Gamma radiation to produce soybean mutants for better plant performance and chemical composition of seeds

The supply the constant demand for new soybean cultivar, it is necessary to select superior plants in populations of high genetic variability. To generate new plant variants which would perform satisfactorily in the field and produce seeds of better composition, gamma rays can be used. Therefore, soybean seeds from line VX04-6828 were irradiated in a Co-60 source (gamma rays) in doses: 0 (control); 50; 150 and 250 Gy, and were seeded to produce the M1 generation. Potential plants of each row were identified and evaluated for their agronomic performance. The seeds of the selected plants were sown, producing the plants of M2 generation and again selected and evaluated, including the chemical composition of their seeds. It was concluded that the use of gamma radiation increases the variability in soybean, with consequent increase in the probabilities of identification of new mutants, useful to breeding programs that aim at better agronomic performance and gains in the composition of the seeds. Better results are observed when 50 to 150 Gy is applied on soybean dry seeds.