Quantitative Separation of Nitrogen and Non-Nitrogen Rotation Benefits for Maize Following Velvet Bean Under Selected Soil Management Practices

• Published in: Agricultural research (India : Online) 2017-12, Vol.6 (4), p.378-388
• Main Authors: Uzoh, I. M., Obalum, S. E., Igwe, C. A., Abaidoo, R. C.
• Format: Article
• Language: English
• Subjects: Agricultural production; Agrochemicals; Biodiversity; Biomedical and Life Sciences; Cell Biology; Corn; Crop management; Crop residues; Crop yield; Cropping sequence; Crops; Fertilization; Fertilizers; Full-Length Research Article; Greenhouse effect; Greenhouses; Inoculation; Legumes; Life Sciences; Management; Nitrogen; Nutrients; Phosphorus; Plant Biochemistry; Plant Ecology; Plant Genetics and Genomics; Plant Sciences; Soil fertility; Soil management; Soils
• ISSN: 2249-720X; 2249-7218
• DOI: 10.1007/s40003-017-0272-8

It is increasingly known that factors other than legume-fixed nitrogen contribute to rotation benefit (yield advantage of legume/cereal over cereal/cereal). The contributions of nitrogen and such other factors were quantified to guide soil fertility management in legume/cereal systems. Under greenhouse conditions, the effects of returning first crop’s residue to the soil, crop sequence (velvet/maize, maize/maize) and nitrogen-fertilizer level on yield of second maize were used to separate rotation benefits into nitrogen and non-nitrogen factors, while the corresponding effects of crop sequence, mycorrhizal inoculation and phosphorus-targeted fertilization in a parallel experiment were used to disaggregate the non-nitrogen effects. Crop residue and velvet/maize had positive effects on soil nitrogen and maize yield. Nitrogen fertilizer had optimal effects at 60 kg ha −1 , while phosphorus enhanced maize yields the most when no essential nutrient was limiting. Rotation benefit was lower without (13.59%) than with (33.27%) residue. Non-nitrogen rotation benefit was 37.5%. Relative contributions of nitrogen, phosphorus, other nutrients, mycorrhiza and not-considered factors were, respectively, 34, 9, 6, 21 and 30% without residue and 68, 4, 3, 10 and 15% with residue. Crop residue management has, therefore, a strong underlying influence on legume-to-cereal rotation benefit and the relative contribution of its components.