Preliminary results and status of Project 1, March 2017
So far, field trials have shown that it is possible to increase biomass yield per hectare by using optimal crop rotations.
If the traditional triticale and grain crop rotation is replaced by a maize/beet/hemp/triticale or maize/winter rye/hemp (or oat) rotation, the average biomass yield is increased by 25-40%. The biomass yield is also similar or higher compared to the biomass yield of maize, but uses a greater diversity of crops and is likely to incur lower nutrient losses. Also miscanthus (once established) shows higher biomass productivity than maize. We also show that perennial grasses, although having a high radiation interception, have a low efficiency in converting the captured sunlight into harvestable biomass. The plant breeding industry could therefore improve biomass yield through a selection of plants with higher conversion efficiency. See figure 1.
Figure 1. Mean annual biomass yield for novel cropping systems optimised for biomass. Note that dark blue colors indicate increased yield compared to reference crop or crop rotation. Also note that the yield of the perennial crop miscanthus increases after the first year of establishment. For the exact composition of the systems, see Manevski et al. (2017).
Other field trials have focused on wheat and triticale varieties and the effect of different nitrogen levels on grain and straw yield. In general, the optimal nitrogen supply for these quality traits was 220 kg/ha, see figure 2.
Figure 2. 2016 yields for 1 Triticale and 9 winter wheat varieties grown at Højbakkegård in Taastrup. N1- 60, N2 – 120, N3 – 180, N4 – 240, N5 – 300 kg N/ha. Average and standard deviation of three replicates in each of four blocks.
An ongoing task in project 1 is to further identify molecular markers for straw yield and for grain quality parameters of wheat to obtain a high grain quality and a high straw quality at the same time. When identified, it will be possible to screen for cultivars with a high grain quality that still produce a high straw yield for biorefinement without problems with lodging in the crop
Figure 3. Lodging of wheat. Photo: Søren Ugilt Larsen, TI.
Project 1 have investigated strip harvesting of grain and spikes from spring barley for cattle feed followed by a combined harvesting of straw with under sown catch crops. The mixture of straw and catch crops ensiles well and is more suitable for biogas production than straw alone. This harvest strategy thus both improves biomass yield per hectare and supplies with biomass for feed production as well as energy production.
To ensure that the research results are implemented, project 1 is in contact with the suppliers of the biomass, the farmers. Project 1 calculates production cost for the biomass supply and estimates transport costs. Project 1 also calculates available biomass for biorefinement in case scenarios.
Altogether, Project 1 ensures optimal production lines for biomass for biorefinement. The project increases biomass productivity on existing agricultural land. It maintains food and feed production while simultaneously supplying biorefineries with biomass. It ensures that the production of biomass for biorefinement is economical feasible.