Traditional home-garden conserving genetic diversity: a case study of Acacia pennata in southwest China

Conserving biodiversity in human-dominated systems requires research into mechanisms that can maintain biodiversity in fragmented landscapes. Home-garden as traditional agroforestry system in many regions has shown great value in maintaining a wide range of species. Here we show that home-garden populations are also capable of maintaining high level of genetic variation. Using six polymorphic microsatellite DNA markers, we have genotyped 260 individuals of Acacia pennata , a popular wild vegetable in the tropical region of southeast Asia. Samples were collected from home-gardens and wild populations in Xishuangbanna, southwest China. Microsatellite DNA diversity in planted populations were compared with that in geographically nearby wild populations with similar population size. Over 90 % of microsatellite genetic variation in wild populations was also present in planted populations. Pairwise comparison of planted and adjacent wild population showed no significant difference in allelic diversity and heterozygosity. Analysis revealed no significant genetic differences between wild and planted populations, while four home-garden populations showed sign of bottleneck. We conclude that home-gardens show great promise in maintaining genetic diversity, and that these managed patches could be of significant conservation value in tropical regions.