Alternatively, the differences could selleck compound reflect sample to sample variation. Partial canonical correspondence analysis (pCCA) of T-RFLP profiles As described above, endophytic bacterial communities varied with the time of sampling and the locations of host plants. To determine the relative importance of each factor, the relative abundances of each T-RF were used to conduct pCCA of T-RFLP profiles. Figure 2 (a) shows the pCCA of T-RFLP profiles of A. viridis treating sampling dates as the environmental factor with sampling locations as covariable. Because the
Tariquidar mouse first pCCA axis is more important than the second axis, the differences between samples from May and the other two months are more significant than the differences between samples from June and July, a result which is consistent with the summary statistics of T-RFs (Table 1). This result implies rapid early changes in the development of endophytic bacterial communities, consistent Liproxstatin 1 with rapid plant growth of the host species, A. viridis. Permutation tests revealed sampling date is a significant factor (p-value = 0.0001). Figure 2 Partial Canonical Correspondence Analyses (pCCA) of T-RFLP profiles treating each of the three factors considered as the environmental factor. (a) pCCA of T-RFLP profiles
of A. viridis samples treating sampling date as the environmental factor. (b) pCCA of T-RFLP profiles of A. viridis treating sampling location as the environmental factor. (c) pCCA of T-RFLP profiles of all five host species samples treating host plant species as the environmental factor. The pCCA indicated that the three factors tested were all significant. pCCA Axes1 and 2 represent the two most important canonical correlations that explain the sample variation with pCCA Axis1 being the most important. The pCCA result of T-RFLP profiles of A. viridis treating location of host plants as environmental factor with sampling dates as covariable (Figure 2 (b)) indicated that the differences between samples from site 1 and other sites
were stronger than the differences between sites 2 and 3. Permutation tests revealed location of host plants was a significant factor (p-value = 0.0005). Extension of the analysis Molecular motor to multiple host species Having established month to month variation and sites as significant factors shaping endophytic bacterial communities in A. viridis, we asked whether the A. viridis communities were shared in other species growing at the same times in the same locations and whether those species had similar time and location influences on their community compositions. Host plant species may influence leaf endophytic bacterial communities because of their different physiological and biochemical features. Indeed, the T-RFLP patterns of A. viridis, A. psilostachya, and P. virgatum individuals were distinct (Figure 1(c)). The total number of T-RFs detected varied from 16 for R. humilis to 72 for A.