Table 1.

The most abundant bacterial OTUs in cucumber rhizosphere soils treated with water (W) or vanillic acid at 0.05 μmol g⁻¹ soil (VA). OTUs were delineated at 97% sequence similarity. Only OTUs with average relative abundances >0.5% in at least one treatment were presented. Values were expressed as mean ± standard error (n = 3). OTU ID in bold indicates its relative abundance was significant different between treatments according to Welch’s t test (P < 0.05, Bonferroni corrected).

OTU ID	Phylum	Class	Genus	Relative abundances (%)
				W	VA
OTU1259	Proteobacteria	Gammaproteobacteria	Acidibacter	1.75 ± 0.24	3.72 ± 0.52
OTU394	Firmicutes	Clostridia	Clostridium sensu stricto 1	3.14 ± 0.47	1.40 ± 0.52
OTU1239	Proteobacteria	Gammaproteobacteria	Panacagrimonas	1.99 ± 0.73	2.09 ± 0.11
OTU1472	Proteobacteria	Gammaproteobacteria	Steroidobacter	1.37 ± 0.13	1.89 ± 0.12
OTU725	Acidobacteria	Acidobacteria	Acidobacteria norank	2.16 ± 0.12	0.91 ± 0.36
OTU429	Firmicutes	Clostridia	Terrisporobacter	2.18 ± 0.24	0.85 ± 0.55
OTU1435	Firmicutes	Clostridia	Clostridium sensu stricto 1	1.34 ± 0.13	0.80 ± 0.09
OTU750	Acidobacteria	Acidobacteria	Acidobacteria unclassified	1.08 ± 0.06	1.05 ± 0.05
OTU914	Bacteroidetes	Cytophagia	Cytophagaceae norank	0.99 ± 0.02	0.97 ± 0.01
OTU1125	Actinobacteria	Actinobacteria	Pseudarthrobacter	1.15 ± 0.15	0.76 ± 0.06
OTU906	Firmicutes	Clostridia	Peptostreptococcaceae unclassified	1.37 ± 0.20	0.49 ± 0.37
OTU631	Acidobacteria	Acidobacteria	Acidobacteria unclassified	0.93 ± 0.03	0.79 ± 0.03
OTU1545	Firmicutes	Clostridia	Clostridium sensu stricto 1	1.05 ± 0.16	0.47 ± 0.17
OTU654	Acidobacteria	Acidobacteria	Acidobacteria norank	0.96 ± 0.06	0.54 ± 0.11
OTU1754	Proteobacteria	Betaproteobacteria	Nitrosomonadaceae norank	0.51 ± 0.04	0.97 ± 0.10
OTU1955	Proteobacteria	Gammaproteobacteria	Luteimonas	0.59 ± 0.05	0.74 ± 0.03
OTU301	Actinobacteria	Actinobacteria	Aeromicrobium	0.50 ± 0.09	0.74 ± 0.11
OTU690	Proteobacteria	Deltaproteobacteria	Archangium	0.68 ± 0.03	0.56 ± 0.05
OTU1324	Acidobacteria	Acidobacteria	Subgroup 7 norank	0.42 ± 0.08	0.78 ± 0.11
OTU1210	Proteobacteria	Gammaproteobacteria	Thermomonas	0.63 ± 0.02	0.55 ± 0.04
OTU665	Chloroflexi	Anaerolineae	Anaerolineaceae norank	0.56 ± 0.01	0.52 ± 0.01
OTU1321	Acidobacteria	Acidobacteria	Acidobacteria norank	0.49 ± 0.04	0.58 ± 0.08
OTU148	Proteobacteria	Betaproteobacteria	Piscinibacter	0.68 ± 0.04	0.38 ± 0.13
OTU924	Firmicutes	Erysipelotrichia	Turicibacter	0.90 ± 0.11	0.17 ± 0.28
OTU1691	Proteobacteria	Betaproteobacteria	SC-I-84 norank	0.68 ± 0.03	0.37 ± 0.14
OTU1282	Proteobacteria	Betaproteobacteria	Nitrosomonadaceae norank	0.45 ± 0.03	0.57 ± 0.05
OTU1127	Actinobacteria	Actinobacteria	Marmoricola	0.42 ± 0.09	0.59 ± 0.09
OTU1074	Bacteroidetes	Cytophagia	Cytophagaceae norank	0.45 ± 0.04	0.56 ± 0.05
OTU660	Proteobacteria	Deltaproteobacteria	BIrii41 norank	0.37 ± 0.04	0.60 ± 0.05
OTU1983	Acidobacteria	Acidobacteria	Acidobacteria norank	0.57 ± 0.01	0.39 ± 0.05
OTU156	Proteobacteria	Alphaproteobacteria	Bradyrhizobium	0.41 ± 0.03	0.53 ± 0.03
OTU1649	Actinobacteria	Actinobacteria	Microlunatus	0.53 ± 0.07	0.39 ± 0.04
OTU1913	Proteobacteria	Gammaproteobacteria	Steroidobacter	0.36 ± 0.03	0.53 ± 0.06
OTU1140	Actinobacteria	Actinobacteria	Blastococcus	0.51 ± 0.03	0.36 ± 0.08
OTU704	Acidobacteria	Acidobacteria	Acidobacteria norank	0.53 ± 0.03	0.32 ± 0.05
OTU168	Acidobacteria	Acidobacteria	Bryobacter	0.58 ± 0.02	0.24 ± 0.11