The DNA contained by nuclear polyhedrosis viruses isolated from four Spodoptera spp. (Lepidoptera, Noctuidae); genome size and configuration assessed by electron microscopy.

The mol. wt. of the DNA from four nuclear polyhedrosis viruses isolated from Spodoptera littoralis, S. exempta, S. exigua and S. frugiperda were determined to be 84, 80, 68 and 74 X 10(6), respectively, by electron microscopy. The molecules were demonstrated to exist as double-stranded relaxed circular or supercoiled DNA, though linear forms of DNA were also observed.