LAUSR

Bud burst is one of the most observable phenological stages in tree species, and its responses to environmental factors are species-specific. Nevertheless, for dioecious plants, whether they are sex-specific remains an open question, as are the underlying physiological mechanisms. Here, we investigated the effect of elevated temperature and drought on bud development, gas exchange, and carbohydrate metabolism in female and male Populus cathayana to understand how non-growing season warming and drought modifies physiological and phenological traits. Our results showed that at ambient temperature, males experienced earlier bud burst than females. Winter warming significantly delayed bud burst, and even synchronized it for both sexes because of the greater responsiveness of males. Although drought exerted little effect on the timing of bud burst, it significantly reduced bud fresh mass and limited growth by decreasing gas exchange capacity and non-structural carbohydrate accumulation; moreover, females were ...