Table 5.

Overview of development needs for miscanthus, how these were approached and relevant results.

	Development need	Development approaches	Main results
Growing the crop	Adaptation to different climatic conditions and to adverse and marginal site conditions	Provision (WP2) and evaluation of new breeding material (WP3, 4, 5, 6)	More than 160 miscanthus genotypes were provided for screening under field and controlled conditions. M. sinensis is more difficult to in vitro culture than M. sacchariflorus and their hybrids. Improvements in in vitro tillering methods included new surface sterilization approaches for a rhizome, node and flower meristems. Protocol adaptation and persistence achieved > 70% success rate for transfer of germplasm to in vitro.
		Better understanding of genotype x environment interactions (WP4, 5)	Recommendations for optimal choice of genotypes for all European regions.
			Northern Europe: OPM-08, -06, -10, -09
			Central Europe: OPM-09, -10, -06, -03
			Southern Europe: OPM-11, -14, -02, -03
		Develop chilling and frost tolerant genotypes (WP3) to: a) Extend productive range of miscanthus to the north and east b) Improve establishment and overwintering success c) Breed genotypes with a longer growing season	Genotypes identified with relative tolerance to chilling and frost and with high early vigor, which have potential for cultivation in regions further north and east and as starting material for breeding.
			M. sinensis and M. sinensis x sacchariflorus hybrid genotypes were more frost tolerant than M. sacchariflorus genotypes and M. x giganteus.
		Develop water-use efficient and water-stress tolerant genotypes (WP3) to: a) Extend the productive range for miscanthus further south b) Provide genotypes for marginal land	M. × giganteus has medium tolerance in terms of maintaining biomass production under drought, but recovers well when water is re-applied.
			Several genotypes were identified with improved yield compared to M. × giganteus under water-limiting conditions and with improved recovery potential after drought.
			A few genotypes are very high yielding under drought conditions despite only having medium drought tolerance. These genotypes may not perform so well under continuous drought. Of 7 genotypes with drought yields significantly higher than M. x giganteus, only 3 are in the top 10 in terms of drought tolerance. These may be suited to more southerly locations.
			Drought tolerance mechanisms include reduced water loss, such as leaf rolling, and water seeking strategies such as increased root to shoot ratio.
		Develop salinity-tolerant genotypes (WP3) for marginal land	Genotypes identified with high yields under both optimal and saline conditions.
			Starting material for breeding for salt tolerance through improved ion-exclusion activity.
			M. sacchariflorus and M. sinensis genotypes show salinity tolerance through mechanism of salt exclusion.
			Land areas with soil electric conductivity (EC) up 2.5 S/m suitable for miscanthus production.
		Develop establishment methods for marginal land and grasslands	In Germany, 80% establishment success rate for miscanthus into C3 grassland was achieved with both a no-till method and conventional pre-planting disturbance (i.e. mowing or herbicide spraying applied before planting miscanthus).
			Competitive miscanthus genotypes with tall, thick shoots to be chosen for establishment in grassland.
	Reduction of biomass production costs	Target the development of genotypes that can be established via seeds (WP2, WP5)	Commercially scalable protocols for plug planting seed-based hybrids were developed. (The project produced 100,000 plants needed for large-scale trials in three locations: UK, Germany and Ukraine).
		Identify more winter-hardy genotypes to reduce or avoid over-winter losses (WP3)	See above
		Reduce the input demands, e.g. nitrogen fertilization, of biomass production	As expected, significantly lower nutrient offtake in early senescing genotypes. This reduces the fertilizer offtake and increases biomass quality when used for heat production. Unexpectedly, leaf share not always linked to offtakes at harvest.
	Improvement of yield and biomass supply stability	Identify high-yielding genotypes adapted to different climatic conditions (WP4)	Several genotypes were identified with high yields (exceeding that of M. × giganteus) under different climatic conditions. In particular, OPTIMISC has helped identify genotypes suitable for cultivation in climatic extremes: in colder climates (Moscow), in hot climates with low water availability (Adana) and on marginal land (Aberystwyth).
		Increase yields of valuable biomass co-products (WP5, 6)	Chlorophyll and protein can be extracted before biomass goes to biogas production.
Harvesting	Reduction of harvest and logistic costs	Reduce harvest, logistic and drying costs by selection of genotypes with dry biomass at harvest (WP4, 5). Reduce pre- and post-harvest losses (WP 5)	Direct chipping with a 7.5-m cutter on a self-propelled forage harvester was the most time-efficient cutting method. However, in climates with mild winters and inadequate senescence, the indirect mowing and baling methods are more scalable due to more efficient transport and storage.
	Optimization of harvest time in terms of quality and reduction of harvest losses	Select genotypes with improved senescence patterns for dry harvestable biomass (WP4, 6)	Significant GxE (Genetic x Environment) interaction for senescence was observed. The interspecies hybrids tested senesced earlier than wild types.
Connecting to market	Biomass quality suitable for purpose of user	Understand genetic variation and effect of drought on biomass quality performance (WP 3, 6)	GxE interaction for biomass quality relevant for combustion and production of ethanol and biogas.
			Drought has a negative effect on yield but a positive effect on biomass quality. Developing drought resistant genotypes would create opportunities for growing high-quality miscanthus biomass on marginal soils (in particular dry areas).
		Diversity in biomass quality of miscanthus genotypes	There are large differences in biomass quality, and consequently performance in different chains, e.g. bioethanol and biogas, among miscanthus genotypes.
			Many genotypes have been identified with better biomass quality than M. × giganteus.
	Development of novel value chains	Biogas production was identified as a promising value chain for miscanthus biomass (WP6). Miscanthus × giganteus and novel genotypes showed high and promising potential.	October was identified as optimum biomass harvest date for Central Europe due to a very high biogas potential and sufficient cutting tolerance.
			Novel genotypes showed significantly higher specific biogas/methane yield (up to 520 ml/g DM) than M. × giganteus.
	Optimization of biomass supply chain	Develop logistics for the supply of transportable, storable and tradeable biomass (WP5)	Shorter hybrids with thinner stems had the benefits of lower moisture content (13%), higher bale weights (500 kg for M. × giganteus, vs. 650 kg) with less string breakages and ca. 20% power to pellet. However, compared to M. × giganteus, lower yielding and the pellets are 5% less dense.
			Pellets: highest bulk density for M. × giganteus biomass (OPM-09) at 810 g/l and the lowest for OPM-12 at 664 g/l.
			All miscanthus genotypes can be pelleted. M. × giganteus most difficult to pellet due to hard, stiff stems. M. sinensis OPM-12 best to pellet genotype.
			Pelleting costs 40–80 Euro/ton pellets.
	Optimization of miscanthus-based product chains	Identify cost-optimized and environmentally benign miscanthus-based product chains (WP7).	Up to 25 t (small-scale combustion, chips) and 31 t (insulation material) CO2eq./ha*a savings.
			In Central Europe cost of fuel for domestic small-scale combustion (≤ 2 ct/kWth) compete well with other fuels.
			Lowest carbon mitigation costs of -78 Euro/t CO2eq. avoided for local small-scale combustion of chips.

These are listed from top to bottom along the production to utilization chain.