Isolation of large and small plaque variants of theAutographa California nuclear polyhedrosis virus

Variants of the Autographa californica nuclear polyhedrosis virus which produce large (1.4 mm) or small (0.5 mm) plaques on Spodoptera littoralis cells have been isolated. Yields of extracellular virus and polyhedra by the large plaque variant were six-fold higher and 140-fold lower, respectively, than those obtained with the small plaque variant. However the two variants could not be distinguished when Spodoptera frugiperda cells were used.