LB 21-187 - The rapid evolution of self-compatibility of Spartina alterniflora across latitudes in China

Thursday, August 10, 2023

5:00 PM – 6:30 PM PDT

Location: ESA Exhibit Hall

Presenting Author(s)

HH

Hao Huang

Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University
Xiamen, Fujian, China (People's Republic)

Coauthor(s)

YG

Yi Gao

Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, China (People's Republic)
FW

Fujia Wu

Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, China (People's Republic)
LX

Lili Xia

Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, China (People's Republic)
XC

Xincong Chen

Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, China (People's Republic)
YZ

Yihui Zhang

Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, China (People's Republic)
WL

Wenwen Liu

Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, China (People's Republic)

One of the most common evolutions in mating systems is the transition from self-incompatibility to self-compatibility. This evolutionary shift favors the long dispersal and colonization of flowering plants. Less opportunity for outcrossing may elevate the frequency of self-fertilization in peripheral populations, thus wide-range plants sometimes exhibit a shift from outcrossing in central populations to self-fertilization at range margins. Compare to the mating system pattern in the native range, few studies have investigated the variation of self-compatibility in the invasive range. The rapid invasion of the intertidal grass Spartina alterniflora in China during the last 40 years provides an opportunity to detect this variation pattern across latitudinal gradient. We conducted field surveys at 11 locations over 20o latitudes for four years and grew plants from the seven field locations in two common gardens at high and low latitudes with pollination treatments. Overall, we found that seed set increased linearly with latitude in the field surveys that persisted for four years. However, the small isolated patches tend to have lower seed set than meadows in low latitudes, but no significant difference in high latitudes in the field. Moreover, in the high-latitude common garden, a significant linear increased relationship between seed set and latitude (provenance) was detected only in self-pollinated treatment, while no significant linear relationships were found in the low-latitude common garden. Compared to the plants in the high-latitude common garden, plants in the low common garden presented larger variations on the first flowering day. And a significant positive relationship was found between the first flowering day and seed set in the pollination treatments. These results demonstrated that the rapid evolution of self-compatibility across latitudes in Spartina alterniflora has been modified on the coast of China, potentially reflecting the varied evolutionary rates of self-compatibility across latitudes.