Table 2.
IWFs from Plants Displaying ARR Inhibit the Growth of Pst in Vitro
| In Vitro Pst Growth with or without IWF
|
|||
|---|---|---|---|
| IWF Source | Col-0 | NahG | No IWF |
| Experiment 1 | |||
| Young leaves | |||
| Mock inoculated | 1084 ± 36 | 1101 ± 72 | |
| Pst inoculated | 1048 ± 48 | 1067 ± 54 | |
| Mature leaves | |||
| Mock inoculated | 1134 ± 69 | 1175 ± 186 | |
| Pst inoculated | 914 ± 57a | 1206 ± 53 | |
| 1084 ± 291b | |||
| Experiment 2 | |||
| Mature leaves | |||
| Mock inoculated | 92 ± 6.1 | 89 ± 8.8 | |
| Pst inoculated | 41 ± 9.5a | 90 ± 2.2 | |
| Pst inoculated + B | 41 ± 3.5 | ||
| 88 ± 5.8b | |||
Pst (tetracycline-resistant) bacteria (10 μL) were incubated in King's B (KB) medium ±IWF for 1 hr and then plated on KB plus rifampacin and tetracycline. The number of cfu/plate was determined 3 days later. IWFs were collected from mock-inoculated and Pst-inoculated Col-0 and NahG leaves from 4-week-old (young) and 6.5-week-old (mature) Arabidopsis plants. IWFs collected from mature Pst-inoculated Col-0 leaves were boiled (B) for 10 min before incubation with Pst.
Results are presented as means of five replicates ±sd. Student's t test indicated a significant difference in Col-0 (mock-inoculated) and Col-0 (Pst-inoculated) IWF assays (P < 0.006). Both experiments were repeated twice with similar results.
Pst alone was followed to monitor the number of bacteria present in each sample in the absence of any IWF.