Plant nutrient supply is a key question in organic production of winter oilseed rape (Brassica napus L). The variation in practical cultivation is great and yield levels vary widely, while there is also a lack of knowledge regarding the need for, and profitability of, fertiliser inputs under different conditions, e.g. different precrops.
Winter oilseed rape
Nitrogen management based on precrop and site
Project manager: Maria Stenberg, Department of Soil Sciences, SLU
Project group: Ann-Charlotte Wallenhammar and Ingemar Gruvaeus, The Rural Economy and Agricultural Societies; Lena Engström, Department of Soil Sciences, SLU
The aim of this project is to investigate the possibilities of, and to develop methods, for precrop- and site-adjusted nitrogen application in organic winter rape growing. This will be done in field trials where we investigate the effects of nitrogen levels under varying conditions in order to quantify basic yield, yield potential and nitrogen requirements in relation to soil parameters. We intend to show how nitrogen uptake in winter rape is dependent on nitrogen mineralisation from the soil and to quantify the variation between sites. Factors affecting the amount of nitrogen uptake and soil mineralisation will be identified, documented and quantified. The objective will be to produce decision support data regarding nitrogen fertilisation of winter rape.
The study will consist of eight field trials per year for two years in southern and central Sweden, where nitrogen will be supplied in different amounts and strategies in the form of Vinasse, which has had good effects in the spring on autumn-sown crops. Various precrops (leys, cereals, peas, green manure leys, field beans)
- soil texture
- row spacing and
- climate conditions
- will be selected.
The trials will be laid out in existing crops in order to ensure a uniform crop stand. Each site will be documented with respect to:
- cropping history
- soil texture
- humus content and
- other soil parameters.
The status of the crop stand in all plots will be determined in autumn and at the bud stage by hand-held nitrogen sensors and at each site crop samples will be cut on these occasions.
- Root crown diameter,
- maximum rooting depth and
- incidence of pests and diseases will be monitored.
The content of mineral nitrogen in the 0-90 cm soil layer will be determined at sowing, in early spring and at harvest. Yield and seed quality, including nitrogen content, will be determined on a plot-wise basis at all sites.
Engström L, Stenberg M, Wallenhammar A-C, Ståhl P & Gruvaeus I. 2014. Organic winter oilseed rape response to N fertilisation and preceding agroecosystem. Field Crops Research 167, 94–101. https://doi.org/10.1016/j.fcr.2014.07.011
Stenberg M, Engström L, Wallenhammar AC, Gruvaeus I & Lööf PJ. 2013. Nitrogen management strategies in organic winter oilseed rape (Brassica napus L.) production. Organic Agriculture 3, 71–82. doi.org/10.1007/s13165-013-0044-0
Engström, L., Stenberg, M., Wallenhammar, A.-C., Ståhl, P . 2012. Site, preceding crop and N management effects on yield of organic winter oil seed rape. In: Abstract book. 17th Nitrogen Workshop, Wexford, Ireland. p. 216-217. (Poster).
Stenberg, M., Engström, L., Wallenhammar, A.-C., Ståhl, P., Gruvaeus, I. 2011. Nitrogen management strategies in organic winter oilseed rape (Brassica napus L.) in Sweden. The 13th International Rapeseed Congress, 5-9 June, Prague, Czech Republic. (Poster).
Stenberg, M., Engström, L., Wallenhammar, A.-C., Ståhl, P. 2011. Influence of preceding crop, site and nitrogen management on yield of organic oil seed rape (Brassica napus L.). In: Utilisation of manure and other residues as fertilizers. NJF Seminar 443. 29-30 November 2011. Falköping, Sweden. (Oral presentation).
Stenberg, M., Engström, L., Wallenhammar, A.-C., Ståhl, P., Gruvaeus, I. 2010. Nitrogen management strategies in organic winter oilseed rape (Brassica napus L.) production. In: Raghuram et al. (Eds.). N2010 5th International Nitrogen Conference “Reactive Nitrogen Management for Sustainable Development - Science, Technology and Policy”, 3-7 December 2010, New Delhi, India. Book of Abstracts p. 34. (Oral presentation).