Effects of Various Doses of Mineral Fertilizers (NPKS and Urea) on Yield and Economic Profitability of New Varieties of Zea mays L. in Faranah, Guinea

Abstract

In Faranah Province (Guinea), the ratio of supply and demand of corn is approximately 1:2. The production is low and the deficit is covered by maize importation. This study was initiated in order to improve corn production by evaluating the effects of increasing doses of mineral fertilizers on the yield and economic profitability of corn. The experiment was conducted on a farm in Kamedankoude in a split plot with three replicates. Treatments included two varieties of maize (Perta and Kilissi113) and five doses of chemical fertilizers (D0=unfertilized control, D1=300 kg NPKS+200 kg urea • hm⁻²; D2=400 kg NPKS+800 kg urea • hm⁻²; D3= 200 kg NPKS+400 kg urea • hm⁻² and D4=500 kg NPKS+600 kg urea • hm⁻²). The results showed that all the agronomic parameters increased with increasing dose of fertilizers, except for the number of ears per plant. The two varieties of corn tested produced similar yields. However, the profitability of mineral fertilizers decreased with increased doses and with value/cost ratio of 3. We recommended a mineral fertilizer dose of 300 kg NPKS + 200 kg urea. The high prices of mineral fertilizers were often barriers to intensive maize cultivation, especially for low-income farmers. This study was a contribution to rational fertilization and adapted the socio-economic conditions of the region, with the background knowledge that most farmers in the regions earned low incomes.