TABLE 1.
Culture-based and culture-independent characterization of different agronomic habitatsa
| Parameter | Head lettuce | Romaine | Spinach | Soil | Water |
|---|---|---|---|---|---|
| Culture based | |||||
| % surfactant producers | 29 A | 28 AB | 34 A | 15 AB | 2 B |
| Population (log CFU/g) | 4.99 A | 5.19 A | 5.39 A | 6.78 B | 4.19 A |
| Culture independent | |||||
| Chao estimate | 57.6 A | 76.7 A | 91.0 A | 294.4 B | 86.5 A |
| Faith's phylodiversity | 1.76 A | 2.20 A | 2.52 A | 6.91 B | 3.42 A |
| Diversity (Chao estimate) of pooled cultured isolates | |||||
| Surfactant producers | 9.0b | 13 A | 21.1 A | 1.6b | NAb |
| Nonproducers | 37.5 A | 69.4b | 38.4 A | 41.9 A | 68.0b |
a
Values are averages; letters denote values that are significantly different as determined by Student's t test (P < 0.05) within row comparisons.
b
At least one of the two pools was excluded due to insufficient isolates (surfactant producers <80 or nonproducers <190) or low 16S rRNA gene reads, prohibiting statistical tests.