Maternal warming and provenance shape offspring growth of Solidago canadensis by modulating seed quality

Environmental conditions of parent plant can influence offspring performance via maternal effects. Plant provenance can also shape offspring performance owing to divergence in phenotypic adaptation among populations. While both maternal effects and provenance have been widely documented, few studies have considered them simultaneously. Here, we selected native- and invasive-range populations of Solidago canadensis, conducted a nine-year maternal warming experiment, and then performed seed germination and offspring warming experiments to examine the effects of provenance, maternal environment, and their interaction on offspring performance. Offspring from the native provenance had lower seed mass, germination rate, root/shoot ratio, and whole-plant biomass relative to those from the invasive provenance. Maternal warming significantly increased leaf dry matter content (LDMC), height growth rate, root/shoot ratio, and whole-plant biomass of offspring. Maternal warming effects also differed between provenances. Under maternal warming, the native provenance exhibited a higher germination rate and LDMC but lower chlorophyll content and specific leaf area relative to maternal ambient, whereas the invasive provenance showed a lower germination rate and no significant changes in leaf traits. These results suggest that maternal warming effects may promote early-stage growth of offspring in native populations, and highlight that provenance-dependent maternal effects are critical for predicting plant invasion under future climate change.