Profitability and Impact of Inorganic Fertilizers on the Maize Production in Ekona, Cameroon

Summary Declining soil fertility and low fertilizer use are the major abiotic factors limiting the maize production in Cameroon. Therefore, the design and introduction of appropriate fertilizer schemes, which would improve maize yields and provide incentives for smallholder farmers, are considered imperative. In 2018, a field experiment was conducted on the farm of the Institute of Agricultural Research for Development (IRAD) in Ekona, the south-west region of Cameroon, to investigate the profitability and impact of inorganic fertilizers on maize production. The experiment was laid out in a randomized complete block design with four replications and four treatments, using different fertilizer rates per hectare in each treatment (namely unfertilized control (T1), 50 kg urea + 50 kg N-P-K (T2), 100 kg urea + 100 kg N-P-K (T3) and 150 kg urea + 150 kg N-P-K (T4)). The results obtained indicate that all the maize growth parameters (plant height, number of leaves per plant, stem girth and leaf area) and yield components considered (cob length, cob diameter and test weight of 100 grains) were significantly (P < 0.05) higher in T4 than T1. The grain yields recorded ranged from 4.09–5.88 t ha−1 and were also statistically (P < 0.05) higher in T4 than T1. The incremental income based on the fertilizer use was the highest in T4, followed by T3 and T2. The value cost ratio (VCR) was greater than 2 in all the treatments and was found to be highest in T2 (3.15), followed by T4 (2.52) and T3 (2.49). As T2, T3 and T4 did not differ statistically (P > 0.05), all the fertilizer rates considered were economically viable, but T4 provide the most cost-effective due to its higher grain yields and incremental income.