Tracking the geographical origin of timber by DNA fingerprinting: a study of the endangered species Cinnamomum kanehirae in Taiwan

Abstract

Cinnamomum kanehirae Hay. is endemic in Taiwan and is severely threatened due to intensive utilization and illegal logging. To combat illegal logging, suitable identification markers are needed, which are usable in a court of law, such as microsatellite marker for genotyping. In the present paper, a genetic fingerprinting database was generated based on 15 microsatellites, which are suitable to assess the timber's origin and its population genetic structure. The quality of DNA extractions from C. kanehirae timbers was assessed by comparing cpDNA trnL-trnF sequence lengths. The cumulative probability of identifying unrelated individuals in these microsatellites was 5.151 × 10 −17. The results indicate that the low genetic diversity is a consequence of illegal logging and that there is a significant genetic differentiation among C. kanehirae populations. It was possible to trace back the geographical origin of unknown C. kanehirae timbers based on a genetic reference database, i.e. all blind wood samples were assigned to their true geographical origins. Accordingly, microsatellites are a useful tool to identify the population origins of timbers and can be considered as a tool for combating illegal logging of C. kanehirae.

Identification of hybridization and introgression between Cinnamomum kanehirae Hayata and C. camphora (L.) Presl using genotyping-by-sequencing

“…Regarding genetic analysis, expected heterozygosity (He) is also known as gene diversity, which is a measurement for understanding the genetic variation in www.nature.com/scientificreports/ a population. In this study, the He values of C. kanehirae and C. camphora are much lower than those obtained in a previous report 12,30,32 , although all of the previous reports now reveal that the C. kanehirae had a low level of genetic diversity in Taiwan due to the overlogging and destruction or fragmentation of the natural habitat. One of the reasons explaining the lower diversity of C. camphora may be that only the widely distributed giant trees (estimated older than 100 years old) were collected and analyzed in this study.…”

“…The F is (inbreeding coefficient) is used to gauge the strength of inbreeding. Positive F is values also suggest a significant deficiency of heterozygosity in C. kanehirae and NW C. camphora , where inbreeding leads to a decrease of genetic diversity 12 , 32 . The F is of putative hybrids was negative, implying a heterozygote excess, which is possibly due to hybridization 35 .…”

Cross-amplification of microsatellite markers across agarwood-producing species of the Aquilarieae tribe (Thymelaeaceae)

“…The scale bar below indicates the genetic distance. A = Aquilaria, G = Gyrinops As data from microsatellite markers can be used to generate DNA profiles of individuals to be compared to a reference sample database (Dormontt et al 2015), it could be useful in forest timber resource identification due to its high accuracy and robustness in generating genotype data, especially for endangered plant species (Hung et al 2017).…”

Developing SSR Individual Identification System and Tracking the Geographical Origin of Timber for the Endangered Species Chamaecyparis Formosensis

“…In recent years, countries suffering from serious illegal logging have successively begun to develop DNA-based timber individual identi cation systems that can provide court evidence for conviction. The technologies can be further categorized into SSR (Simple sequence repeat)-based systems including Chamaecyparis taiwanensis 8 , Fraxinus excelsior 4 , Cinnamomum kanehirae 9 , Entandrophragma cylindricum 10 and Intsia palembanica 6 and SNP (Single nucleotide polymorphism) and INDEL (Insertion/ Deletion)-based system including Acer macrophyllum 11 .…”