels, while soils close to neutral that is pH 6.0 to 7.0 exhibited significantly lower contamination. Between varieties, Natal Common did not show a statistical difference to aflatoxin accumulation compared to Red Natal, showing that genetic factors might not influence fungal susceptibility. The study concludes that soil pH management, particularly liming acidic soils to pH ≥ 6.0, can effectively suppress aflatoxin contamination. Recommendations include promoting liming practices and integrating soil health into national aflatoxin control policies. Future research should explore long-term pH effects and economic feasibility for smallholder farmers.
- Date
- JUNE 2023
- Publisher
- BUSE
- Keywords
- aflatoxin
- groundnuts
- soil pH
- food safety
- Aspergillus sp
- Supervisor
- Professor Mandumbu
- Item sets
- Department of Crop Sciences
