Accelerating the domestication of a bioenergy crop: identifying and modelling morphological targets for sustainable yield increase in Miscanthus

Abstract

To accelerate domestication of Miscanthus, an important energy crop, 244 replicated genotypes, including two different species and their hybrids, were analysed for morphological traits and biomass yield over three growing seasons following an establishment phase of 2 years in the largest Miscanthus diversity trial described to date. Stem and leaf traits were selected that contributed both directly and indirectly to total harvested biomass yield, and there was variation in all traits measured. Morphological diversity within the population was correlated with dry matter yield (DMY) both as individual traits and in combination, in order to determine the respective contributions of the traits to biomass accumulation and to identify breeding targets for yield improvement. Predictive morphometric analysis was possible at year 3 within Miscanthus sinensis genotypes but not between M. sinensis, Miscanthus sacchariflorus, and interspecific hybrids. Yield is a complex trait, and no single simple trait explained more than 33% of DMY, which varied from 1 to 5297g among genotypes within this trial. Associating simple traits increased the power of the morphological data to predict yield to 60%. Trait variety, in combination, enabled multiple ideotypes, thereby increasing the potential diversity of the crop for multiple growth locations and end uses. Both triploids and interspecific hybrids produced the highest mature yields, indicating that there is significant heterosis to be exploited within Miscanthus that might be overlooked in early selection screens within years 1–3. The potential for optimizing biomass yield by selecting on the basis of morphology is discussed.

Chilling tolerance and early vigour-related characteristics evaluated in two Miscanthus genotypes

“…Giganteus was thus higher yielding compared to Goliath in Flanders, which is consistent with the findings of Larsen et al (2013) for Denmark. The higher chilling tolerance of Giganteus is unlikely to be the only factor of its higher yield, as the genotypes also differ in their morphology: Giganteus has taller and thicker stems, which is another factor correlated with the high yield in Miscanthus (Zub et al 2012a, Robson et al 2013a, Arnoult et al 2015. Moreover, the end of Goliath's growing season occurred earlier because it flowered earlier than Giganteus, which had not even flowered every year under Flemish growth conditions.…”

Metal accumulation and shoot yield of Miscanthus×giganteus growing in contaminated agricultural soils: Insights into agronomic practices

“…In North America, Europe, and Asia, some intra-and interspecific commercial cultivars have been identified for biomass production (Clifton-Brown and Lewandowski, 2002;Yan et al, 2012;Sacks et al, 2013). Much knowledge and progress have been gained in these fields in order to breed suitable genotypes depending on expected biomass uses and local environmental conditions (Gauder et al, 2012;Robson et al, 2013;Slavov et al, 2013). However, up to date, there are still very few works on the ability of Miscanthus species to grow on metal-contaminated soils.…”

Miscanthus clones for cellulosic bioethanol production: Relationships between biomass production, biomass production components, and biomass chemical composition

“…These results are encouraging for the selection of other Miscanthus clones than M. × giganteus clones, which will combine favorable biomass production and composition traits for cellulosic ethanol production. However, (i) the miscanthus aboveground biomass production is a complex trait that is determined by earliness and morphological traits, such as the canopy height, stem number per plant, and stem diameter (Robson et al, 2013;Zub et al, 2011). Regarding the miscanthus biomass composition, (ii) Allison et al (2011) highlighted variable correlations between cellulose, lignin, and hemicellulose contents.…”