Table 1. Comparison of the estimated OTU richness and diversity indexes of the 16S rRNA gene libraries for clustering at 97% identity.

Samplea	Shannonb	Raw reads	Clean reads	Chao	ACEc	Simpson	OTUsd
RH1	5.330	36076	35603	1276.304	1285.612	0.015	1009
BK1	5.240	35962	35587	1335.727	1337.056	0.019	978
RH2	6.228	36556	36016	1490.337	1488.857	0.004	1239
BK2	5.769	36350	35880	1443.947	1428.056	0.009	1160
RH3	5.378	36956	36388	1479.634	1479.729	0.022	1167
BK3	5.495	37005	36492	1322.793	1335.411	0.015	1103

^a Sample names 1, 2 and 3 indicated samples collected after maize had grown for 14d, 35d, and 63d, respectively. RH and BK represent rhizosphere and bulk soil.

^b Shannon diversity index calculated using Mothur.

^c Abundance-based coverage estimator calculated by Mothur.

^d Number of operational taxonomic unit calculated with Mothur.