Assessment of genetic diversity of native species in Izu Islands for a discriminate choice of source populations: Implications for revegetation of volcanically devastated sites

Abstract

In using native species for revegetation, it is necessary choose source populations carefully to reduce the risk of planting suboptimal germplasm. To make preliminary recommendations for native species to use in the revegetation of a volcanically devastated area on Miyake Is., Japan, we investigated the genetic variation of Alnus sieboldiana, Miscanthus sinensis ssp. condensatus, and Polygonum cuspidatum var. terminalis in the Izu Islands and on the Izu Peninsula based on chloroplast DNA (cpDNA) sequence variations and amplified fragment length polymorphisms (AFLPs). The amount and pattern of differentiation differ between organelle and nuclear markers, suggesting the necessity of evaluation based on both types of markers. Within-population diversity did not vary among populations, suggesting that it does not need to be considered in the choice of a source population. The pattern and degree of differentiation varied among species, and geographical proximity did not necessarily accord with genetic similarity, suggesting that the site of an appropriate source population varies among species and should be determined empirically rather than by assuming that close proximity predicts genetic similarity. The Izu Peninsula populations deviated from the island populations in all species. Comparison of cpDNA sequences with those of related species indicates the possibility of hybridization with related species on the Izu Peninsula, suggesting that seeds collected from populations where related species live sympatrically should not be used for revegetation. These findings indicate the need to assess the genetic diversity empirically by using organelle and nuclear markers to avoid unintended consequences of genetic mixing associated with revegetation.

Genetic Diversity of <i>Lilium auratum</i> var. <i>platyphyllum</i> Endemic to the Izu Archipelago and its Relationship to a Nearby Population of <i>L. auratum</i> var. <i>auratum</i> by Morphological and SSR Analysis

“…The large difference between mainland and Izu archipelago populations shown by SSR analysis is similar to that of Iwata et al (2006). They investigated the genetic structure of Alunus sieboldiana, Miscanthus sinensis ssp.…”

Genetic structure of island populations of Prunus lannesiana var. speciosa revealed by chloroplast DNA, AFLP and nuclear SSR loci analyses

“…speciosa were much lower than that of all three species investigated by Iwata et al (2006). Furthermore, although the P. jamasalura populations investigated by Tsuda et al (2009) are not geographically isolated from each other (unlike the populations of P. lannesiana var.…”

“…speciosa, suggesting that frequent gene flow has decreased the genotypic heterogeneity between the populations. Furthermore, the among-population differentiation in the three species investigated by Iwata et al (2006) occurred mainly between the Izu Peninsula and the islands, whereas in P. lannesiana var. speciosa, the genetic differentiation was not very clear between the peninsula and the islands, especially the northern islands (Oshima, Niijima and Kouzu Islands), as illustrated in Fig.…”

“…condensatus, and Polygonum cuspidatum var. terminalis populations on the Izu Peninsula and the Izu Islands have also been investigated by analyzing cpDNA sequence variations and AFLPs (Iwata et al 2006). P. lannesiana var.…”

“…condensatus, both of which are pollinated by wind. Iwata et al (2006) suggested that the difference in the degree of genetic differentiation between the insectpollinated species P. cuspidatum var. terminalis and the two wind-pollinated species they examined might have arisen from the difference in their pollen dispersal systems, as proposed by Hamrick et al (1992).…”