Gender effects on Salix suchowensis growth and wood properties as revealed by a full-sib pedigree

Among dioecious plant species, it is common for the males to grow faster than the females. In this study, we investigated the effects of gender on the growth and wood properties of Salix suchowensis Cheng ex Zhu. using a full-sib pedigree. We observed that the segregation of sex followed a 1:1 ratio and that gender significantly affected growth traits, including tree height, ground diameter, and biomass production. Additionally, the females generally performed better than the males, which is in contrast to the common scenario for dioecious plant species. There is currently relatively little information regarding gender effects on wood properties. Therefore, we also measured the basic wood density and cellulose, hemicellulose, and lignin contents. We determined that any differences between the male and female trees regarding these wood property traits were insignificant. Recent studies revealed that the sex of willow trees is controlled by a ZW sex determination system in which the female is the heterogenic gender. Because female heterogamety is relatively rare in higher plants, our findings may be relevant for characterizing the gender effects on biological performance in dioecious plants regulated by the ZW sex determination system.