Warming reduces mid-summer flowering plant reproductive success through advancing fruiting phenology in an alpine meadow

Changes in reproductive phenology induced by warming are happening across
the globe with significant implications for plant sexual reproduction,
however, the response of plant reproductive efforts (number of flowers and
fruits) and success (successful fruits/total flowers) in response to
climate change have not been well-characterized. Here, we conducted a
warming and altered precipitation experiment in an alpine meadow on the
eastern Tibetan Plateau to investigate the effects of climate change on
the reproductive phenology and success of six common species belonging to
two flowering functional groups (FFGs). We found that warming advanced the
start of flowering both FFGs and the start of fruiting in mid-summer
flowering (MSF) plants. Warming reduced the reproductive efforts of
early-spring flowering (ESF) plants but did not change their reproductive
success, while the effects of warming and altered precipitation on the
reproductive efforts and success of MSF plants were year-dependent, and
the fruiting phenology regulated the response of the MSF plant’s
reproductive success to climate change. The findings highlight the
critical role of fruiting phenology in the reproductive success of alpine
plants and imply that alpine plants may reduce their fitness by producing
fewer flowers and fruits under climate warming, especially for later
flowering plants.