Genetic basis for resistance to a granulosis virus in the potato moth Phthorimaea operculella

Evidence is presented to show that the resistance to a granulosis virus in a laboratory strain of potato moth, Phthorimaea operculella, is controlled by a single dominant autosomal gene which segregates according to simple Mendelian ratios. This may be only one of a number of genes which influence the phenotypic expression of resistance and contribute to the wide variability in response to the virus shown by field populations of the moth.