Infected leaf tissues were excised at 6 and 24 h and immediately snap frozen. Each technical and biological replicate incorporated five leaves. Total RNA was isolated using the TRIZOL procedure (Invitrogen) and RNA quality was assessed using Nanodrop and gel electrophoresis. The library construction protocol was carried out by the contractor Novogen.  They report they did the following. Messenger RNA was purified from total RNA using poly-T oligo-attached magnetic beads. After fragmentation, the first strand cDNA was synthesized using random hexamer primers. Then the second strand cDNA was synthesized using dUTP, instead of dTTP. The directional library was ready after end repair, A-tailing, adapter ligation, size selection, USER enzyme digestion, amplification, and purification.