Page No. : 57-63

Linum (linseed) has a long history of medicinal usage, which is documented in a number of literary sources for the treatment of common illnesses. The paucity of diversity in the available germplasm has made efforts to spread Linum in India largely unsuccessful. Therefore, in the current work, variants have been induced using the chemical mutagen Sodium Azide (SA), the physical mutagen Gamma Rays (7-Rays), and their combinations (y+SA). The doses of gamma rays were 5, 10, 15, 20, and 25 kR, the concentrations of SA were 0.10, 0.25, 0.50, 0.75, and 1.00%, and there were numerous combinations of y-rays and SA. Seed germination, seedling and plant shape, survival, variation/mutation frequency, and other factors were taken into consideration.Mutation is a sudden heritable change in the genetic material of an organism. Mutagenesis occupies a prime position in biological researches. It is the most important method for inducing alterations in qualitative and quantitative characters in a shortest possible time and provides good scope for selection. The idea for inducing mutations artificially and their subsequent utilization in crop improvement was put forward as early as 1901 by Hugo de Vries. The discovery of mutagenic role of ionizing radiation (Muller, 1927) and chemicals (Auerbach and Robson, 1942) invited a flurry of activities in the field of mutagenesis. Scientists are working on different facts to accomplish a significant breakthrough in basic understanding of mutagenesis and also its applied value for the benefits of mankind. The induction of genetic variability becomes the main source of breeding work, thus replacing conventional breeding method which depends on the naturally occurring mechanism of genetic recombination. Spontaneous mutations appear naturally in the population due to mistake during DNA replication or due to presence of various physical and chemical mutagenic agents like agricultural chemicals, industrial wastes etc. in atmosphere, sudden climatic changes like temperature etc. The mutations can be induced artificially by using different chemical and physical mutagens. Brock (1970) considered that induced mutation is an alternative to naturally occurring variations, as the source of germplasm for plant improvement programmes and as an alternative to hybridization and recombination in plant breeding. Induced mutation is one of the best methods to evolve new cultivars by producing variability at gene level.