Morphological and physiological traits influencing biomass productivity in short-rotation coppice poplar

Abstract

Fast-growing hybrid poplar (Populus spp.) have potential as a short-rotation coppice crop grown for biomass energy. This work identifies traits for fast growth studied in an American interspecific pedigree derived from Populus trichocarpa Torr. & A. Gray × Populus deltoides Marsh. grown in the United Kingdom for the first time. The biomass yield after the first coppice rotation was estimated to range from 0.04 to 23.68 oven-dried t·ha–1·year–1. This great range suggests that genotypes from this pedigree may be used to understand the genetic basis of high yield in short-rotation coppice, which would be advantageous for informing breeding programs for biomass crops. Relationships between stem, leaf, cell traits, and biomass yield were investigated. Partial least-squares analysis was used to order the traits by importance. The traits most influential on biomass were maximum stem height throughout the growing season, basal diameter, number of stems, and number of sylleptic branches, which showed high heritability, indicating excellent potential for breeding programs. The leaf traits, leaf area, number of leaves on the leading stem, and plastochron index were also associated with an increase in biomass, leading to a better understanding of this trait.

Variation génétique de la productivité, de caractères foliaires et de la discrimination isotopique vis-à-vis du carbone chez des hybrides de peuplier cultivés sur des sites contrastés

“…No relationship has been observed between productivity and variables related to water-use efficiency (Δ), as previously described for Populus fremontii (Leffler and Evans, 1999), for TD hybrids (Rae et al, 2004) and for DN hybrids Monclus et al, 2005;Voltas et al, 2006). The lack of correlation between productivity and water-use efficiency observed earlier on young individuals was thus confirmed at larger ages and sizes, and under very different growth conditions.…”

“…The links between productivity and Δ differ according to poplar species: a positive relationship was found for Populus davidiana (Dode) Schneider (Zhang et al, 2004), whereas none was detected for Populus trichocarpa × P. deltoides (TD hybrids) and Populus deltoides × P. nigra (DN hybrids) Monclus et al, 2005;Rae et al, 2004). The lack of correlation observed for these two hybrids suggests the possibility to select genotypes displaying simultaneously a high productivity and water-use efficiency.…”

Genotypic variation in transpiration of coppiced poplar during the third rotation of a short‐rotation bio‐energy culture

“…Differences in WUE can be identified by differences in carbon isotope ratios in trees, and genotypes with high carbon isotope discrimination (Δ 13 C) have been usually related with higher biomass production and lower WUE (Farquhar, Ehleringer, & Hubick, 1989). However, the occurrence of a significant genotypic variability for productivity and for Δ 13 C (used as a proxy of WUE) in poplars and other tree species has been demonstrated, including a negative relationship between biomass and Δ 13 C (Cassasoli et al., 2004; Guehl, Nguyen‐Queyrens, Loustau, & Ferhi, 1994; Monclus et al., 2009; Zhang, Zang, & Li, 2004) or an opposite pattern (Marron et al., 2005; Rae, Robinson, Street, & Taylor, 2004). WUE in poplars is highly heritable (Monclus et al., 2005, 2006) and there is generally no trade‐off between WUE and productivity.…”

The physiological, transcriptional and genetic responses of an ozone- sensitive and an ozone tolerant poplar and selected extremes of their F 2 progeny

“…This pedigree was imported into the UK in 1999 (see Rae et al, 2009 for details). Hardwood cuttings used in this study were obtained from a field site in Hampshire, UK (see Rae et al, 2004 for details). Cuttings of uniform length and that were of uniform diameter within each genotype (i.e.…”