FIG 1.

Validation of the experimental design and bottleneck assessment. (a) Evolution of the X. hortorum pv. vitians LM16734 population during lettuce infection, expressed as log₁₀-transformed CFU · cm⁻² of inoculated leaf. Red triangles, measured epiphytic populations following spray inoculation; green triangles, measured endophytic populations at each time point; gray bars, standard errors calculated on triplicates. (b and c) Read count correlation among Tn-seq duplicates for the X. hortorum pv. vitians LM16734 chromosome in (b) the inoculum and (c) lettuce leaves. (d and e) Volcano plots of the resampling results in (d) the inoculum versus the in vitro library condition and (e) lettuce leaves versus the inoculum condition. Plots represent the log₂ fold change of each genetic feature as a function of the negative log₁₀ of the resampling test P value. Genetic features that passed the FDR adjustment test (q value of ≤0.05) are indicated in red if they are conditionally essential and in blue if they provide a growth advantage. Nonsignificant genetic features are in gray.