Growth and Yield Response of Cowpea (Vigna unguiculata) to Bio-fertilizers Produced from Aspergillus niger and Animal waste Materials

Abstract

This study involved the production of biofertilizers from plant and animal waste materials such as saw dust, cow dung and poultry droppings inoculated with a fungus (Aspergillus niger). The saw dust and the cow dung and or poultry droppings were mixed in a ratio of 30:1. The substrates were mixed with water in line with standard method after which they were placed separately into a locally constructed bio-digester. The substrates (cow dung-saw dust mixture and or poultry droppings-saw dust mixture) were stirred daily, while they were allowed to be degraded by the fungus (A. niger). The process of degradation of the different waste materials lasted for a period of two weeks after which the nitrogen, phosphorus and potassium (NPK) contents of the bio fertilizers were analyzed. After biodegradation process, the various substrates were used to amend the soil used for growing cowpea (Vigna unguiculata). Plant growth parameters and yield of cowpea plant grown on soil amended with biofertilizers were measured and compared with those grown on soil amended with organic and inorganic fertilizers. The growth performances of the cowpea plants grown on soil amended with the two bio-fertilizers and those grown on the soil amended with inorganic fertilizer showed no significant difference at (p>0.05). The results of this study is very important in that farmers that cannot afford the expensive inorganic fertilizers can fall back on biofertilizers which are comparatively for the cultivation of food crops.