Fig 2.

Internalization of TV in romaine lettuce grown hydroponically. Feed water was inoculated with TV stock to a starting titer on day 0 of 1.25 × 10⁶ PFU/ml. The titer of the feed water was monitored throughout the 14-day study period and is reported as PFU/ml. At days 1, 2, 3, 7, and 14, roots, shoots, and leaves of romaine lettuce were harvested, homogenized with liquid nitrogen and mortar and pestle, and resuspended in 5 ml of sterile PBS. Sample homogenate was then subjected to centrifugation at 1,000 × g for 30 min, and the supernatant was tested for infectious viral particles by plaque assay. Viral titer is reported as PFU/g. Data points were the averages of three replicates. Error bars represent ±1 standard deviation.