The Potential of Cassava (Manihot esculenta Crantz) Peels as an Organic Fertilizer

Abstract

Cassava peels are in large quantity and practically of no economic value in many developing nations such as Cameroon, where cassava is widely consumed and processed far beyond other crops. Cassava peels might be used in those countries to face declining soil fertility and soil erosion. This study aimed to evaluate the composting of cassava peels and the effect of the increasing quantity of cassava peels in the bin during the process of composting and to assess some physico-chemical qualities, biological properties and the phytotoxicity of the produced composts. After three months of composting the produced composts (C1; C2; C3 and C4) had a dark brown color, relatively dry, uniform structure and its texture were similar to the soil's texture. The electrical conductivity of the various composts was in between 1499 and 1924 µS.cm-1. The pH (6.50-6.73), was slightly acid, favorable for the cultivation of sweet pepper. The composts were rich in minerals (Mg2+; Ca2+; K+; and Na+) and poor in heavy metals such as (Cu, Zn and Mn). The composts C/N ratios were between 13.15 to 13.42. The produced composts showed a germination index and the rate of germination higher than 80% at all amounts, indicating the absence of phytotoxicity. The increased amounts of cassava peels did not alter the process of composting and increased the fungal and bacterial populations. In conclusion, cassava peels are good substrates that can be used to produce stable and inclusive organic fertilizers, with high nutrient content, and less hazardous material which could be used in farms to remediate declining soil fertility and to promote sustainable agriculture.