Heterosis for Biomass-Related Traits in Interspecific Triploid Hybrids of Willow (Salix spp.)

Species hybridization is key for the improvement of shrub willow (Salix spp.) bioenergy crops because hybrids often display heterosis yield. The development high-yielding genotypes requires numerous broad attempts at followed by field evaluation and selection stable performance. Selection improved varieties use as a crop involves full-sib progeny in family-based trials. Improving accuracy through components yield would greatly improve efficiency selection. Heterosis biomass intra- interspecific F1 F2 crosses, made between Salix sections ploidy, was examined utilizing suite morphological, physiological, chemical composition traits collected over course 12 weeks greenhouse 3 years field. Triploid families generated from diploid S. viminalis tetraploid miyabeana displayed greatest levels harvestable biomass-related growth While intraspecific purpurea diploids exhibited low these traits, produced moderate experiments. Differences trial results can largely be explained pest damage, which negatively impacted diploids. that form basis yield, including stem growth, foliar, physiological quantified, family-level differences are discussed.