Local and systemic infection of a selected group of double and triple <i>ago</i> mutants by TuMV-GFP and TuMV-AS9-GFP.

<p>(A) Local infection efficiency. Panel I: infection efficiency of TuMV-GFP or TuMV-AS9-GFP is expressed relative to Col-0 (19.6 ± 3.3 foci per leaf) or to <i>dcl2–1 dcl3–1 dcl4–2</i> (2.2 ± 0.7 foci per leaf), respectively. The histogram shows the average (+ SE) of 10 plants, each with four inoculated leaves. Panel II: local infection of inoculated rosette leaves for a selected group of mutants harboring <i>ago1–27</i>. The histogram shows average (+ SE) infection efficiency of 14 plants, each with four inoculated leaves. Infection efficiency of TuMV-GFP or TuMV-AS9-GFP is expressed relative to Col-0 (4.1 ± 1.2 foci per leaf) or to <i>dcl2–1 dcl3–1 dcl4–2</i> (2.8 ± 1.1 foci per leaf), respectively. Panel III: Representative leaves of <i>ago1–27</i> single and <i>ago1–27 ago2–1</i> double mutants showing TuMV-GFP local infection foci. <i>ago1–27 ago2–1</i>, but not <i>ago1–27</i>, was infected by TuMV-AS9-GFP. Col-0 is shown for comparison. Pictures were taken at 7 dpi under UV light. (B) Systemic infection. TuMV-AS9-GFP coat protein accumulation in noninoculated cauline leaves and in inflorescence at 15 dpi. Panel I: double mutants harboring <i>ago2–1</i>. Panel II: double and triple mutants harboring <i>ago1–27</i> and <i>ago10–5</i>. The histograms show average (+ SE) of four biological replicates, expressed relative to <i>dcl2–1 dcl3–1 dcl4–2</i>. Bars with the same letter are not statistically different (Tukey’s test with α = 0.05). Panel III: in double and triple mutants harboring <i>ago1–27</i>, inflorescence samples were collected only from clusters showing systemic GFP.