Investigations of genetic variation of teak (Tectona grandis Linn. f.) in Myanmar for conservation and sustainable utilization of genetic resources
Untersuchungen zur genetischen Variation von Teak (Tectona grandis Linn. f.) in Myanmar als Grundlage für die Erhaltung und nachhaltige Nutzung genetischer Ressourcen
von Yazar Minn
Datum der mündl. Prüfung:2012-09-17
Erschienen:2012-09-26
Betreuer:Prof. Dr. Reiner Finkeldey
Gutachter:Prof. Dr. Reiner Finkeldey
Gutachter:Prof. Dr. Kreft Holger
Gutachter:Prof. Dr. Dirk Hölscher
Dateien
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Zusammenfassung
Englisch
Teak (Tectona grandis) is a valuable tropical forest tree species which naturally occurs in India, Laos, Myanmar and Thailand. Ten polymorphic nuclear microsatellite markers (SSRs) and seventy-one AFLP markers (Amplified Fragment Length Polymorphisms) were used to investigate genetic variation of teak in natural populations in Myanmar for conservation and sustainable utilization of genetic resources. Adult trees and young regeneration were sampled in selectively logged and unlogged populations in four regions, each in the Northern and Southern parts of Myanmar, and two plantations in Benin. A total of 1667 samples and 1573 samples were used for SSRs and AFLPs, respectively. In general, genetic diversity within teak populations was relatively high but not significantly different between management types and between regeneration and adults. Myanmar populations were less diverse than Benin populations with SSR markers and the allelic richness was significantly higher in Southern than in Northern populations of Myanmar. Additionally, inbreeding was significantly higher in the regeneration in unlogged than in selectively-logged populations. AFLP markers showed contrasting patterns as the Myanmar populations were diverse than those of Benin, and genetic diversity in Northern populations was significantly higher than in the South of Myanmar. Furthermore, genetic diversity of adult trees was significantly higher than in the teak regeneration in unlogged populations. For both markers, cluster and structure analyses revealed two major clusters: one with northern populations and another one with southern populations of Myanmar and those of Benin. A Mantel test showed significant positive correlation between genetic and geographical distances among populations. Analyses of Molecular Variance (AMOVA) detected the highest genetic variation within populations. The FST values were significantly different among all teak populations and higher between than within the regions in Myanmar. This study suggests applying different conservation strategies for Northern and Southern Myanmar.
Keywords: teak; SSRs; AFLPs; conservation; genetic diversity; genetic differentiation; forest management; natural regeneration; selective logging
Weitere Sprachen
Teak (Tectona grandis) ist eine
hochwertige tropische Baumart und natürlich in Indien, Laos,
Myanmar und Thailand verbreitet. Mithilfe von 10 polymorphen
nukleären Mikrosatelliten- (SSRs) and 71 AFLP-Markern (Amplified
Fragment Length Polymorphisms) wurde die genetische Variation in
natürlichen Teakpopulationen in Myanmar untersucht. In
bewirtschafteten und unbewirtschafteten Populationen in jeweils
vier Regionen im Norden und Süden Myanmars wurden adulte Bäume und
ihre Verjüngung sowie in zwei Plantagen in Benin adulte Bäume
beprobt. Insgesamt wurden 1667 Proben mit SSRs und 1573 Proben mit
AFLPs untersucht.
Die genetische Diversität in den Teakpopulationen ist generell hoch
und es gibt keine signifikanten Unterschiede zwischen den
Bewirtschaftungsformen sowie zwischen den Adulten und der
Verjüngung. Die Populationen Myanmars weisen mit den SSR-Markern
eine niedrigere Diversität auf als die Populationen in Benin und
die
Schlagwörter: Teak; SSRs; AFLPs; Naturschutz; genetische Diversität; genetische Differenzierung; Forsteinrichtung; natürliche Verjüngung; Zielstärkennutzung