The Genetic and Environmental Adaptation of the Associated Liana Species Derris trifoliata Lour. (Leguminosae) in Mangroves

Abstract

Derris trifoliata Lour. is an indigenous and associated liana species of mangroves in China; however, its rapid dispersal is threatening mangrove survival. To explore and evaluate their persistence in past disturbances and their potential resistance to future climate and environmental changes, 120 D. trifoliata samples were collected from three sites in Guangdong Province, China, and they were used to develop single nucleotide polymorphic markers using specific-locus amplified fragment sequencing technology. A total of 351.59 Mb reads and 97,998 polymorphic specific-locus amplified fragment sequencing tags were identified, including 360,672 single nucleotide polymorphisms. The principal component analysis, phylogenetic tree, and genetic structure all clustered the samples according to their geographic positions. The three populations showed medium genetic diversity levels and high clonal diversity, indicating that sexual propagation played vital roles in the populations’ succession, although clonal growth was intense within the populations. An association analysis revealed that 9 out of 16 markers were correlated with nitrogen, which indicated the positive roles of nitrogen in population formation and maintenance. This study provides an ecological and molecular basis for understanding the outbreaks of D. trifoliata in mangroves. To control the further expansion of D. trifoliata in mangroves, preventive and control measures should be taken against clonal growth and sexual propagation, respectively; obstructing the clonal growth, especially that of the stolon, should be mainly considered at the junctions of D. trifoliata and mangroves.