Acquired resistance to tobacco mosaic virus transmitted to the progeny of hypersensitive tobacco.

Acquired resistance was induced in plants of hypersensitive tobacco (Nicotiana tabacum L. "Samsun NN") with a series of five induction inoculations with tobacco mosaic virus (TMV) at 2-week intervals. Selfed progeny were challenge inoculated with TMV. Lesion diameters in the progeny of induction-inoculated plants were approximately two-thirds those in the progeny of noninoculated control plants. Thus, systemic acquired resistance of hypersensitive tobacco to TMV was seed transmitted. The phenomenon was not genetic, because the progeny acquired resistance only if their parent plants had been repeatedly induction inoculated.