Figure 2.

Isolation of Fungi from Symptomatic Leaves of Transgenic ‘Greensleeves’ Apple Trees and Reinoculation on Apple.

(A) Three fungal strains (R1, R2, and R3, shown to be Alternaria spp; Supplemental Figure 1) isolated from symptomatic transgenic apple leaves.

(B) PCR analysis of the AMT gene encoding AM toxin synthetase for AM toxin biosynthesis. Wild-type strain M-71 of A. alternata apple pathotype (Johnson et al., 2000) was included as a positive control. β-Tubulin was used as a control housekeeping gene. Note lack of an AMT signal in R1-R3 strains.

(C) Disease symptoms on wild-type control (CK) and antisense line A10 after reinoculation with R1, R2, and R3 isolates. Sterile water was used as a negative control. Bars = 1 cm.

(D) Percentage of infected leaves in the wild-type control and A10 after reinoculation with R1, R2, and R3, respectively. Data are mean ± sd of five biological replicates with 50 leaves pooled from two trees per replicate. **P < 0.01 (Student’s t test).