Southern blot analysis showing the presence of the pBC-phleo vector in two transformants of Aspergillus flavus. Lanes 1 and 5: strain 3357-5; lanes 2 and 6: strain 3357-5 transformed with a pBC-phleo alcA::rasA construct: Lanes 3 and 7: strain 3357-5 ΔrdiA complemented with the pBC-phleo vector containing rdiA. Lane 4: Blank. DNA in lanes 1–3 digested with BamH I and DNA in lanes 5–7 digested with Kpn I. Southern hybridization was performed using a probe amplified from plasmid pBC-phleo with the following primer pairs: BleF, 5'CCCGCTTGAGCAGACATC3' and BleR, 5'TCGTCCTGACTGGCTGCG3'.