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Highlights • Multi-criteria decision making model was developed to screen miscanthus for energy breeding. • Energy-related traits of miscanthus include the two aspects of agronomy and quality. • Miscanthus lutarioriparius is most suitable for producing electricity and pyrolysis bio-oil. • Miscanthus floridulus is most suitable for producing bioethanol and biogas. Abstract Biomass is the bioenergy carrier and can be converted to solid, liquid and gaseous fuels. Miscanthus , a plant type with high biomass yield potential, is a promising feedstock source for bioenergy production. However, the current expansion of miscanthus (Miscanthus spp.) production is constrained by a shortage of commercial varieties, especially those suitable for different energy usages and cultivation under adverse environmental conditions. Therefore, breeding or selecting high-biomass-yielding, high quality and stress tolerant miscanthus varieties is essential for the extension of miscanthus for bioenergy production. To effectively select elite germplasms and breed new varieties of miscanthus, it is necessary to establish a scientific evaluation method for analysing their energy potential. In this study, a multi-criteria decision making (MCDM) model was designed to evaluate the potential of miscanthus germplasms as feedstock in four energy usages including combustion for power generation (CPG), pyrolysis for bio-oil production (PBP), fermentation for ethanol production (FEP) and fermentation for biogas production (FBP). The MCDM model was constructed based on 11 sub-criteria indices, which were grouped into agronomic-related and quality-related criteria indices. The agronomic-related criteria indices include dry matter yield, canopy height, stem diameter, tiller number and base diameter/canopy diameter ratio. The quality-related criteria indices include the leaf/stem ratio, moisture content, ash content, cellulose content, hemicellulose content and lignin content. Thirty-eight representative germplasms of miscanthus were evaluated. The MCDM analysis results showed that Miscanthus lutarioriparius (especially the XiangNanDi no. 1 variety) and Miscanthus floridulus (especially A0521) are the best species for CPG/PBP and FEP/FBP, respectively. These results are superior to those calculated by the traditional energy potential assessment method, which showed that Miscanthus floridulus was the most suitable species for CPG, FEP and FBP, especially A0521 and D0624. Moreover, the analysis also indicated that D0505 (M. floridulus) can be used as a suitable parent together with XiangNanDi no. 1 to breed new varieties for CPG and PBP; XiangNanDi no. 1 can be used as an alternative parent for breeding to improve A0521 for use in FEP and FBP. [ABSTRACT FROM AUTHOR]

The intensification of livestock farming and use of arable forage crops has led to a decrease in the area of grassland used for animal husbandry. One potentially profitable use of this grassland is the production of biomass for bioenergy. The C4 grass miscanthus ( Miscanthus spp.) is considered an important biomass resource for bioenergy production; however, its cultivation is currently limited by the shortage of suitable agricultural land. The establishment of miscanthus on permanent grassland, at low densities and without destruction of the existing vegetation, could be an interesting option to consider. In this way, the expansion of miscanthus cultivation could be combined with grassland maintenance. Conventional tilling practices in miscanthus establishment (ploughing and herbicide application) on meadows can lead to loss of biodiversity. The aim of this study was to investigate efficient no-till practices for establishment and maintenance of several miscanthus genotypes on permanent grassland in Germany, focusing on the methods to improve establishment success and biomass production potential of miscanthus-supplemented grassland. A field trial was conducted at two sites to assess the effect of genotype, grassland pre-treatment (through temporary suppression of existing vegetation to reduce initial competition) and management (harvest frequencies) on miscanthus establishment and growth in grassland stands. An additional experiment with two miscanthus genotypes was set up to assess the effect of propagation method (rhizomes or pre-grown plantlets) on miscanthus establishment on grassland. Successful miscanthus establishment was achieved with no-till planting and grassland pre-treatment. Overall, miscanthus genotypes with tall, thick shoots performed better on grassland than those with short, thin shoots. Higher establishment rates were achieved through the transplanting of rhizome-derived (pre-grown) plantlets than with direct planting of rhizomes. Cutting the grassland vegetation to a stubble height of 5 cm and spraying herbicide in narrow strips before introducing miscanthus had beneficial effects on its establishment, without significant negative impact on grassland productivity. In the first three years of the study, two biomass harvests per growing season allowed a good total biomass yield from grassland to be achieved without significant impact on miscanthus growth. [ABSTRACT FROM AUTHOR]

Miscanthus is an important plant resource in China, which has energy plant value, bio-material value, and ecological value. However, the taxonomy of Miscanthus remains poorly defined. To clarify the phylogenetic relationships among the Miscanthus species found in China, here we describe their morphological characters, simple sequence repeats (SSRs), inter simple sequence repeats (ISSRs), and trnL-F and rpl16 gene sequences. We identified M. sacchariflorus and M. lutarioriparius as the closest relatives of M. sinensis and M. floridulus , all of which constituted a major group. At the molecular levels, M. lutarioriparius and M. sacchariflorus were always grouped to form a monophyletic group. M. floridulus appeared as a stable secondary clade of M. sinensis. M. nepalensis , M. nudipes , and M. paniculatus were separated from the major group and more closely linked to an outgroup. M. paniculatus fell into an isolated position outside of the major group. Therefore, our findings support placing M. sacchariflorus and M. lutarioriparius in Miscanthus , treating M. lutarioriparius as a variety of M. sacchariflorus , treating M. floridulus as a subspecies of M. sinensis. We do not support merging M. nepalensis and M. nudipes into Miscanthus and propose the recognition of Diandranthus as a standalone genus, which includes D. nepalensis and D. nudipes. We do not support merging M. paniculatus into Miscanthus , and we support the recognition of Rubimons as a separate genus, including R. paniculatus. These data should help with efforts to evaluate and use Miscanthus germplasms. • Phylogenetic relationships between Chinese Miscanthus species and its relatives. • Morphological characters, SSR, ISSR, and trnL-F and rpl16 gene sequences. • Better evaluation and utilization of Miscanthus germplasm resources. • Miscanthus species were distinguished by morphological and molecular indicators. [ABSTRACT FROM AUTHOR]