Using genetic markers to identify the origin of illegally traded agarwood-producing Aquilaria sinensis trees

• Main Authors: Zheng-Feng Wang, Hong-Lin Cao, Chu-Xiong Cai, Zhang-Ming Wang
• Format: Article
• Language: English
• Published: Elsevier 2020-06-01
• Series: Global Ecology and Conservation
• Subjects: Conservation genetics; Genetic diversity; Microsatellite; SNP; RAD-Seq
• Online Access: http://www.sciencedirect.com/science/article/pii/S2351989419307942

Because of high market demand, agarwood-producing trees are frequently illegally traded in Asia and are usually priced high if they are cut from natural forests. In China, some of these traded Aquilaria sinensis trees are declared to be from natural population(s) and are said to produce agarwood “easily and fast”. To distinguish the origins and genetic differences of natural populations from cultivated ones, we used genetic markers, microsatellites and single nucleotide polymorphisms (SNP) to compare them to trees from both cultivated and known natural origin trees. Our microsatellite results revealed that the illegally traded trees were genetically close to cultivated trees, indicating that they were of cultivated origin. By separating SNPs into genic (in genic regions) and nongenic categories representing functional and non-functional SNPs, our results revealed that the genic SNP markers did not detect more genetic differences between the illegally traded A. sinensis trees and cultivated ones than the nongenic SNP markers did, indicating that they are not functionally discernable from the cultivated trees. Our study revealed that sources labelled as natural by poachers might not have natural origins, which is especially true for agarwood-producing species given their limited natural populations and their long and extensive cultivation history. Our results may reduce the public’s desire for natural agarwood from A. sinensis and other agarwood-producing species and benefit the legal agarwood trade.