Genetic diversity of Dyera polyphylla (Miq.) Steenis populations used in tropical peatland restoration in Indonesia

Dyera polyphylla is a native tree species of peat swamp forests in Southeast Asia. Where it has been used in peatland restoration, the trees are of uncertain genetic origin. We analysed the genetic diversity of seven populations of D. polyphylla (9–20 individual trees per population) from both natural forests and plantations on peatland farms in the Indonesian provinces of Jambi and Central Kalimantan. Using six selected primers, analysis of amplified fragment length polymorphism (AFLP) indicated that 86.5–96.8 % of loci tested (280 in total) were polymorphic, with an estimated heterozygosity H ranging from 0.29 to 0.38. The highest genetic variation was within populations, rather than among them. Cluster analysis based on Nei’s distance matrix indicated that the sampled D. polyphylla populations from Jambi and Central Kalimantan were genetically distinct. STRUCTURE analysis indicated that the wild population at Senyerang (Jambi) was the most distinct. This site and Tumbang Nusa (Central Kalimantan) deserve in situ protection and are recommended as seed sources for peatland restoration in their respective provinces. In the absence of knowledge about specific traits, it is important to retain the high genetic diversity of existing wild and planted populations of D. polyphylla revealed by our work when selecting seed sources for future peat swamp forest rehabilitation programmes.