Genetic Structure of Prunus africana Rosaceae (Hook.f.) Kalkm. in East Africa, as Inferred from Nuclear and Chloroplast DNA

Publikations-Art

Zeitschriftenbeitrag (peer-reviewed)

Autoren

Mbatudde, M., Nyakaana, S., Ploß, S. & Dalitz, H.

Erscheinungsjahr

2012

Veröffentlicht in

The African Journal of Plant Science and Biotechnology, 7 (1)

Seite (von - bis)

9-14

Prunus africana (Hook.f.) Kalkml., the African cherry, is an evergreen climax vegetation tree species typically reaching 25–30 m in height and occurs primarily in montane and submontane forests. In this study, the genetic structure of P. africana was analyzed using a coding chloroplast DNA region; Megakaryocyte-Associated Tyrosine Kinase Gene (MATK) and nuclear ribosomal internal transcribed spacer (nrITS) with 63 individuals in East Africa. This study detected low levels of genetic diversity as revealed by nucleotide diversity in nrDNA (�� = 0.00529) and cpDNA (0.00448). As revealed by the results of AMOVA analysis, genetic differentiation for cpDNA (FST = 0.0275) was obviously lower than for nrDNA data (FST = 0.237) in P. africana. Gene flow among populations based on nrDNA data (Nm = 2.641) was significantly higher than that based on cpDNA (Nm = 0.82). Mantel test revealed a significant correlation between genetic and geographic distances for cpDNA (r2 = 3.0 × 10-5) and nrDNA (r2 = 7.0 × 10-5). Demographic history analyses based on pair-wise nucleotide sequence mismatch distributions revealed that only the Kakamega population was in mutation-drift disequilibrium. Tajima’s D neutrality test, however, revealed significant signatures of recent population expansion in only the Kakamega population (D = –1.85646; P < 0.05). This study therefore proposes immediate ex situ and in situ conservation of P. africana populations in Mabira and Elgon forests coupled with in situ conservation of Budongo, Kakamega and Monduli forests.