Sexual dimorphism in the dioecious willow <i>Salix purpurea</i>

Premise The evolution of sex chromosomes is driven by sexual dimorphism, yet it can be challenging to document sexually dimorphic traits in dioecious plant species. At the genetic level, dimorphism identified through sequence variation between females and males associated with antagonistic different fitness optima. This study aims examine for 26 three populations Salix purpurea (a diversity panel F1 F2 populations) determine effect on biomass yield, a key trait bioenergy crops across multiple years, locations, under manipulated growth conditions. Methods Sexual was evaluated morphological, phenological, physiological, wood composition unrelated S. accessions full-sib families produced controlled cross pollinations grown replicated field trials. Results We observed timing development several that were highly predictive yield purpurea. Across all years surveyed, had significantly shallower branching angle. Male plants also accumulated more nitrogen fertilizer amendment as measured SPAD greater susceptibility rust fungus Melampsora americana family. Allometric modelling showed an location interaction stem height. Conclusions These results provide evidence certain may involved chromosome evolution.