Response Durum Wheat to Fertility Levels under Tropical Semiarid Climatic Conditions of Southern Côte d'Ivoire

Aims: To determine the effect of NPK-fertilizer on wheat agronomic parameters and identify the couple of maximum yield and rate of fertilizer according to a response curve.

Study Design: A pot (277.75 cm²) trial was conducted in randomized complete block design composed of three replications.

Place and Duration of the Study: The study was carried out in the botanic center of Felix Houphouet-Boigny University, in Abidjan city located in south Côte d’Ivoire, during three successive cropping cycles of wheat in 2015.

Methodology: In 18 pots containing 5 kg of soil as substact, six NPK-fertilizer (15-22-22) rates (100 kgha^-1, 200 kgha^-1, 300 kgha^-1, 400 kgha^-1, 500 kgha^-1 and 600 kgha^-1) was applied as basal fertilizer. At tillering and boosting stages, 35 kgha^-1 of urea (CO(NH₂)2; 46%N) was applied for each pot respective.

Results: Wheat response was highly significant (p< 0.0001) for both linear and quadratic trends of wheat grain yield (GY) as well as for the total dry matter (TDM). The rates of 400 kgha^-1 and 425 kgha^-1 were relevant to the highest grain yields and total dry matter (11.02 and 40.35 g/pot) though, more pronounced trend was accounting significantly for 300 kgha^-1 across the successive trials.

Conclusion: Consequently, the rate of 400 kgha^-1 of NPK (15-22-22) should be the optimum recommended for durum wheat production in the forest zone of south Côte d’Ivoire. Therefore, an investigation of wheat response to K-fertilizer is still required for the improvement of plant vigor.