Figure 2.

Elevated temperatures promote BPMV multiplication and cell-to-cell movement in the inoculated leaves of cv. BAT93 and larger local Hypersensitive-Response lesions are induced: (A) Representative pictures of local HR lesions on six BAT93-inoculated leaves from six different plants at 20 °C, 25 °C and 30 °C, at 7 days post-inoculation (dpi) with BPMV-WT (upper panel) and six whole plants of BAT93 at 20 °C, 25 °C and 30 °C, 14 dpi with BPMV-WT (lower panel). Mock was used as control. This experiment was performed at least 3 times with similar results. (B) Microscopic observations of BPMV-GFP accumulation in inoculated leaves of BAT93 and JaloEEP558 grown at 25 °C. The BPMV-GFP construct expressing GFP as an individual protein processed from the RNA2 polyprotein was used as a reporter of BPMV accumulation. BPMV-WT and Mock were used as control. All infection assays were made at 25 °C. Observations of GFP fluorescence (indicated by a yellow triangle) were made at 4 dpi and are representative of six BAT93-inoculated leaves sampled on six different plants. Scale bars = 250 μm. (C) Microscopic observations of BPMV-GFP accumulation in inoculated leaves of BAT93 grown at 30 °C. The BPMV-GFP construct expressing GFP as an individual protein processed from the RNA2 polyprotein was used as a reporter of BPMV accumulation. From left to right: brightfield, BPMV-GFP accumulation (green), overlay of chlorophyll fluorescence (red) and BPMV-GFP accumulation (green). BPMV-WT and Mock were used as control. All infection assays were made at 30 °C. Observations of GFP fluorescence were made at 4 dpi and are representative of six BAT93-inoculated leaves sampled on six different plants. Scale bars = 200 μm.