Sex and tree rings: Females neither grow less nor are less water-use efficient than males in four dioecious tree species

Females of woody dioecious species usually expend more resources on reproduction than males. Therefore, it is expected that females incur greater costs males, and, as a result, trade-offs between and growth should emerge. The aim this study to test those hypotheses by analyzing the differences genders regarding radial (basal area increment) wood carbon isotope composition (δ13C), proxy water-use efficiency. We compared these two variables in males four tree inhabiting drought-prone Mediterranean sites Spain (Pistacia terebinthus, Ilex aquifolium, Juniperus thurifera Ailanthus altissima). analyzed influence sex patterns throughout life considering stage individuals, response climate (air temperature, precipitation drought severity), δ13C during severe period. One site was studied for each 21–33 trees per were sampled site. No found any their span. significant interactions gender found, although A. altissima responsive summer (June-July) temperature. excepting P. indicating show less efficient water use events females. These results do not support broad assumption plants lower are or they respond differently variability, except terebinthus events. Further analyses could be performed other seasonally dry regions confirm reject our conclusions.