Figure 5.

PR-1 Expression and Systemic Spread of TCV in Di-17 × nahG F₂ Plants.

F₂ plants derived from a Di-17 × NahG Nö cross and the Di-17 and Nö parents were TCV (T)- or mock (M)-inoculated and scored for the presence (+) or absence (−) of an HR at 4 DPI. RNAs extracted at 4 DPI from the inoculated leaves of three HR⁺ and four HR⁻ F₂ plants (chosen at random) and their parents were analyzed for the expression of PR-1, the nahG transgene, and the replication of TCV in the inoculated leaves (TCV-I) (1 to 12). The systemic spread and replication of TCV in the uninoculated tissue (TCV-U) were determined by analyzing RNA extracted from bolt tissues at 10 DPI. RNA extracted from the systemic tissues was run on a separate gel, and rRNA was used as an internal control for gel loading and transfer for both blots.