Optimizing Nitrogen Fertilization Regimes for Sustainable Maize (Zea mays L.) Production on the Volcanic Soils of Buea Cameroon

Table 2

Impact of nitrogen fertilizer rates (control–0, 50, 100, 150, and 200 kg ha⁻¹) on maize vegetative and yield parameters (Mean ± SD).

Nitrogen fertilizer rates [kg ha^−1]	Number of leaves per plant	Plant height [cm]	Stem girth	Leaf area index	Number of cobs per plant	Length of cobs [cm]	Circumference of cobs [cm]	Number of grains per cob
Control–0	18.9±0.5a	246±6a	9.3±0.3a	905±121a	1.0±0.0a	14.5±1.2b	14.8±0.5a	372±34a
50	18.8±0.4a	243±25a	9.3±0.2a	998±47a	1.1±0.1a	16.6±0.9ab	15.1±0.6a	422±19a
100	19.1±0.5a	248±23a	9.2±0.4a	1211±486a	1.0±0.1a	16.2±0.9ab	15.2±1.2a	437±37a
150	19.2±0.3a	240±35a	9.2±0.4a	909±59a	1.0±0.1a	18.0±1.2a	15.0±0.7a	449±41a
200	19.1±0.3a	259±16a	9.8±0.5a	1000±86a	1.1±0.2a	17.3±1.0a	15.2±0.9a	456±70a

Values within columns with different letters are significantly different (P < 0.05).