The utility of chemical and radiation induced mutations in tetraploid wheat

The present investigation was conducted with the main objective of studying the extent of genetic variability released through recombination, induced mutation and their combination for yield and its attributing traits in tetraploid wheat. The material consisted of segregating populations (F₂, M₂ and F₂M₂) developed from Triticum dicoccum wheat variety DDK1025 and T. durum wheat variety HD4502 after subjecting to EMS and γ-rays treatment. Among mutagen treated populations γ-rays induced more reduction in germination and survival percentage and mean plant height than EMS. Analysis of variance revealed highly significant differences among the populations for all the characters studied. An upper limit of range was more in M₂ compared to F₂ and F₂M₂ populations for all the characters except for days to 50% flowering and number of productive tillers/plant. In general, the γ-rays irradiated populations recorded highest PCV and GCV for all the characters except for plant height, spike length and spikelets/spike indicating greater scope for selection and improvement of these characters in desired direction. Most of the characters exhibited high heritability except spike length in all segregating populations. In general, the number of favorable correlations and higher strength of positive correlations were appeared to be more in F₂M₂ populations than both F₂ and M₂ populations. The number of potential genotypes varied considerably across the traits and the populations. The F₂M₂ (γ) population showed higher number of potential progeny lines compared to F₂, F₂M₂ (EMS) and M₂ populations. This indicated greater possibility of generation of potential genotypes through irradiation in heterozygous condition than EMS.