Culture dependent and independent analysis of bacterial communities associated with commercial salad leaf vegetables

Table 2 Dominant members of bacterial communities associated with leafy salad vegetables as determined from pyrosequencing

Genus (or higher)	Baby spinach				Romaine lettuce				Red leaf lettuce				Iceberg lettuce				Green leaf lettuce
Genus (or higher)	C	Cs	O	Os	C	Cs	O	Os	C	Cs	O	Os	C	Cs	O	Os	C	Cs	O	Os
Pseudomonas	93.8	70.6	40.5	20.7	23.9	67.0	67.2	36.1	76.3	18.9	54.7	27.4	11.1	7.1	2.5	59.9	28.7	33.2	5.1	15.0
Ralstonia *(S, O)	-	-	-	-	-	-	-	-	11.8	76.5	1.6	38.7	14.7	82.7	0.7	20.4	60.7	60.3	-	53.4
Flavobacterium	1.5	8.9	38.9	72.1	1.1	0.5	-	0.3	0.2	0.1	18.5	7.3	3.6	0.3	-	9.4	0.3	0.1	2.0	0.5
Stenotrophomonas	-	2.3	0.1	2.8	20.2	20.0	30.8	62.2	-	0.1	-	0.2	1.9	0.5	1.0	1.3	0.5	1.1	-	0.3
Serratia	1.2	0.2	-	0.1	-	-	-	-	-	-	0.1	1.3	5.1	3.7	-	0.7	0.3	-	66.0	18.6
Erwinia	1.9	10.5	-	0.1	0.2	-	0.1	-	0.1	-	-	-	1.3	0.2	58.6	0.8	0.3	-	0.4	0.1
Xanthomonas	-	-	-	-	47.4	-	0.1	-	-	-	-	-	51.4	0.5	-	-	-	-	-	-
Pantoea	0.1	1.4	0.1	0.1	1.0	3.0	-	0.1	0.1	0.1	-	0.1	1.1	0.1	17.6	1.1	1.1	0.6	0.1	0.3
Providencia	-	-	-	-	-	-	-	-	-	-	-	0.1	0.8	0.5	-	-	-	-	13.9	3.9
Enterobacteriaceae unk..	0.8	0.9	1.0	0.2	2.1	0.5	0.7	0.4	0.3	0.1	1.3	0.4	2.1	0.3	0.5	0.6	0.6	0.2	0.8	1.8
Janthinobacterium	0.2	2.9	1.2	0.2	0.4	-	-	-	0.1	-	7.6	4.1	0.3	0.2	-	0.3	0.3	0.1	0.8	0.5
Shewanella	-	-	13.1	0.4	-	-	0.1	-	-	-	-	-	-	-	-	-	-	-	-	-
Enterobacter	0.1	0.2	-	0.3	-	0.4	-	-	0.5	0.3	-	0.5	1.4	0.6	2.4	-	-	-	2.6	1.3
Enhydrobacter	-	-	-	-	0.1	-	-	-	2.3	-	3.4	3.5	0.1	-	-	-	-	-	0.3	0.3
Leeia	-	-	-	-	-	-	-	-	1.2	1.0	-	1.5	0.1	0.5	-	1.3	1.3	0.9	-	0.8
Morganella	-	-	-	-	-	-	-	-	-	-	-	8.5	-	-	-	-	-	-	-	-
Massilia *(S)	-	-	0.1	0.1	0.2	-	-	-	1.3	-	1.7	1.3	0.4	0.1	-	0.2	0.2	0.1	0.2	0.1
Duganella	0.1	-	-	-	-	-	-	-	0.4	-	3.5	0.9	0.1	-	0.2	0.1	0.1	-	-	-
Acinetobacter *(S)	-	-	0.8	-	0.2	-	-	-	0.1	-	0.5	0.1	0.5	-	0.4	0.1	-	-	0.6	0.2
Bacillus	-	-	-	-	-	3.4	-	-	-	0.2	-	-	-	-	-	-	-	-	-	-
Streptococcus	-	-	0.2	1.5	0.1	0.1	-	-	-	-	-	-	-	0.4	-	-	0.1	0.1	-	-
Staphylococcus	-	-	0.3	0.4	0.3	0.1	-	-	-	-	-	-	1.1	-	-	-	0.5	-	-	-
Chryseobacterium	-	0.2	0.9	-	-	0.2	-	-	-	-	0.2	-	0.1	-	0.4	-	-	-	0.2	-

Samples are baby spinach, romaine lettuce, red leaf lettuce, iceberg lettuce, and green leaf lettuce in conventional (C) and organic (O) varieties. Each was also subject to surface sterilization (designated by an s) to determine just the endophytic community. Numbers are the % of the total number of sequences (mean 2,515 per sample) for each sample that were classified as a particular taxa, and only taxa accounting for > 0.1% of the sequences across all samples are shown. *indicates taxa that accounted for significantly different (p < 0.05) percentages of the total community between either sterilized and non-sterilized samples (S) or conventional versus organic production (O).

ISSN: 1471-2180