Remineralization of a Dystric Ferralsol Using Basalt and Tephra Dusts, Effective Microorganisms Manure and NPK 20-10-10 for Radish (Raphanus sativus) Production in Bamougoum (Cameroon Western Highlands)

Abstract

This paper studies the effect of basalt and tephra dusts, as alternatives to chemical fertilizers, on soil fertility and Radish (Raphanus sativus) production. The experiment was conducted in the field and in the laboratory in the years 2017 and 2018 on two separate plots so as to annul residual effects of fertilizers). The experimental design in the field was a randomized complete block design (56 m2), including five treatments and three replications: control (T0), basalt dust (T1), tephra dust (T2), effective micro-organism (EM) fertilizer (T3) and NPK 20-10-10 (T4). The main results show the following decreasing trend based on yield: T1>T3>T0>T4>T2. The best yields appear in T1 and T3 probably because they supplied the highest levels of soil nutrients to match the needs of the crops. Although T2 plants performed poorly, soil properties like pH.H2O (6.14 to 6.49), sum of exchangeable bases, base saturation, available phosphorus and cation balance were improved after tephra treatment. T2 plants might have performed poorly due to intrinsic properties of the tephra dust like low availability of trace elements compared to T1 and T3. T4 plants show the highest number of leaves, leaf area index and plant height. The Fe, Mn, Cu and Zn levels in bulbs and leaves will not pose danger of toxicity to human upon consumption and could serve as nutrient supplement for children and expectant mothers. The most profitable treatment is T1 permitting to recommend the popularization of basalt dust for radish cultivation as an alternative to chemical fertilizers.