Isolation and characterization of microsatellite loci from an endangered tree species, Toona ciliata var. pubescens

Abstract

ABSTRACT. Toona ciliata var. pubescens is considered an endangered tree species native to China. In order to help develop a conservation program for this species, we evaluated its genetic diversity and population genetics. We isolated microsatellite DNA loci using streptavidin beads. A genomic library, enriched with microsatellites, was constructed and screened by sequencing. We detected 8 polymorphic microsatellite loci from the tree tissue samples. The population of T. ciliata var. pubescens used in this study is located within the Guanshan National Nature Reserve, Jiangxi Province, China. Sixty-five individuals were collected for the study. The Guanshan population was split into two subpopulations due to terrain. The number of alleles per locus ranged from 2 to 6, with expected heterozygosity from 0.2386 to 0.6772. Four of the 8 loci, except loci Tc02, Tc04, Tc05, and Tc07 showed no significant departure from Hardy-Weinberg equilibrium. The mean observed heterozygosity was 0.59. The average coefficient of genetic differentiation between the two subpopulations was quite low (F ST =

Genetic diversity of central and peripheral populations of Toona ciliata var. pubescens, an endangered tree species endemic to China

“…The reaction program was as follows: pre-denaturation at 94°C for 4 min, then 35 cycles (94°C denaturation for 1 min, 52°-55°C annealing for 0.5 min, 72°C extension for 1 min), and a final extension at 72°C for 10 min. The eight SSR loci used have been previously designed and screened by our laboratory and feature good repeatability, clear and stable amplification bands (Table 1) (Liu et al, 2006). The PCR amplification product was added with about 5 μL sampling buffer, and analyzed on an 8% polyacrylamide gel at 120 V for 3 h. The electrophoretic buffer was 1X TBE.…”

“…Genomic DNA was extracted with the improved CTAB method (Liu et al, 2006). A 15-μL reaction mix was used, comprising 1.5 μL 10X buffer, 0.3 μL 2 U/μL Taq, 2.5 mM dNTP, 10 mM primers, and 30 ng template DNA.…”

Genetic Diversity and Population Structure of Toona Ciliata Roem. Based on Sequence-Related Amplified Polymorphism (SRAP) Markers

“…Propagation by seed is most common. T. ciliata is mostly distributed in hilly and mountainous areas, and its vertical distribution range is extensive [2]. Commonly known as Chinese mahogany, the tree grows with straight trunk and produces red wood with beautiful grains [3].…”

Sequencing and analysis of the complete mitochondrial genomes of Toona sinensis and Toona ciliata reveal evolutionary features of Toona

“…There are still some issues with Toona classification, such as interspecific hybridization, that need to be addressed [33,34]. Furthermore, Toona plants have a geographically dispersed distribution in China, resulting in a scarcity of natural forests and susceptibility to natural and anthropogenic breakage, T.ciliata has now been classified as an endangered species, listed as a Class II key protected wild plant in China, and included in the Reference List of Major Cultivated Precious Tree Species in China and [35][36][37][38].…”