Growth and Biomass Yield of Brachiaria ruziziensis (Poaceae) under the Direct and Residual Effects of Fertilization with Hen Droppings at Flowering in West Cameroon

Abstract

Aim: A study was conducted at the Research and Experimental Farm (REF) of the University of Dschang with the aim of evaluating the direct and residual effects of fertilization with hen droppings on the growth and biomass yield of Brachiaria ruziziensis at flowering. Methodology: A factorial design with five levels of fertilization in terms of nitrogen in hen droppings (0, 25, 50, 75 and 100 kg N/ha) on 6 m2 (3 m x 2 m) plots in four replicates, i.e. a total of 20 experimental plots was used. Fertilization with hen droppings was done one month after the placement of the stump chips, during the first year of cultivation (direct effects). In the second year of cultivation (residual effects), no fertilization was done. Measurements of plant heights and diameters were made on 40 plants per level of fertilization. Leaf, stem and whole-plant biomass assessments were made on all plots in relation to their fertilization levels. Results: This study shows that the direct effect of fertilization in the form of hen droppings resulted in heights and diameters significantly greater than those obtained under the residual effect of fertilization. Biomasses of whole plants and their different compartments obtained under the residual effect of fertilization were significantly higher than those obtained under the direct effect of fertilization. Under the direct and residual effect of fertilization, the heights, diameters and biomasses of the fertilized plots were greater than those of the control plots. The level of fertilization corresponding to the dose of 100 kg N/ha gave the best results. Conclusion: Fertilization with hen droppings at a dose of 100 kg N/ha would be recommended for the cultivation of B. ruziziensis over a two-year period, in order to limit the use of mineral fertilizers.