Influence of Different Rates of Fertilizer and Biochar on Growth and Yield of Carrot (Daucus carota) in the Forest-Savannah Transitional Zone of Ghana

Two field studies to evaluate the effect of biochar and fertilizer application rates on soil and on the growth and yield of carrot (Daucus carota) were carried out in 2016 and 2017 at Mampong-Ashanti in the forest-savannah transitional zone of Ghana. Three rates of biochar - 0, 5 and 10 tons ha-1 and five rates of inorganic fertilizers - NPK 15:15:15 at 200 kg ha-1; P&K 50:50 at 50 kg ha-1; P&K 50:100 at 50 kg ha-1; Liquid Fertilizer at 1 L: 200 L water ha-1; and the control - were applied using 3×5 factorial arranged in a randomized complete block design with 3 replicates. The analysis showed significant (P<0.01) interaction of fertilizer × biochar on bulk density, soil porosity, soil pH, organic carbon, total nitrogen and organic matter producing both positive and negative correlations between the soil variables and on total yield, partitioning coefficient and net assimilation rate. The significant two-way interactions and correlation results underscored the need to define expected production outcomes to inform which soil management system is needed to promote sustainable agriculture as different fertilizer and biochar rates affect growth and yield parameters differently.