Biomass yield in a genetically diverse Miscanthus sacchariflorus germplasm panel phenotyped at five locations in Asia, North America, and Europe

Abstract

Miscanthus is a high‐yielding bioenergy crop that is broadly adapted to temperate and tropical environments. Commercial cultivation of Miscanthus is predominantly limited to a single sterile triploid clone of Miscanthus × giganteus, a hybrid between Miscanthus sacchariflorus and M. sinensis. To expand the genetic base of M. × giganteus, the substantial diversity within its progenitor species should be used for cultivar improvement and diversification. Here, we phenotyped a diversity panel of 605 M. sacchariflorus from six previously described genetic groups and 27 M. × giganteus genotypes for dry biomass yield and 16 yield‐component traits, in field trials grown over 3 years at one subtropical location (Zhuji, China) and four temperate locations (Foulum, Denmark; Sapporo, Japan; Urbana, Illinois; and Chuncheon, South Korea). There was considerable diversity in yield and yield‐component traits among and within genetic groups of M. sacchariflorus, and across the five locations. Biomass yield of M. sacchariflorus ranged from 0.003 to 34.0 Mg ha−1 in year 3. Variation among the genetic groups was typically greater than within, so selection of genetic group should be an important first step for breeding with M. sacchariflorus. The Yangtze 2x genetic group (=ssp. lutarioriparius) of M. sacchariflorus had the tallest and thickest culms at all locations tested. Notably, the Yangtze 2x genetic group's exceptional culm length and yield potential were driven primarily by a large number of nodes (>29 nodes culm−1 average over all locations), which was consistent with the especially late flowering of this group. The S Japan 4x, the N China/Korea/Russia 4x, and the N China 2x genetic groups were also promising genetic resources for biomass yield, culm length, and culm thickness, especially for temperate environments. Culm length was the best indicator of yield potential in M. sacchariflorus. These results will inform breeders' selection of M. sacchariflorus genotypes for population improvement and adaptation to target production environments.

Genotype by environment model predictive ability in Miscanthus

“…(2019a) and Njuguna, Clark, Anzoua, et al. (2023), namely that lower prediction accuracies tended to be observed in the more northern locations.…”

“…(2019a) and Njuguna, Clark, Anzoua, et al. (2023) considered genomic predictions either within specific environments or groups of environments.…”

“…The Msa panel consisting of 722 clones belonging to six genetic groups has also been described previously (Njuguna, Clark, Anzoua, et al., 2023). This Msa panel was genotyped and filtered removing all SNPs with missing data rate of more than 0.50 and a minimum minor allele frequency less than 0.01 (Njuguna, Clark, Anzoua, et al., 2023). This left a filtered total of 34,605 SNP RAD‐seq markers available for downstream analyses.…”

Impact of genotype‐calling methodologies on genome‐wide association and genomic prediction in polyploids

“…Phenotypic data were collected in the second and third years (2016–2017) from planting as described by Njuguna et al. (2023). We assessed three yield components of M. sacchariflorus : dry biomass yield, culm length, and the heading date (Tables 1 and 2).…”

“…These LS means were subsequently used as input for GWAS and genomic prediction. The estimated repeatability of the yield‐related traits in M. sacchariflorus ranged from 0.58 to 0.78 (Njuguna et al., 2023), suggesting that the phenotypic variation of the traits is substantially controlled by genotypic effects and was suitable for GWAS and genomic prediction (Table 2).…”