Exploring the genetic profile of the bamboo populations in the fallow fields in Northern Laos utilising RAPD markers


Swidden cultivation has been common practice among Southeastern Asia though the fallow period becomes shorter these days because of increasing population pressure. The shorten interval appears to facilitate forming the secondary forest predominated by bamboo species.

The genetic profile in bamboo species of the fallow field is not fully understood while some studies have focused on secondary forest succession in terms of species richness (Fukushima et al., 2008; Sovu et al., 2009) and changing tendency of swiddening practices (Schmidt-Vogt et al., 2009) or policies on the conventional cultivation (Fox et al., 2009). Legitimate control over swidden system may result in increasing abandoned fallows to be managed for the recovery of subtropical forests.

Thus, the proscriptive current against swidden cultivation may imply that studying bamboo species in genetic regard may be pivotal. This research handles molecular identification among bamboo populations giving a clear window for understanding the distribution of clonal or sibling clumps and visualising genetic structure at each plot. In addition, the finding will aid to consider the conservation of the genetic variability in bamboo species during canopy replacement.

One of the most predominant bamboo species, Oxytenanthera parvifolia, was sampled at the montain fallow fields in Northern Laos utilising a FTA card. Polymerase chain reaction (PCR) was conducted with 5 random amplified polymorphism DNA (RAPD) markers which turned out to 61 polymorphic fragments amplified. The fragments were scored for the presence (1) and the absence (0) respectively to obtain a binary data set. AMOVA, PCA and Mantel test were performed using GenAlEx Ver.6.3 (Peakall and Smouse, 2006) These revealed the argument for genetic variability which may be ascribed to separation by distance and visualised three genetic groups representing three sampling fields. The linear correlation coefficient between geographical and genetic distance was suggested by Mantel test.



Shungo Ichinoseki