Fig. 3
Root N availability and herbivory alter foliar uptake of NO2. a Distribution of NO2-derived N, as measured by average of the total mg of 15N in root (orange bars), stem (grey bars) and leaf (green bars) tissues under low (50 mM) and high (500 mM) levels of NO3 in the presence and absence of herbivore damage (“Dam”). Data represent N = 12 plants. b Foliar uptake under 40 ppb NO2 in plants growing at low (50 mM) NO3, following damage and induction by herbivores. Light green bars are data for control plants. Dark green bars represent data for herbivore-exposed plants (“Dam”); hatched bars are data for the site of herbivore feeding, while unhatched bars are values for systemically induced leaves that were not directly consumed. Data represent N = 6 plants, and error bars are ±1 SE. For each tissue type, an asterisk (*) denotes significant effect of NO2 treatment, a dagger (†) denotes a significant effect of NO3 treatment and a section sign (§) denotes a significant effect of herbivore exposure. Full statistical results provided in Supplementary Tables 4 and 6
