[en] White marigold of the (Tagetes erecta L. compositae) is an important ornamental crop suited for pot and bed plants. It suffers from the problem of low seed viability and poor seed germination. The technique of in vitro regeneration has already been standardized for production of large scale quality planting materials of white marigold. For inducing greater genetic variability, seeds collected from in vitro raised plants were included in a gamma ray induced mutation breeding programme. The main objective of the present experiment was to study the radiosensitivity of tissue culture raised seeds