Analysis of two plant-microbe interactions in N. benthamiana

Nicotiana benthamiana plants were grown to the 8th true leaf development stage with 16 h light at 150 mol s-1 m-2 with 25/17oC day/night temperatures. Colletotrichum orbiculare strain ATCC20767 and Pseudomonas syringae pv. tabaci strain BPIC4 was grown in pure cultures to obtain syringae pv. tabaci strain BPIC4 was grown in pure cultures to obtain conidia and cells, respectively. Leaves of N. benthamiana plants were inoculated by spraying a suspension of 2 X 106 spores/ml in sterile H2O for C. orbiculare as described by Shen et al. (2001) or by infiltrating with a needle-less syringe 2 X 105 CFU/ml in sterile 10 mM MgCl2 for P. syringae pv. tabaci according to Rommens et al. (1995). For a control, healthy leaves were sprayed with sterile H2O or infiltrated with sterile 10 mM MgCl2 and then incubated under the same conditions for the same period of time as the pathogen-inoculated plants. Total RNA was extracted at 12 hours and 1, 2, 3 and 4 days after inoculation. The first and second mature leaf was excised and immediately frozen at -70 C. Keywords: Direct comparison 31 hybs total