Figure 3: Phenotypic characterization of the ALT7-disrupted and ALT7- complimented strains. (A) Vegetative growth and colony morphology of wild type (WT), ALT7-disrupted (T1) and ALT7-complemented (T1C) strains on PDA. (B) The strains were grown on PDA at 25°C and colony diameters were recorded daily. The bars represent the means ± standard deviation of the diameters of three replicates. (C) Vegetative growth and colony morphology of the wild type (WT) and ALT7-disrupted (T1) strains on medium containing a high concentration of AAL-toxin. The high-toxin medium contains 50 µg/ml of AAL-toxin. Tomato leaf discs of susceptible (Aichi-first) and resistant (Micro-Tom) cultivars were also incubated on the medium as a control to confirm the activity of the toxin. Note that only the susceptible leaf disc showed necrosis. (D) Detection of ALT7 transcripts in the transformants. Total RNA extracted from the wild type and the transformants cultured in 50 ml of PDB for 3 days with shaking was used as templates for RT-PCR. The primers ALT7inF and ALT7inR amplify an internal fragment (400 bp) of ALT7. Primers specific for ß-tubulin were used as a positive control.