FIG 3 .

Temporal trends in the apple flower microbiome. For each time point, n = 6 (1 sample of DNA extracted in bulk from 15 flowers from each of six trees). The inner-quartile ranges are shown by the box boundaries, nonoutlier extremes are shown by the whiskers, the median is shown by the thick middle line, and outliers are shown by the outliers’ black points. Statistics were summarized across each of six trees sampled at each time point, and the communities were analyzed at the 97% OTU level. Trees 4, 5, and 6 were sprayed with streptomycin on 29 and 30 April 2010. (a) Rarefied Faith’s phylogenetic diversity of microorganisms. There were 10 resamples at a depth of 1,531 sequences for each tree at each time point. Letters indicate significant differences in phylogenetic diversity across days, assessed by analysis of variance (F = 101.56, 4 degrees of freedom [df], P < 0.001) and post hoc testing with Tukey’s HSD test (P < 0.05). (b) Variability in community structure (assessed by analysis of beta dispersion, a metric of variability). Though modest differences were detected (multivariate homogeneity of group dispersions; F = 2.34, 4 df, P = 0.08), a post hoc test revealed that only 27 and 29 April were different (Tukey’s HSD test; P = 0.09).