Response of Quality Protein Maize to the Synchronization of Application and Needs for NPK Fertilizer in Acid Soils of the South-West of the DR Congo

To understand the response of quality protein maize to the different dates of NKP basal fertilizer application in the acid soils of the southwest of the DRC, an experiment was carried out during two cropping seasons (2019-2021) following a factorial design.The first factor was the season (two levels), the second was the period of fertilizer application (three levels) and the third was the variety (four levels).The experiment was repeated three times.Two varieties of quality protein maize were compared to two varieties of normal maize.Quality Protein Maize outperformed normal maize in growth and production parameters.The effects of season and date of fertilizer application strongly influenced (p < 0.0001) the growth parameters.The local and normal varieties had a longer cycle than the other varieties, with anthesis and silking interval of more than 8 days.Fertilizer application at sowing time proved to be more advantageous for having positively influenced yield.The two Quality Protein Maize varieties Mudishi-1 and Mudishi-3 recorded yields of 8 t/ha and 7.9 t/ha respectively when fertilizer was applied at sowing time during the main cropping season.However, the local variety was very sensitive (1.5 t/ha) when fertilizer application was delayed up to 30 days of growth during the short season (season B).In conclusion, the application of NPK basal fertilizers at the time of sowing resulted in a high rate of harvested plants which therefore decreases with the delayed fertilizer application.Losses are very significant when fertilizers are applied after 30 days from the start of the cycle in