Genetic improvement of pyrethrum (Tanacetum cinerariifolium Sch. Bip.) through gamma radiation and selection of high yield stable mutants through seven post-radiation generations.

The mutagenesis changed traits mean in positive or negative directions. Pyrethrum plant is highly sensitive to gamma irradiation and produced a high range of variability in the qualitative and quantitative traits. The mutagenesis changed the mean of traits in both positive and negative directions. Due to mutagenic efficacy, two mutants 7 (40 Gy-5), and 10 (40GY-8) were expressed high performance for pyrethrin percent i.e., 87.23 and 59.78% improvement over the check variety 'Avadh', with synchronous flowering. These two mutants are in the pipeline for release as a variety for cultivation in the North Indian plains.