Pelleted fertiliser

Project Manager: Sofia Delin, Department of Soil and Environment, SLU.

Project Group: Annelie Lundkvist, Department of Crop Production Ecology, SLU. Lena Engström Department of Soil and Environment, SLU.

Two key requirements for success in organic crop production are increased nitrogen use efficiency of organic fertilizers and reduced weed pressure. Placement of fertilizer close to the seed row and at appropriate depth could meet both these requirements. In this study, the effects of pelleted fertilizer placement will be investigated in manually managed microplots and in larger field trials, using currently available technology. The objectives are to answer the following questions:

1. Can the nitrogen use efficiency of pelleted fertilizers be improved by better placement with regard to soil depth and distance to the seed row?
2. Is weed pressure affected by pelleted fertilizer placement?
3. What soil depth and what distance from the seed row give the best yield effects?
4. Does the level of precipitation influence the importance of soil incorporation as regards fertilizer effects on yield?

Since there is no experimental equipment available that can achieve different depths of incorporation and distances to seed rows in a desirable way, this will mainly be studied in microplots, where fertilization and sowing will be done by hand. A few treatments will be tested in larger field experiments where seed and fertilizer are drilled with a Cameleon machine, which enables different row spacing and incorporation depths.