Evaluation of Integrated Fertilizer Application and Genotypes on Growth and Yield Components of Daucus carota in Derived Savannah Zone

A two-year field experiment was conducted in 2018 and 2019 at the Teaching and Research Farm, Faculty of Agriculture, University of Nigeria, Nsukka, Southeastern Nigeria, to evaluate the effects of organic and inorganic fertilizer combinations and carrot genotypes on seedling emergence, growth, and yield of carrot (Daucus carota L.). The experiment was a 5 × 3 factorial arranged in a randomized complete block design with four replications. Five fertilizer treatments comprised control, 20 t/ha poultry manure, 20 t/ha pig manure, 10 t/ha poultry manure + 200 kg/ha NPK 15:15:15, and 10 t/ha pig manure + 200 kg/ha NPK 15:15:15. Three genotypes, Safety Touchon France, Carotte Touchon AM, and Carotte Touchon ETS, were evaluated. In 2018, fertilizer treatments significantly affected seedling emergence, harvest index, whole-plant biomass yield, and root yield. The application of 10 t/ha poultry manure + 200 kg/ha NPK produced the highest whole-plant biomass yield (6.0 t/ha), root yield (3.5 t/ha), harvest index (65.4%), and marketable yield (97.0%). In 2019, 20 t/ha poultry manure produced the highest whole-plant biomass yield (8.5 t/ha), root yield (5.7 t/ha), and harvest index (67.5%). Genotypic effects were generally limited, although significant differences occurred for selected traits. Carotte Touchon AM recorded comparatively higher biomass and root yields, while Safety Touchon France produced more harvested roots. Overall, 10 t/ha poultry manure + 200 kg/ha NPK 15:15:15 provided a consistent yield advantage and is recommended for carrot production under the study conditions.