Fig. 4.

(a) PFGE of WT AcMNPV and Ac-FPm BV DNA digested with AvrII and EcoNI at different passages. DIP formation was delayed in Ac-FPm compared with AcMNPV. The left arrow at 54 kb indicates the defective genome formation at passage 16 and the two right arrows at 54 and 59 kb indicate the defective genome formation at passage 19. (b) PFGE of WT AcMNPV BV DNA digested with EcoNI. The arrows on the left indicate the DNA fragment sizes (kb) corresponding to standard DNA of WT AcMNPV and the arrows on the right indicate the sizes of DNA bands appearing due to the formation of DIPs at passage 32. Lanes: L, λ DNA ladder (kb); WT, WT AcMNPV DNA; FPm, Ac-FPm DNA; W1, WT AcMNPV DNA at passage 1; W32, WT AcMNPV DNA at passage 32.