Effect of complying with food safety standards on soil fertility in smallholder french bean farms in Kenya

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Research Paper 01/11/2018
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Effect of complying with food safety standards on soil fertility in smallholder french bean farms in Kenya

Mnyambo Clarice, Kironchi Geoffrey, Mbuvi Joseph, Mburu John, Wahome Samuel
Int. J. Agron. Agri. Res.13( 5), 1-8, November 2018.
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Compliance with Food Safety Standards (FSS) for production of export vegetables involves the application of manure, agro-chemicals and other inputs which influence soil fertility. A study was conducted in Kirinyaga County, Central Kenya to investigate the effect of compliance with FSS for production of French beans on soil fertility in smallholder farms. The study was done in three different agro-ecological zones; upper (Gichugu), middle (Ndia) and lower (Mwea) zones. A total of 230 farmers were selected of which 76 were compliant, 87 non-compliant and 67 non-French bean growers. Surface soil (0-30cm) was sampled from their farms to assess soil quality; samples were subjected to analysis of selected chemical properties in the laboratory. Chemical analysis results show that soil pH for Gichugu and Ndia is strongly acid (5.35-5.51), while for Mwea it is medium acid (5.83-5.97), but not significantly different among compliance levels. In all three zones and compliance levels, carbon (1.49-1.86%) and total nitrogen (0.16-0.18%) contents were not significantly different. However, Mwea had relatively higher levels of carbon content (1.86%, 1.72% and 1.79% for compliant, non-compliant and non-grower farmers respectively). Phosphorus and potassium contents were medium to high, but not significantly different among zones and compliance levels. Calcium content in the soil was medium whereas magnesium content was high in all the zones and compliance levels. Compliant farms of French beans had higher levels of copper, iron, and manganese in the soil. Therefore, the results show that compliance with FSS had no significant effect on soil fertility within the current farming and management systems. Farmers should increase levels of organic and inorganic fertilizer depending on the levels of nutrients in the soil and intensity of cropping, to increase the amounts of nitrogen and carbon in the soil and therefore, the soil quality.


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