Anthropogenic and natural causes influencing population genetic structure of Juniperus procera Hochst. ex Endl. in the Ethiopian highlands

Abstract

Juniperus procera is economically highly important but threatened tree species. It is the only species among 67 taxa in the genus Juniperus that naturally grows in Africa and south of the equator extending up to 18°S in Zimbabwe. Ethiopia is assumed to host the largest J. procera populations, which are also believed to have high genetic variation owing to their wide ecological amplitude. This study assessed genetic variation at AFLPs of J. procera populations in the Ethiopian highlands. In the study six populations, namely Chilimo, Goba, MenageshaSuba, Wef-Washa, Yabelo and Ziquala were included. A total of 20-24 trees from each population were investigated based on 128 AFLP band positions. AMOVA revealed that most of the variation (94%) resided within populations of J. procera suggesting extensive gene flow among populations which is attributable to the outcrossing mating system and effective gene transport mechanisms of the species. However, genetic differentiation among populations was still significant (P \ 0.05), and the differentiation was significantly (P \ 0.05) correlated with geographic distance. All population pairs were significantly (P \ 0.05) differentiated except for Menagesha-Suba and Wef-Washa. These two populations also showed the highest gene diversity (H j = 0.301 and H j = 0.297, respectively). These results are in accordance with historical records that claim the establishment of the Menagesha-Suba juniper population as plantation of seedlings from Wef-Washa back in fifteenth century.

Transferability and application of microsatellites (SSRs) from <i>Juniperus communis</i> L. to <i>Juniperus procera</i> Hochst. Ex endl.

“…The lowest pairwise genetic distance which was realized between Menagesha-Suba and Wef-Washa may confirm the historical record that claims Menagesha-Suba as plantation of wildlings from Wef-Washa back in 15 th century [42,43]. These two populations were also the only undifferentiated pairs in AFLP analysis of the six populations [44]. The low differentiation between Chilimo and Yabelo, however; is contrary to the one reported by [44] between which the authors computed the highest differentiation.…”

“…These two populations were also the only undifferentiated pairs in AFLP analysis of the six populations [44]. The low differentiation between Chilimo and Yabelo, however; is contrary to the one reported by [44] between which the authors computed the highest differentiation. The result in this study is likely due to the allele size 155 bps at Jc-31 which was shared between the two populations at higher frequency.…”

Genetic diversity of AndeanPolylepis(Rosaceae) woodlands and inferences regarding their fragmentation history

“…Similarly, in a study performed by Sertse et al . (), it has been suggested that the Great Rift Valley acts as a natural barrier for gene flow for Juniperus procera Hochst. ex Endl.…”

Comparative field survival and growth of selected Ethiopian native tree species and the effect of whole soil arbuscular mycorrhizal fungi inoculation

“…The Menagesha-Suba forest currently comprises a 2667.6 ha of natural forest and 2783.7 ha of plantation forest. Menagesh suba forest was once a grass land or farmland before the then king Zeray yacob (1597-1603) ordered its reforestation by using J. procera seeds originating from Wof-Washa forest (Alemayehu et al, 2009;Sertse et al, 2011). Now the forest has matured into, according to Friis et al (2010), a kind of undifferentiated afromontane forest with canopy of J. procera and P. falcatus.…”