Intercropping and cover crop effects on maize nitrogen requirement for optimal growth

• Published in: The Journal of agricultural science Vol. 160; no. 5; pp. 325 - 337
• Main Authors: Souza, S. S., Flôres, J. A., Coelho, A. P., Deienno, J. M., Lemos, L. B., Rolim, G. S.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.10.2022
• Subjects: Agricultural practices; Agricultural production; Agriculture; Cereal crops; Climate change; Corn; Cover crops; Crop yield; Cropping systems; Crops; Crops and Soils Research Paper; Experiments; Fertilization; Fertilizers; Intercropping; Legumes; Nitrogen; Potassium; Precipitation; Seeds; Crotalaria spectabilis; grain yield; Zea mays L; Urochloa ruziziensis
• ISSN: 0021-8596; 1469-5146
• DOI: 10.1017/S0021859622000478

Intercropping maize (Zea mays L.) with cover crops (Crotalaria spectabilis and Urochloa ruziziensis) is a sustainable cultivation strategy that can generate ecological benefits combined with grain yield (GY). However, cover crops may require nitrogen (N) fertilization management to be adjusted to obtain a high GY in intercropping systems. This study was carried out over 2 years in southeastern Brazil using randomized complete block design in a split-plot scheme. The plots were composed of three cropping systems: sole maize, maize + U. ruziziensis and maize + C. spectabilis. The subplots consisted of four N levels: 0, 70, 140 and 210 kg/ha. The GY of the maize + U. ruziziensis may be reduced by 13% compared to the sole maize. The GY of the sole maize increased up to 11.3 Mg/ha for 95 kg/ha of N in the first year and 6.7 Mg/ha for 169 kg/ha of N in the second year. The GY of the maize + U. ruziziensis intercropping system showed linear increments of 120 kg/ha for every 10 kg/ha of N applied. In the maize + C. spectabilis intercropping, GY increased up to 9.8 Mg/ha for 201 kg/ha of N in the first year, without any variation during the second year. The land equivalent ratio (LER) of intercropping was increased by more than 35% compared to that of sole maize, and N fertilization increased the LER of the sole maize and maize + U. ruziziensis intercropping. Maize intercropping had higher LER values with greater demand for nitrogen to obtain similar yields compared to sole maize cropping.