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Nitrogen nutrition of soybean in Brazil: Contributions of biological N2 fixation and N fertilizer to grain yield
Open accessAbstract
There has recently been concern in Brazil whether biological N 2 fixation (BNF) is capable of meeting the increased N needs of newly released more productive cultivars, as well as doubts about the advantages of annual reinoculation of seeds. Forty experiments were performed over 3 yr in oxisols containing at least 103 cells of Bradyrhizobium g-1 in the State of Paraná, southern Brazil to estimate the contributions of BNF and of N fertilizer. The experiments were performed at two sites, Londrina and Ponta Grossa, under conventional (CT) or no-tillage (NT) systems, with two cultivars [Embrapa 48 (early-maturing) or BRS 134 (medium-maturity group)]. Treatments included non-inoculated controls without or with 200 kg of N ha-1, and inoculation without or with N fertilizer applied at sowing (30 kg of N ha-1), or at the R2 or R4 stage (50 kg of N ha-1). Compared with the non-inoculated control, reinoculation significantly increased the contribution of BNF estimated by the N-ureide technique (on average from 79 to 84%), grain yield (on average 127 kg ha-1, or 4.7%) and total N in grains (on average 6.6%). The application of 200 kg of N fertilizer ha-1 drastically decreased nodulation and the contribution of BNF (to 44%), with no further gains in yield. Application of starter N at sowing decreased nodulation and the contribution of BNF slightly and did not increase yields, while N fertilizer at R2 and R4 stages decreased the contribution of BNF (to 77%) and also yields. Estimates of volatilization of ammonia ranged from 15 to 25% of the N fertilizer applied, and no residual benefits of the N fertilizer in the winter crop were observed. The results highlight the economical and environmental benefits resulting from replacing N fertilizer with inoculation in Brazil, and reinforce the benefits of reinoculation, even in soils with high populations of Bradyrhizobium. Key words: Biological nitrogen fixation, Bradyrhizobium, inoculation, N fertilizers, ureides, soybean
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Cited by
Etemadi, F., Hashemi, M., Randhir, R., ZandVakili, O., & Ebadi, A. (2018) · The Crop Journal · doi:10.1016/j.cj.2017.12.001 · Cited by 69
Biological Nitrogen Fixation: Importance, Associated Diversity, and Estimates
do Vale Barreto Figueiredo, M., do Espírito Santo Mergulhão, A. C., Sobral, J. K., de Andrade Lira Junior, M., & de Araújo, A. S. F. (2013) · Plant Microbe Symbiosis: Fundamentals and Advances · doi:10.1007/978-81-322-1287-4_10 · Cited by 34
Metadata
- Authors
- Hungria, M., Franchini, J. C., Campo, R. J., Crispino, C. C., Moraes, J. Z., Sibaldelli, R. N. R., Mendes, I. C., & Arihara, J.
- Venue
- Canadian Journal of Plant Science
- Publisher
- Canadian Science Publishing
- Published
- 2006-10-10
- Volume
- 86
- Issue
- 4
- Pages
- 927-939
- ISSN
- 0008-4220 (ISSN-L)
- 1918-1833
- OpenAlex
- W2160229877
- Cited by
- 259
- References
- 0
- FWCI
- 6.58
- Type
- journal article
- Language
- en
- Open access
- bronze
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- CoChat. (2026). Citation check: Nitrogen nutrition of soybean in Brazil: Contributions of biological N2 fixation and N fertilizer to grain yield. https://app.cochat.ai/papers/10.4141/p05-098
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- Hungria, M., Franchini, J. C., Campo, R. J., Crispino, C. C., Moraes, J. Z., Sibaldelli, R. N. R., Mendes, I. C., & Arihara, J. (2006). Nitrogen nutrition of soybean in Brazil: Contributions of biological N2 fixation and N fertilizer to grain yield. Canadian Journal of Plant Science. https://doi.org/10.4141/p05-098
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