Extremely low genetic diversity and extensive genetic admixture at the northern range margins of Bombax ceiba. (June 2015)

• Record Type: Journal Article
• Authors: Dai, Seping; Wang, Shuqiong; Ruan, Lin; Zhou, Yubing; Wu, Wei; Liu, Ying; Shi, Suhua; Zhou, Renchao
• Is Part Of: Biochemical systematics and ecology. Volume 60(2015)
• Page Start: 177
• Page End: 185
• Publication Date: 2015-06
• Subjects: Bombax ceiba -- Genetic diversity -- Genetic admixture -- Nuclear genes -- Population differentiation -- Range margin; Chemotaxonomy -- Periodicals; Biochemical variation -- Periodicals; Ecology -- Periodicals; Biochemistry -- Periodicals; Ecology -- Periodicals; Chimiotaxinomie -- Périodiques; Variation biochimique -- Périodiques; Écologie -- Périodiques; 578.012
• DOI: 10.1016/j.bse.2015.04.022
• Languages: English
• ISSNs: 0305-1978

Abstract

Abstract: Understanding the evolutionary processes in species at the margins of their range is of great significance, because marginal populations may harbor local adaptations and will initiate further expansion in response to changes in the environment. Here we examined genetic variation in two nuclear genes and one chloroplast intergenic spacer in 13 northern marginal populations and one geographically central population of Bombax ceiba, a tree distributed mainly in tropical regions. Our results revealed an extremely low level of genetic diversity in each population at the northern margin of its range and strong genetic differentiation between southern China and South Asia. Cultivated and natural populations showed no significant differences in genetic variability. Genetic admixture in a nuclear gene was detected in 10 of the 13 populations at the northern margin of their range. The founder effect, in which a small number of individuals colonize the northern margins of its range, may explain the extremely low genetic diversity. During the establishment of new populations, different source populations may mix and undergo further genetic drift and differentiation. This study indicates that patterns of genetic diversity in tropical species at the margin of their range may also be severely influenced by founder effects. Highlights: Extremely low genetic diversity was detected in marginal populations of Bombax ceiba . Strong population differentiation was revealed between different regions. Cultivated and natural populations showed no significant differences in diversity. Genetic admixture was extensive in the marginal populations.