Bhagat, Y.S.Kamble, Kranti Pandit2023-03-202023-03-202023-02-1523261https://krishikosh.egranth.ac.in/handle/1/5810195519Soybean (Glycine max L.) is considered as one of the most nourishing food due to its high protein content which also meets requirements of all the essential amino acid to support normal growth and development of individuals. It also offers economic empowerment to the farmers due to its uses far beyond food and feed. Because of its many uses, it is known as the golden bean and the miracle crop of the 21st century. Mutations play a vital role in any crop improvement programme particularly which naturally occurring genetic variability has exhausted. The genetic variability present in any crop is of vital importance in the formulation of effective breeding programme. Ethyl Methane Sulfonate (EMS) is a mutagenic, teratogenic and possibly carcinogenic organic compound with formula C3H8O3S. It produces random mutations in genetic material by nucleotide substitution; particularly by guanine alkylation and it typically produces only point mutations. Soybean mutant lines treated with different EMS concentration exhibited significant differences for different morphological variations viz., number of primary branches, number of seeds per plant, plant height and number of pods per plant and test weight. Laboratory evaluation of M1 generation treatments viz., M1T2, M1T4 and M1T6 treatments showed significantly higher germination percentage on 21 DAT. M1T6 and M1T9 treatments showed significantly lower number radicle length on 21 DAT, while M1T10, M1T1 and M1T2 showed significantly higher plumule length. In field conditions, the treatments viz., M1T1 and M1T2 showed significantly highest germination percentage on 7 DAS as well as plant stand (%) on 30 DAS. The number of branches was significantly less in number in treatment M1T10. The treatment M1T2 shows significantly higher pods per plant. The seeds per plant and plant height showed significantly less number in M1T9 treatment. In field conditions M2 mutant lines viz., M2T1, M2T7 and M2T8 showed significantly highest germination percentage on 7 DAS, while treatments M2T1, M2T4 and M2T7 showed significantly highest plant stand (%) on 30 DAS. The number of branches was significantly less in number in treatments viz., M2T5 and M2T6. The treatment M2T10 showed significantly less number of seeds per plant. The treatments viz., M2T7 and M2T1 showed significantly higher plant height. The mutagen EMS is capable of producing both types of mutants namely viable and lethal, which is an indication of significant effect on soybean. This clearly indicated the potential of EMS to create considerable variability for further breeding programme. The soybean genotypes were genotyped with 14 SSR markers in order to reveal genetic diversity. The high polymorphic content was reported that ranged from 0.00 to 0.96. The genetic similarity coefficient between ten soybean mutant lines was ranged in between 0.130 to 0.875. Highest genetic similarity (0.857) was found between M2T4 and M2T5, whereas lowest genetic similarity (0.130) was found between M2T9 and M2T3, M2T10 and M2T3, M2T10 and M2T4, M2T10 and M2T6. Cluster analysis revealed soybean mutant lines were separated into three main clusters indicating their diversity. This study showed that the highly significant variation was observed for some of the characters as results of EMS treatments of 0.2%, 0.4% and 0.6%. This clearly indicated the potential of EMS to create considerable variability for further breeding programme. The SSR markers can provide useful tools for mutant characterization, conservation and utilization, as well as for genetic and breeding studies in soybean. Genetic variation among soybean mutants based on SSR analysis could be useful to select parents to be crossed for generating appropriate populations intended for genome mapping and breeding purposes.EnglishThesis